electric shock from solar panels

[Bill Wright]

A warning to aerial installers! My son Paul removed an old aerial from
the chimney and put it down on the roof, where it happened to touch the
frame of a solar panel. When he picked it up he received a severe
electric shock and he was lucky he wasn’t thrown off the roof. Obviously
the solar installation wasn’t properly earthed. Needless to say he
warned the householder that his solar installation was faulty, which
didn’t please him at all. I suggest everyone working on roofs treats
solar panels as a lethal shock hazard until proven otherwise. The last
thing you want when working at heights is an electric shock.

In the early days of television every TV and radio aerial was assumed to
be ‘live’. Maybe we need to go back to those days and work in rubber
gloves.

It was quite serious. Paul said the shock felt like 240V 50Hz, so it's
likely the whole installation wasn't earthed. The high voltage from the
panels is DC of course, but Paul said he definitely felt the 50Hz! I
asked how many Hz he counted before he let go but he said he wasn't sure!

Of course the solar industry is full of bloody cowboys, so it's no
surprise. Some of the roof fixings they've used (that we've seen) are
terrible. There's going to be a legacy of leaking roofs in a few years.
That'll extend the payback time to infinity I should think!

Bill

[Tim Watts]

If it helps, a nearby bungalow has PV panels and I can see 2 green/yellow
earth bonding wires coming off the panel frame. Looks like 6mm2 +/-

So yours sounds like a buggered installation.

--
Tim Watts Personal Blog: http://squiddy.blog.dionic.net/

http://www.sensorly.com/ Crowd mapping of 2G/3G/4G mobile signal coverage

Reading this on the web? See:
http://wiki.diyfaq.org.uk/index.php?title=Usenet

[harryagain]

"Bill Wright" <bi...@invalid.com> wrote in message
news:kr1bs4$me6$2...@speranza.aioe.org...

Not quite as simple as that. It is a controversial topic.
Bit here on the subject.
http://www.energymatters.com.au/renewable-energy/solar-power/earthing-solar-panel-frames.php


There's no reason why a roof should leak if the job is done properly.

[Brian Gaff]

I blame the squirrels myself, always eating away outdoor wires, can't see
what they see in them.
Brian

--
From the Sofa of Brian Gaff Reply address is active
"Tim Watts" <tw+u...@dionic.net> wrote in message
news:k1pdaa-...@squidward.local.dionic.net...

[Bill Wright]

harryagain wrote:

> There's no reason why a roof should leak if the job is done properly.

Well, any penetration of a roof is likely to fail eventually. But I did
mention my suspicion that the job hadn't been done to the highest standards.

I think the problem with solar panels is that there is a large number of
small holes made, so the chance of failure on a whole installation is high.

Without doubt a 'clean' roof with no attachments or penetrations is
likely to prove the most reliable, and cheapest to fix if there is a
problem.

Bill

[dennis@home]

On 03/07/2013 19:38, Bill Wright wrote:
> harryagain wrote:
>
>> There's no reason why a roof should leak if the job is done properly.
>
> Well, any penetration of a roof is likely to fail eventually. But I did
> mention my suspicion that the job hadn't been done to the highest
> standards.
>
> I think the problem with solar panels is that there is a large number of
> small holes made, so the chance of failure on a whole installation is high.
>

There shouldn't be any new holes.
The idea is too remove a tile/slate and fit a hanger bracket.
The tile/slate is then refitted without any new holes.
Repeat as required.

The rails fix to the brackets and the panels to the rails.

[Bill Wright]

You can't 'remove' individual tiles (and even more so slates) if the
roof has been properly nailed. A good slate roof is as tight as my
brother-in-law. No, sorry, I'm exaggerating. But it really is tight.
Believe me, I've been trying to find ways to route cables through roofs
for the last 40 years. If you start lifting individual tiles and slates
(even if you can, which on a well-nailed roof you won't be able to)
you'll never get the roof back to as good as it was before.
What happens if you try to force the issue with a nailed roof? Well you
will break a lot of tiles or slates.
If you do manage to slide a hanger bracket under a tile you won't be
able to nail it, and it's no good saying you'll go in the loft to do it
because of the roofing felt. So the only thing stabilising the hanger is
the weight of the tile. Wind gets under tiles and lifts them, and I've
no doubt it will get under solar panels. Constant movement is the enemy
of a sound roof.
On roofs with a gentle pitch there's always the danger of rain blowing
up under the slates, or getting sucked though due to pressure
differentials. Seen this many a time. Even a slim hanger bracket will
make this much more likely.
I've seen a lot of solar installations fixed by drilling holes through
the slates above the rafters and inserting a long bolt-thing with a
screw tip. Waterproofing is by a tight-fitting rubber grommet. It's
obvious that this arrangement is going to fail long before the panels
are worn out.
When you stand on the ground and look up at panels they look OK. But
climb up there and get hold of them and you'll often find they're quite
loose, and can be lifted up with ease, bringing tiles with them.
The solar panel job, like the aerial job, is difficult for the customer
to have a close look at, so bad work is rife.

It will end in tears believe me. Give it a few years and the shit will
hit the fan.

Bill

[John Rumm]

On 03/07/2013 20:42, Bill Wright wrote:

> You can't 'remove' individual tiles (and even more so slates) if the
> roof has been properly nailed. A good slate roof is as tight as my
> brother-in-law. No, sorry, I'm exaggerating. But it really is tight.

With a proper slated roof, then you can use a tool called a "slater's
rip" to cut through the nails in one slate and free it such that it can
be slid out. You then need to use a repair bracket (or lead strip) to
refix it since you can't get the nails back in once its in place.


--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

[Cash]

John Rumm wrote:
> On 03/07/2013 20:42, Bill Wright wrote:
>
>> You can't 'remove' individual tiles (and even more so slates) if the
>> roof has been properly nailed. A good slate roof is as tight as my
>> brother-in-law. No, sorry, I'm exaggerating. But it really is tight.
>
> With a proper slated roof, then you can use a tool called a "slater's
> rip" to cut through the nails in one slate and free it such that it
> can be slid out. You then need to use a repair bracket (or lead
> strip) to refix it since you can't get the nails back in once its in
> place.

Hello John,

To add if you don't mind?

On a properly constructed tiled roof, only 1 in 5 courses of tiles are
actually nailed (there are a few exceptions to this though which allows
those 'loose' tiles to be pushed back - and just having spent around £4500
for a new roof, I can confirm that this is still the practice (and is no
different to my time working on the bloody things).

Before you ask, I'm too bloody unfit now to clean the 'winders' of a ladder,
let alone fit a new roof myself - age is a bloody good excuse to let others
do it without being nagged by SWMBO about the cost. A very big grin here.

All the best

Cash

[dennis@home]

On 03/07/2013 20:42, Bill Wright wrote:

Sorry but you don't appear to understand roof construction or working
methods.

I have just had some of the tiles removed and a mains pressure cylinder
dropped in and its pretty easy to remove tiles as they aren't nailed
every row.

Roofers frequently remove and repair slates too, using a slate ripper.

[Arfa Daily]

"Bill Wright" <bi...@invalid.com> wrote in message

news:kr1uqo$e6r$1...@speranza.aioe.org...

Are you listening, Harry ?

Arfa

[Arfa Daily]

"Chris Hogg" <m...@privacy.net> wrote in message
news:enl8t8hs5blouuf9o...@4ax.com...

> Harks back to the thread a couple of weeks ago about the fire crew who
> weren't allowed to tackle a fire in a building that had SPs on the
> roof. In view of the above, you can see why.
>
>
> Chris
>

Ah, yes. I've been meaning to get back to the group on this one. A friend of
mine is a retained fire fighter, and he has just qualified as a crew manager
(that used to be a leading hand, I think). Anyway, I asked him what the
policy was regarding a fire in a house with solar panels on the roof. He
says that as the crew manager, it is his responsibility to ensure the safety
of his crew, and the first thing that he has to do on arrival at the scene,
is to carry out a risk assessment. Part of that is to ensure that the power
to the premises is off. This, he says, is usually as a result of killing the
main input fuse to the house, and this is normally to be found either in the
hallway or garage of domestic premises.

In the case of there being solar panels on the roof, he says that there will
be a bloody great inverter in the system somewhere, and this is often
located in the roofspace where you can't see it or get at it. He accepts
that there are safety systems in place which should result in the inverter
being killed if the mains goes out (or is taken out), but he says that
because you can't immediately get at the inverter to check that it is dead,
it has to be assumed that the protection systems could be faulty or
compromised as a result of the fire, which could mean that the inverter is
actually still operating and back-feeding the house. As a result of this,
the current advice is not to go in without the direction and approval of a
senior officer who can make the assessment that it is safe for the crews to
start spraying water around.

So there we have it. This was as of a few weeks ago, and the situation might
be fluid and have changed again by now, or I suppose that it may vary
between brigades, but that is certainly the reason that the house that
started the discussion, burnt down ...

Arfa

[Bill Wright]

John Rumm wrote:
> On 03/07/2013 20:42, Bill Wright wrote:
>
>> You can't 'remove' individual tiles (and even more so slates) if the
>> roof has been properly nailed. A good slate roof is as tight as my
>> brother-in-law. No, sorry, I'm exaggerating. But it really is tight.
>
> With a proper slated roof, then you can use a tool called a "slater's
> rip" to cut through the nails in one slate and free it such that it can
> be slid out. You then need to use a repair bracket (or lead strip) to
> refix it since you can't get the nails back in once its in place.

Yes I've seen it done. It leaves the slate loose. It definitely reduces
the integrity of the roof.

Bill

[Bill Wright]

dennis@home wrote:

> I have just had some of the tiles removed and a mains pressure cylinder
> dropped in and its pretty easy to remove tiles as they aren't nailed
> every row.

It's putting them back that's the problem, not removing them. And they
are often nailed every row.
Fact is, if you mess about like that with a roof on the grand scale
needed by solar panels damage will be done; the roof will not be as good
as it was before.

Bill

[John Rumm]

On 03/07/2013 22:12, Cash wrote:
> John Rumm wrote:
>> On 03/07/2013 20:42, Bill Wright wrote:
>>
>>> You can't 'remove' individual tiles (and even more so slates) if the
>>> roof has been properly nailed. A good slate roof is as tight as my
>>> brother-in-law. No, sorry, I'm exaggerating. But it really is tight.
>>
>> With a proper slated roof, then you can use a tool called a "slater's
>> rip" to cut through the nails in one slate and free it such that it
>> can be slid out. You then need to use a repair bracket (or lead
>> strip) to refix it since you can't get the nails back in once its in
>> place.
>
> Hello John,
>
> To add if you don't mind?

Not at all ;-)

> On a properly constructed tiled roof, only 1 in 5 courses of tiles are
> actually nailed (there are a few exceptions to this though which allows
> those 'loose' tiles to be pushed back - and just having spent around £4500
> for a new roof, I can confirm that this is still the practice (and is no
> different to my time working on the bloody things).

Yup... I think the only time they usually do more is in very windy or
exposed locations, where they might nail every other course.

[Bill Wright]

John Rumm wrote:

>> On a properly constructed tiled roof, only 1 in 5 courses of tiles are
>> actually nailed (there are a few exceptions to this though which allows
>> those 'loose' tiles to be pushed back - and just having spent around
>> £4500
>> for a new roof, I can confirm that this is still the practice (and is no
>> different to my time working on the bloody things).
>
> Yup... I think the only time they usually do more is in very windy or
> exposed locations, where they might nail every other course.

It doesn't make any difference. A well constructed roof will be too
tight for it to be possible to lift slates without doing damage. Slates
are fragile and if you start prising them up they will break. I guess
there are a lot of broken slates now in the UK, with the break hidden
from the owner by being pushed up under the next row. You just can't
mess about with slate roofs like that without spoiling them.

Bill

[Bill Wright]

John Rumm wrote:

>> On a properly constructed tiled roof, only 1 in 5 courses of tiles are
>> actually nailed (there are a few exceptions to this though which allows
>> those 'loose' tiles to be pushed back - and just having spent around
>> £4500
>> for a new roof, I can confirm that this is still the practice (and is no
>> different to my time working on the bloody things).
>
> Yup... I think the only time they usually do more is in very windy or
> exposed locations, where they might nail every other course.

[harryagain]

"Bill Wright" <bi...@invalid.com> wrote in message

news:kr1uqo$e6r$1...@speranza.aioe.org...

You are exactly right Bill.
I have a (fake) slate roof and had that experience.
(My installation was an early days one)

Slates have to be removed with a ripper, the brackets fitted and lead
flashing put on.

There is at least one other person here has holes drilled.
This was done initially on mine but I was very suspicious & checked next
time we had heavy rain.
There were several slight drips you might easily miss. It could only get
worse and any leak can cause rot.

So Imade them come back and remove the lot and fix properly.

However the brackest they use on interlocking tiles are pretty well
foolproof,
I don't see there being a problem with those.

[Jim K]

Nah he's just denying again

Jim K

[harryagain]

"Arfa Daily" <arfa....@ntlworld.com> wrote in message
news:1Q3Bt.84$4k2...@fx31.am4...

Arfa, The facts are these.
The Pv panels produce electricity when the sun shines on them.
This can only be stopped by covering them up. (Not very practical)

If the mains power goes off for any reason the inverter shuts down/isolates
it'self
The PV is still active. And all the DC wires to the inverter. Up to
1000volts depending on how many panels, the inverter voltage and how it's
wired

[Nightjar]

On 04/07/2013 04:15, Bill Wright wrote:
> John Rumm wrote:
>
>>> On a properly constructed tiled roof, only 1 in 5 courses of tiles are
>>> actually nailed (there are a few exceptions to this though which allows
>>> those 'loose' tiles to be pushed back - and just having spent around
>>> £4500
>>> for a new roof, I can confirm that this is still the practice (and is no
>>> different to my time working on the bloody things).
>>
>> Yup... I think the only time they usually do more is in very windy or
>> exposed locations, where they might nail every other course.
>
> It doesn't make any difference. A well constructed roof will be too
> tight for it to be possible to lift slates without doing damage. Slates
> are fragile and if you start prising them up they will break.

I have found it to be a surprisingly strong material, but then I have
only ever used best Welsh slate.

> I guess
> there are a lot of broken slates now in the UK, with the break hidden
> from the owner by being pushed up under the next row. You just can't
> mess about with slate roofs like that without spoiling them.

You can, if you know what you are doing and have the right tools
although, as John says, you cannot re-nail a slate that you have removed
and replaced, but have to use a slate hanger to fix it in place.

Colin Bignell

[Nightjar]

On 04/07/2013 07:37, harryagain wrote:
...

> Arfa, The facts are these.
> The Pv panels produce electricity when the sun shines on them.
> This can only be stopped by covering them up. (Not very practical)
>
> If the mains power goes off for any reason the inverter shuts down/isolates

> it'self...

What you mean is it should shut down, assuming it is not faulty and has
not been damaged by the fire. The Fire Brigade cannot assume that and
have to work on the principle that the house may still have live mains
inside.

Colin Bignell

[Steve Firth]

They also have to assume that even if the system is shut down that there
will be lethal voltage at roof level.

--
<•DarWin><|
_/ _/

[Tim Watts]

Non slates shouldn't be nailed every row. My roofers (who proved they knew
what they were doing) opted for every 4th row. That does depend on the tile
type and roof slope. You'd love my roof - the reccomended way to walk up it
is to slide up a tile (interlocking) on every 3rd row (missing the nailed
rows) and expose the 2x1 batten and step on that. I tried it under their
direction and it works!

[charles]

In article <51d4a9e9$0$1199$c3e8da3$fdf4...@news.astraweb.com>,

There is a difference between titles and slates. Slates are flat and need
to be nailed in while tiles, generally, have 'nibs' which support the tile
on the battens. They only need the occasional nail.

--
From KT24

Using a RISC OS computer running v5.18

[John Williamson]

When I had the slate roof on my then home re-timbered, the roofer not
only re-used over 90% of the slates, he renailed them. He also put all
the new slates on the back, so the front view was identical to the way
it was before.

When I looked on Streetview recently, the roof still looked perfect.

If you remove a single slate,then they are impossible to re-nail,
though. My roof had a dozen or more hangers showing before I looked at
the woodwork.
--
Tciao for Now!

John.

[Mike Clarke]

Arfa Daily wrote:

> Ah, yes. I've been meaning to get back to the group on this one. A friend
> of mine is a retained fire fighter, and he has just qualified as a crew
> manager (that used to be a leading hand, I think). Anyway, I asked him
> what the policy was regarding a fire in a house with solar panels on the
> roof. He says that as the crew manager, it is his responsibility to ensure
> the safety of his crew, and the first thing that he has to do on arrival
> at the scene, is to carry out a risk assessment. Part of that is to ensure
> that the power to the premises is off. This, he says, is usually as a
> result of killing the main input fuse to the house, and this is normally
> to be found either in the hallway or garage of domestic premises.

Now that's making me wonder what would be the situation with our bungalow.
We don't have solar panels but the meter and CU are in the eaves space
because the supply was originally via overhead cables. At some time in the
distant past it was changed to an underground supply with a cable running up
the outside of the house into the roof. There's no way a firefighter could
get to this without going right through the burning house, assuming that he
even knew where it was. The thick cable running up the wall would give a
clue but for most of the year it's well hidden behind the dense foliage of a
wisteria which grows up the wall.

--
Mike Clarke

[Dave Liquorice]

On Thu, 04 Jul 2013 08:24:28 +0100, Nightjar wrote:

>>>> On a properly constructed tiled roof, only 1 in 5 courses of
tiles

>>>> are actually nailed ...

>>>
>>> Yup... I think the only time they usually do more is in very
windy or
>>> exposed locations, where they might nail every other course.
>>
>> It doesn't make any difference. A well constructed roof will be
too
>> tight for it to be possible to lift slates without doing damage.
Slates
>> are fragile and if you start prising them up they will break.

Nice shift there from tiles to slates. B-)

Unnailed tiles will push up enough across a course or two to gain
access to the laths to hook/fix the brackets that then stick out
below the bottom edge of the tiles for the panels.

>> I guess there are a lot of broken slates now in the UK, with the
break
>> hidden from the owner by being pushed up under the next row. You
just
>> can't mess about with slate roofs like that without spoiling them.
>
> You can, if you know what you are doing and have the right tools
> although, as John says, you cannot re-nail a slate that you have removed
> and replaced, but have to use a slate hanger to fix it in place.

Even properly removed with the use for ripper and decent clips(*) the
removed slate is still not as firm as it was before being buggered
about with it.

The slidey up brackety things don't work well on slates as you can't
get at the laths well enough to get a decent fixing for the bracket.
The only lath you can get at all is only accessable in the gap
between slates. So you can't hook the bracket onto the lath or get
more than a single screw/nail in.

Drilling into rafters and dowel screws with "nutted down" sealing
gromits is not a nice solution but is pretty much the only one.
Otherwise you are into lifting a lot of slates, cutting around the
bracket, putting in flashing around the bracket, sealing flashing to
bracket or having some other good overlap cover from exposed bracket
over the flashing. The slates that have been removed to get access
won't be as well fixed as they where and so on...

(*) Lead or copper strips are traditional but aren't very good, wire
clips probably not much better as they work in the same way. I use
the plastic
ones:

http://www.roofinglines.co.uk/_sysFiles/content/inventory/products/zoo
m/UBBINK-SIM-FIX-Slate-Strap-Pack-of-50-2.jpg

http://tinyurl.com/nov2p34

The lower T section is slid up the gap between the two underneath
slates and the strap is nailed to the middle lath between them. The
the loose slate pushed up under the upper two slates and the top edge
onto the upper lath (that's the hard bit) to the correct position and
the T/slopey bit pushed up the strap to hold it in place. The slidey
bit is on a ratchet so it doesn't slide back down.

--
Cheers
Dave.

[Dave Liquorice]

On Thu, 04 Jul 2013 02:17:08 +0100, Bill Wright wrote:

> It's putting them back that's the problem, not removing them. And they
> are often nailed every row. Fact is, if you mess about like that with a
> roof on the grand scale needed by solar panels damage will be done; the
> roof will not be as good as it was before.

And the installers probably won't religiously work from roof ladders
but walk about on the slates or tiles which will crack or break them.
Cracked ones won't show until they break (frost action) after a
while...

--
Cheers
Dave.

[tony sayer]

>> So there we have it. This was as of a few weeks ago, and the situation
>> might be fluid and have changed again by now, or I suppose that it may
>> vary between brigades, but that is certainly the reason that the house
>> that started the discussion, burnt down ...
>>
>> Arfa
>
>
>Arfa, The facts are these.
>The Pv panels produce electricity when the sun shines on them.
>This can only be stopped by covering them up. (Not very practical)
>


>If the mains power goes off for any reason the inverter shuts down/isolates
>it'self
>The PV is still active. And all the DC wires to the inverter. Up to
>1000volts depending on how many panels, the inverter voltage and how it's
>wired
>
>

Harry that assumption is rather shall.. we say suspect?. So here we have
a possible potential of several hundred volts DC which may, or may not
be connected to anything or everything.

That potential and where it rises and what its across is unlike the
mains incomer it's a very suspect power source. We can only assume that
its going to behave the way it should. The problem is that the power
source is up there on the roof with cables coming down into the building
and even if the inverter does shut down or go tits up whatever, there is
still that power "source" up there and thats the real problem. In a fire
situation theres no way of knowing where it is or what its doing or
where its connected to or to what its connected either.

It may well be safe it may well do what its supposed to do but its
analogous to having say large structures all over the roof and a cable
coming from next door and connected to that wherever you wish and under
fire conditions what has melted thru, what has accidentally connected to
whatever?...

The more you think about it the more awkward this one gets for the
safety of anyone up there on the roof, or squirting water up there.

Perhaps we shall see apparatus like what they use on high voltage power
line working where they bond the cables together and put a big earthing
stake in!..


--
Tony Sayer

[tony sayer]

In article <51d4a9e9$0$1199$c3e8da3$fdf4...@news.astraweb.com>,
dennis@home <den...@killspam.kicks-ass.net> scribeth thus

>On 03/07/2013 20:42, Bill Wright wrote:
>Sorry but you don't appear to understand roof construction or working
>methods.
>

Dennis .. I rather think that over his time as an aerial rigger Bill has
spent more time and been on more roofs that you've even seen!....

--
Tony Sayer

[Nightjar]

AIUI, the main concern is cables inside the house that may be exposed by
the fire and that fire fighters may come into contact with if they enter
the building.

Colin Bignell

[Dave Liquorice]

On Thu, 4 Jul 2013 02:01:47 +0100, Arfa Daily wrote:

> Anyway, I asked him what the policy was regarding a fire in a house with
> solar panels on the roof. He says that as the crew manager, it is his
> responsibility to ensure the safety of his crew, and the first thing
> that he has to do on arrival at the scene, is to carry out a risk
> assessment. Part of that is to ensure that the power to the premises is
> off. This, he says, is usually as a result of killing the main input
> fuse to the house, and this is normally to be found either in the
> hallway or garage of domestic premises.

Hum, in our case there are several CU's dotted about the place, or do
you really mean that they find and pull the main cut out? The
location of that is not immedately obvious here but could probably be
worked out by where the overhead feed runs.

The local ambulance service have a database of actual location and
directions to homes so they can find them quickly. In rural areas the
post code isn't good enough and the caller may not know it... The
information being provided by the home owners. I wonder if the fire
service also have such a database, location of the property(*) and
location/access to things like mains cut outs?

> In the case of there being solar panels on the roof, he says that there
> will be a bloody great inverter in the system somewhere, and this is
> often located in the roofspace where you can't see it or get at it. He
> accepts that there are safety systems in place which should result in
> the inverter being killed if the mains goes out (or is taken out), but
> he says that because you can't immediately get at the inverter to check
> that it is dead, it has to be assumed that the protection systems could
> be faulty or compromised as a result of the fire, which could mean that
> the inverter is actually still operating and back-feeding the house. As
> a result of this, the current advice is not to go in without the
> direction and approval of a senior officer who can make the assessment
> that it is safe for the crews to start spraying water around.

Seems wise, as far as entry in concerned. But it doesn't stop 'em
standing back, breaking windows and squirting loads of water in,
won't stop the fire but may contain it.

I wonder what the insurance companies are making of this?

> ... I suppose that it may vary between brigades, ...

And possibly where you live. Fire cover here is a single pump with
retained crew, they can probably get to most most homes around here
in 10 to 15 minutes from the brigade receiving the call. If the place
has solar PV and they don't enter until a senior officer has arrived
(at least 30 to 40 mins) and given the OK, the place will be
effectively burnt down.

Having said that in 10-15 minuets the place will be well alight
anyway as a couple did more or less burn down in the last few years
and that was without solar PV slowing down entry.

(*) The fire service will most likely have a bit of a give away from
the great column of smoke from the fire, the ambulance may well not
have that.

--
Cheers
Dave.

[Thomas Prufer]

On Thu, 04 Jul 2013 08:31:07 +0100, Nightjar <c...@insert.my.surname.here.me.uk>
wrote:

>What you mean is it should shut down, assuming it is not faulty and has
>not been damaged by the fire. The Fire Brigade cannot assume that and
>have to work on the principle that the house may still have live mains
>inside.

AFAIK, here, the minimum distance for a spray (not stream) of water to be safely
directed at an electrical installation carrying up to 1000 Volts is one meter.
So I think live mains is not much of a problem, as far as spraying water goes.

Compare that to the dangers of a electric hybrid vehicle in the garage, with a
battery storing a significant amount of energy, using lithium which can do odd
things in a fire with water added. Or propane/butane tanks, properly or
improperly stored, the nasty by-products of burning PVC, a full cistern sitting
on rafters that are burning, and PV panels are just one more thing in a long
list of caveats.


Thomas Prufer

[Arfa Daily]

"Mike Clarke" <uceb...@milibyte.co.uk> wrote in message
news:1372930154...@milibyte.co.uk...

I will see my fire fighter chum tomorrow, Mike. If I remember, I'll ask him
for you ...

Arfa

[dochol...@gmail.com]

There must be many houses like mine (most of the ones in my street, for example) where the electricity supply comes in from an underground cable directly into the cellar. To get to it you have to go down stairs at the back of the main part of the house, then from the bottom of the stairs all the way to the far corner of the cellar. Gas comes in there, too...
House next door had a fire some years back, and the fire brigade got it under control quite quickly, so they must have some procedure worked out.

[RobertL]

On Thursday, 4 July 2013 02:01:47 UTC+1, Arfa Daily wrote:
> >
> So there we have it. This was as of a few weeks ago, and the situation might
> be fluid and have changed again by now, or I suppose that it may vary
> between brigades, but that is certainly the reason that the house that
> started the discussion, burnt down ...

So presumably we will in due course see fire insurance premiums 9for houses with PV) rise as a result.

Robert

[RobertL]

and difficulty in obtaining a mortgage...
http://toryaardvark.com/2012/04/12/solar-panels-are-a-killer-for-mortgages-part-2/

Robert

[Bill Taylor]

That applies to rent-a-roof schemes where the home owner doesn't own
the panels.

[news]

On 04/07/2013 12:08, dochol...@gmail.com wrote:

> There must be many houses like mine (most of the ones in my street, for example)
> where the electricity supply comes in from an underground cable
directly into the cellar.
> To get to it you have to go down stairs at the back of the main part of the house,
> then from the bottom of the stairs all the way to the far corner of
the cellar.
> Gas comes in there, too...
> House next door had a fire some years back, and the fire brigade got it under control
> quite quickly, so they must have some procedure worked out.
>

You say "some years back" - might that have been before the days of
needing a risk assessment to even put their wellies on?


--
Chris

[Nightjar]

On 04/07/2013 10:40, Thomas Prufer wrote:
> On Thu, 04 Jul 2013 08:31:07 +0100, Nightjar <c...@insert.my.surname.here.me.uk>
> wrote:
>
>> What you mean is it should shut down, assuming it is not faulty and has
>> not been damaged by the fire. The Fire Brigade cannot assume that and
>> have to work on the principle that the house may still have live mains
>> inside.
>
> AFAIK, here, the minimum distance for a spray (not stream) of water to be safely
> directed at an electrical installation carrying up to 1000 Volts is one meter.

> So I think live mains is not much of a problem, as far as spraying water goes....

As I said in another reply, AIUI, the problem is firemen inside the
building walking into exposed live cables, or breaking into them when
cutting into walls or ceilings when trying to reach the seat of a fire.

Colin Bignell

[harryagain]

"Nightjar" <c...@insert.my.surname.here.me.uk> wrote in message
news:IfOdna9spbJcuUjM...@giganews.com...

The inverter can't work without mains power any more than an electric motor
can.

There are AC and DC isolators adjacent to the inverter

But the DC is always there on the panels in sunlight.

[harryagain]

"tony sayer" <to...@bancom.co.uk> wrote in message
news:Ui3W2u$wQT1...@bancom.co.uk...

Well that wouldn't work, HV is de-energised before it is earthed before
working on.

The point is that you can't stop the panels from functioning in daylight
(other than covering them up.)_

Maybe they could have a spray paint device.

[dennis@home]

If you read it then you can see its a load of B$.

Just how can the new owners be landed with a bill to buyout the panels
when they can't buy the house to be the new owners?

It says they didn't give an outright yes but wanted to see the contract
on the panels. Yet the article claims they can't get a mortgage. How
does he know if he doesn't actually try?

[dennis@home]

I am friends with a building inspector who is a chartered structural
engineer and has been doing buildings for decades.
I will believe what he tells me.
Why do you think I let someone put a hole in my roof big enough to put a
water cylinder through, if he had said it was likely to be a problem it
wouldn't have happened.
You can't even see where it was done from the outside and its only the
new sarking that gives it away inside.

[The Medway Handyman]

On 04/07/2013 10:08, Dave Liquorice wrote:
> On Thu, 4 Jul 2013 02:01:47 +0100, Arfa Daily wrote:
>
>> Anyway, I asked him what the policy was regarding a fire in a house with
>> solar panels on the roof. He says that as the crew manager, it is his
>> responsibility to ensure the safety of his crew, and the first thing
>> that he has to do on arrival at the scene, is to carry out a risk
>> assessment. Part of that is to ensure that the power to the premises is
>> off. This, he says, is usually as a result of killing the main input
>> fuse to the house, and this is normally to be found either in the
>> hallway or garage of domestic premises.
>
> Hum, in our case there are several CU's dotted about the place, or do
> you really mean that they find and pull the main cut out? The
> location of that is not immedately obvious here but could probably be
> worked out by where the overhead feed runs.
>
> The local ambulance service have a database of actual location and
> directions to homes so they can find them quickly. In rural areas the
> post code isn't good enough and the caller may not know it... The
> information being provided by the home owners. I wonder if the fire
> service also have such a database, location of the property(*) and
> location/access to things like mains cut outs?

London Ambulance use a system called FREDA (Fast Response Electronic
Dispatch of Ambulances). As soon as control has the address, the info
is sent to a data terminal in the ambulance, the system sets the
ambulance's sat nav - and its position is fed back to control.

Very often the crew get the address before they get the details of the
job. They also get updated by control on the way.

The system has a database of historic incidents by postcode, so in some
areas the data terminal will flash up 'stab vest mandatory' or 'do not
leave ambulance until Police are on scene'.

On Cat A calls, control stay on the phone to the caller, they can tell
them where the ambo is and when the ambo gets to the street, control
tell to caller to send someone outside to wave (if possible).



--
Dave - The Medway Handyman www.medwayhandyman.co.uk

[Tim Watts]

On Thursday 04 July 2013 19:17 The Medway Handyman wrote in uk.d-i-y:


> The system has a database of historic incidents by postcode, so in some
> areas the data terminal will flash up 'stab vest mandatory' or 'do not
> leave ambulance until Police are on scene'.

Christ, it's a shit world...

> On Cat A calls, control stay on the phone to the caller, they can tell
> them where the ambo is and when the ambo gets to the street, control
> tell to caller to send someone outside to wave (if possible).
>
>
>
--

[Cash]

Bill Wright wrote:

> John Rumm wrote:
>
>>> On a properly constructed tiled roof, only 1 in 5 courses of tiles

>>> are actually nailed (there are a few exceptions to this though
>>> which allows those 'loose' tiles to be pushed back - and just
>>> having spent around £4500
>>> for a new roof, I can confirm that this is still the practice (and
>>> is no different to my time working on the bloody things).

>>
>> Yup... I think the only time they usually do more is in very windy or
>> exposed locations, where they might nail every other course.
>
> It doesn't make any difference. A well constructed roof will be too
> tight for it to be possible to lift slates without doing damage.
> Slates are fragile and if you start prising them up they will break.

> I guess there are a lot of broken slates now in the UK, with the
> break hidden from the owner by being pushed up under the next row.
> You just can't mess about with slate roofs like that without spoiling
> them.

> Bill

With all due respects Bill, slates really are tougher than you seem to
think, and it's perfectly possible to 'lift' these without damage as they
are not fitted that "tight" (and that includes Welsh, Belgian, Asbestos
Cement and today's Asbestos-free ones) by using the proper tool for the
job - a slate ripper. The problem is actually re-nailing the last slate in a
repair below the ridge line because the nail would be covered by the slate
above it - and this is where lead or zinc 'tingles' are used at the bottom
of that slate to stop it falling. [1]

When you see slates broken the way that you describe, this is usually caused
(apart from weather) by the uninitiated/dim-witted and cowboy builders
trying to lift the slate using screwdrivers or any other odd tool that comes
to hand.

Tiles are an entirely different kettle of fish to fix.

[1] I've even seen the 'new-fangled' silicone mastic used to 'stick'
slates in place by the unscrupulous from the first time the stuff came into
general use on buildings.

Cash

[John Rumm]

On 04/07/2013 04:15, Bill Wright wrote:
> John Rumm wrote:
>
>>> On a properly constructed tiled roof, only 1 in 5 courses of tiles are
>>> actually nailed (there are a few exceptions to this though which allows
>>> those 'loose' tiles to be pushed back - and just having spent around
>>> £4500
>>> for a new roof, I can confirm that this is still the practice (and is no
>>> different to my time working on the bloody things).
>>
>> Yup... I think the only time they usually do more is in very windy or
>> exposed locations, where they might nail every other course.
>
> It doesn't make any difference. A well constructed roof will be too
> tight for it to be possible to lift slates without doing damage. Slates
> are fragile and if you start prising them up they will break. I guess
> there are a lot of broken slates now in the UK, with the break hidden
> from the owner by being pushed up under the next row. You just can't
> mess about with slate roofs like that without spoiling them.

I have (fake, i.e. Eternit) slate on my roof... I would not dream of
prising one "up". But you can quite easily slide one down and out if
required (and the nails have been cut).

(I have never needed to deliberately remove one so far, but have needed
to replace a couple that broke for other reasons)


--
Cheers,

John.

/=================================================================\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\=================================================================/

[Dave Liquorice]

On Thu, 04 Jul 2013 21:44:07 +0100, Tim Watts wrote:

>> The system has a database of historic incidents by postcode, so in
some
>> areas the data terminal will flash up 'stab vest mandatory' or 'do
not
>> leave ambulance until Police are on scene'.
>
> Christ, it's a shit world...

THM's daughter works for the London Ambulance Service, London is a
shit place to live, no I'll rephrase that, a shit place to exist. So
are parts of many other big cities.

--
Cheers
Dave.

[Dave Plowman (News)]

In article <nyyfbegfubjuvyypb...@srv1.howhill.co.uk>,

Dave Liquorice <allsortsn...@howhill.com> wrote:
> THM's daughter works for the London Ambulance Service, London is a
> shit place to live, no I'll rephrase that, a shit place to exist. So
> are parts of many other big cities.

At least we get decent radio reception here. ;-)

--
*Why doesn't glue stick to the inside of the bottle?

Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.

[Bill Wright]

dennis@home wrote:

> I am friends with a building inspector

I once slept with a joiner's wife. So what?

> Why do you think I let someone put a hole in my roof big enough to put a
> water cylinder through, if he had said it was likely to be a problem it
> wouldn't have happened.

Making one large hole and then re-tiling and doing it with care is quite
different to the solar panel lads making umpteen little leakage points
all over your roof.

> You can't even see where it was done from the outside and its only the
> new sarking that gives it away inside.

It isn't the appearance that matters. This is one problem with solar; a
lot of the damage is hidden by the panels.

Bill

[Bill Wright]

harryagain wrote:

> The inverter can't work without mains power any more than an electric motor
> can.

My windscreen wipers work OK on 12V DC.

Bill

[harryagain]

"Arfa Daily" <arfa....@ntlworld.com> wrote in message
news:4B3Bt.7$XN...@fx01.am4...
>
>
> "Bill Wright" <bi...@invalid.com> wrote in message
> news:kr1uqo$e6r$1...@speranza.aioe.org...
>> dennis@home wrote:
>>> On 03/07/2013 19:38, Bill Wright wrote:
>>>> harryagain wrote:
>>>>
>>>>> There's no reason why a roof should leak if the job is done properly.
>>>>
>>>> Well, any penetration of a roof is likely to fail eventually. But I did
>>>> mention my suspicion that the job hadn't been done to the highest
>>>> standards.
>>>>
>>>> I think the problem with solar panels is that there is a large number
>>>> of
>>>> small holes made, so the chance of failure on a whole installation is
>>>> high.
>>>>
>>>
>>> There shouldn't be any new holes.
>>> The idea is too remove a tile/slate and fit a hanger bracket.
>>> The tile/slate is then refitted without any new holes.
>>> Repeat as required.
>>>
>>> The rails fix to the brackets and the panels to the rails.
>>
>> You can't 'remove' individual tiles (and even more so slates) if the roof
>> has been properly nailed. A good slate roof is as tight as my
>> brother-in-law. No, sorry, I'm exaggerating. But it really is tight.
>> Believe me, I've been trying to find ways to route cables through roofs
>> for the last 40 years. If you start lifting individual tiles and slates
>> (even if you can, which on a well-nailed roof you won't be able to)
>> you'll never get the roof back to as good as it was before.
>> What happens if you try to force the issue with a nailed roof? Well you
>> will break a lot of tiles or slates.
>> If you do manage to slide a hanger bracket under a tile you won't be able
>> to nail it, and it's no good saying you'll go in the loft to do it
>> because of the roofing felt. So the only thing stabilising the hanger is
>> the weight of the tile. Wind gets under tiles and lifts them, and I've no
>> doubt it will get under solar panels. Constant movement is the enemy of a
>> sound roof.
>> On roofs with a gentle pitch there's always the danger of rain blowing up
>> under the slates, or getting sucked though due to pressure differentials.
>> Seen this many a time. Even a slim hanger bracket will make this much
>> more likely.
>> I've seen a lot of solar installations fixed by drilling holes through
>> the slates above the rafters and inserting a long bolt-thing with a screw
>> tip. Waterproofing is by a tight-fitting rubber grommet. It's obvious
>> that this arrangement is going to fail long before the panels are worn
>> out.
>> When you stand on the ground and look up at panels they look OK. But
>> climb up there and get hold of them and you'll often find they're quite
>> loose, and can be lifted up with ease, bringing tiles with them.
>> The solar panel job, like the aerial job, is difficult for the customer
>> to have a close look at, so bad work is rife.
>>
>> It will end in tears believe me. Give it a few years and the shit will
>> hit the fan.
>>
>> Bill
>>
>
> Are you listening, Harry ?
>
> Arfa

Chimneys penetrate slate roof with no problems because the job is done
properly, ie with lead flashing or soakers
Also sewage system vent pipes using a lead slate.
All down to the work being done properly.

The problem arises with cowboy installers not doing this which obviously
takes time and money.
And you can be sure I supervised every aspect of my installation. (I got
upon the roof.)

Even if you can't get up there you can use binoculars, you need to see the
work being done before the panels are fitted which hides a lot of it.

But these problems mostly arise with (fake) slate roofs. Interlocking tiles
are far less problematic.

[harryagain]

"dennis@home" <den...@killspam.kicks-ass.net> wrote in message
news:51d5b8a3$0$1720$c3e8da3$dbd...@news.astraweb.com...

It is not BS
The contract with these "rent-a-roof" people varies.
Mostly if you sell your house, you have to buy the PV system off of them at
vary onerous terms. (ie like three times the installtion cost.) So you could
end up shelling out Ł40,000.

If you own the system, as most do, they are a big asset/selling point as
they represent tax free, inflation linked income for the next twenty odd
years.

The point is that rent-a-roof is/was a very bad idea. Dunno if these firms
are still in operation these days.

[Dave Plowman (News)]

In article <kr5oek$4tq$1...@dont-email.me>,

harryagain <harol...@aol.com> wrote:
> Chimneys penetrate slate roof with no problems because the job is done
> properly, ie with lead flashing or soakers
> Also sewage system vent pipes using a lead slate.
> All down to the work being done properly.

It's not common to add a chimney after the roof is finished.

--
*Frankly, scallop, I don't give a clam

[tony sayer]

In article <51d5bc16$0$1667$c3e8da3$5d8f...@news.astraweb.com>,

Yes you had to ask someone else. I rather think that bill has that
knowledge from experience!..
--
Tony Sayer

[tony sayer]

>>
>> The more you think about it the more awkward this one gets for the
>> safety of anyone up there on the roof, or squirting water up there.
>>
>> Perhaps we shall see apparatus like what they use on high voltage power
>> line working where they bond the cables together and put a big earthing
>> stake in!..
>
>
>Well that wouldn't work, HV is de-energised before it is earthed before
>working on.
>
>The point is that you can't stop the panels from functioning in daylight
>(other than covering them up.)_
>
>Maybe they could have a spray paint device.
>
>

Or tinfoil hats;)...
--
Tony Sayer

[tony sayer]

In article <nyyfbegfubjuvyypb...@srv1.howhill.co.uk>, Dave

Liquorice <allsortsn...@howhill.com> scribeth thus

Someone I know works for one of the professions and commutes as he needs
to get away from the grimy underbelly of what London is ..
--
Tony Sayer

[Arfa Daily]

"Mike Clarke" <uceb...@milibyte.co.uk> wrote in message
news:1372930154...@milibyte.co.uk...

> Arfa Daily wrote:
>
>> Ah, yes. I've been meaning to get back to the group on this one. A friend
>> of mine is a retained fire fighter, and he has just qualified as a crew

>> manager (that used to be a leading hand, I think). Anyway, I asked him

>> what the policy was regarding a fire in a house with solar panels on the
>> roof. He says that as the crew manager, it is his responsibility to
>> ensure
>> the safety of his crew, and the first thing that he has to do on arrival
>> at the scene, is to carry out a risk assessment. Part of that is to
>> ensure
>> that the power to the premises is off. This, he says, is usually as a
>> result of killing the main input fuse to the house, and this is normally
>> to be found either in the hallway or garage of domestic premises.
>

> Now that's making me wonder what would be the situation with our bungalow.
> We don't have solar panels but the meter and CU are in the eaves space
> because the supply was originally via overhead cables. At some time in the
> distant past it was changed to an underground supply with a cable running
> up
> the outside of the house into the roof. There's no way a firefighter could
> get to this without going right through the burning house, assuming that
> he
> even knew where it was. The thick cable running up the wall would give a
> clue but for most of the year it's well hidden behind the dense foliage of
> a
> wisteria which grows up the wall.
>

> --
> Mike Clarke
>

OK. Saw my firefighter chum today, and asked him what the situation is in a
case like yours where the location of the company fuse is not obvious. When
asked, he added to that scenario by saying that even when the location of
the CU / company fuse *is* known, it's not always possible to get to it, as
the fire might be raging away in your way. He says that in these cases, it
comes down to the judgment of the crewman doing the evaluation, and that in
most cases, he will send the guys in with a warning that the premises have
not been isolated, and this fact will be noted on the risk assessment sheet.
Apparently, what will then normally happen in these cases, is that pretty
soon after they start spraying water around, MCBs in the house will start to
pop, effectively providing an acceptable level of isolation. In the event
that these are damaged and don't pop, he says that the company fuse will
usually blow. Also, he says that it is not at all uncommon for one of the
big two-handed fuses down the road in the substation to pop, putting out
half of the street ...

So, again, it looks like there is a degree of common sense involved on the
part of the fire officers, which leaves it all a bit in the air, really ...

Arfa

[The Other Mike]

On Thu, 4 Jul 2013 09:37:04 +0100, tony sayer <to...@bancom.co.uk>
wrote:

>Perhaps we shall see apparatus like what they use on high voltage power
>line working where they bond the cables together and put a big earthing
>stake in!..

They wash insulators and switchgear live, with water, from just a few
metres away.

Not 240v stuff though. Grid system voltages and *very* pure water.

[Nightjar]

On 04/07/2013 18:31, harryagain wrote:
> "Nightjar" <c...@insert.my.surname.here.me.uk> wrote in message
> news:IfOdna9spbJcuUjM...@giganews.com...
>> On 04/07/2013 07:37, harryagain wrote:
>> ...
>>> Arfa, The facts are these.
>>> The Pv panels produce electricity when the sun shines on them.
>>> This can only be stopped by covering them up. (Not very practical)
>>>
>>> If the mains power goes off for any reason the inverter shuts
>>> down/isolates
>>> it'self...
>>
>> What you mean is it should shut down, assuming it is not faulty and has
>> not been damaged by the fire. The Fire Brigade cannot assume that and have
>> to work on the principle that the house may still have live mains inside.
>>
>> Colin Bignell
>
> The inverter can't work without mains power any more than an electric motor

> can...

I would want to see a full failure mode and effects analysis before
making such definitive statements myself.

Colin Bignell

[The Medway Handyman]

Don't know if this applies to fire hoses, but when I worked in the
pressure washer game I saw some high speed photos of a pressure jet
spray. It wasn't a single stream of water, but lots of small droplets
separate from each other.

[The Medway Handyman]

Most of Bec's crewmates live in Kent. Mainly due to house prices.

[Jonathan]

On Thursday, July 4, 2013 2:51:46 AM UTC+1, John Rumm wrote:

> On 03/07/2013 22:12, Cash wrote:
>

>
>
> Yup... I think the only time they usually do more is in very windy or
>
> exposed locations, where they might nail every other course.
>
>

We used to live in a 1950s house in a windy location. The tile roof wasn't nailed at all. When we had an extension built the builder nailed the every five rows and said the tiles were much more likely to break than on the old roof. the only risk to the old roof was that loss of a few tile could cause a catastrophic failure in high wind. We lived there for 18 years and never had a problem but you could hear the tiles lifting when it was windy. The tiles were much easier to replace if one broke.

Jonathan

[John Rumm]

On 04/07/2013 18:31, harryagain wrote:

> "Nightjar" <c...@insert.my.surname.here.me.uk> wrote in message
> news:IfOdna9spbJcuUjM...@giganews.com...
>> On 04/07/2013 07:37, harryagain wrote:
>> ...
>>> Arfa, The facts are these.
>>> The Pv panels produce electricity when the sun shines on them.
>>> This can only be stopped by covering them up. (Not very practical)
>>>
>>> If the mains power goes off for any reason the inverter shuts
>>> down/isolates
>>> it'self...
>>
>> What you mean is it should shut down, assuming it is not faulty and has
>> not been damaged by the fire. The Fire Brigade cannot assume that and have
>> to work on the principle that the house may still have live mains inside.
>>
>> Colin Bignell
>
> The inverter can't work without mains power any more than an electric motor
> can.

A motor needs mains power to actually drive it. The motive power on an
inverter is coming from the DC side. All the AC side needs to do is
provide synchronisation.

[harryagain]

"John Rumm" <see.my.s...@nowhere.null> wrote in message
news:D7qdnd6xTfQmiUrM...@brightview.co.uk...

> On 04/07/2013 18:31, harryagain wrote:
>> "Nightjar" <c...@insert.my.surname.here.me.uk> wrote in message
>> news:IfOdna9spbJcuUjM...@giganews.com...
>>> On 04/07/2013 07:37, harryagain wrote:
>>> ...
>>>> Arfa, The facts are these.
>>>> The Pv panels produce electricity when the sun shines on them.
>>>> This can only be stopped by covering them up. (Not very practical)
>>>>
>>>> If the mains power goes off for any reason the inverter shuts
>>>> down/isolates
>>>> it'self...
>>>
>>> What you mean is it should shut down, assuming it is not faulty and has
>>> not been damaged by the fire. The Fire Brigade cannot assume that and
>>> have
>>> to work on the principle that the house may still have live mains
>>> inside.
>>>
>>> Colin Bignell
>>
>> The inverter can't work without mains power any more than an electric
>> motor
>> can.
>
> A motor needs mains power to actually drive it. The motive power on an
> inverter is coming from the DC side. All the AC side needs to do is
> provide synchronisation.

The grid tie inverter is virtually anamplifier.
It gets its contol signal from the mains to generate a sine wave which is
automatically in synch.
So no mains= no signal = it can't function.
It's all part of the "anti-islanding" requirement.
But it is not considered to be isolated when self shut down

The other danger is there are capacitors on the DC side that store energy as
the mains passes through zero.
There is equipment to discharge them but it takes a few minutes.
http://en.wikipedia.org/wiki/Anti-islanding

[dennis@home]

On 05/07/2013 07:34, harryagain wrote:
> "dennis@home" <den...@killspam.kicks-ass.net> wrote in message
> news:51d5b8a3$0$1720$c3e8da3$dbd...@news.astraweb.com...
>> On 04/07/2013 12:41, RobertL wrote:
>>> On Thursday, 4 July 2013 12:38:04 UTC+1, RobertL wrote:
>>>> On Thursday, 4 July 2013 02:01:47 UTC+1, Arfa Daily wrote:
>>>>
>>>>>>
>>>>
>>>>> So there we have it. This was as of a few weeks ago, and the situation
>>>>> might
>>>>
>>>>> be fluid and have changed again by now, or I suppose that it may vary
>>>>
>>>>> between brigades, but that is certainly the reason that the house that
>>>>
>>>>> started the discussion, burnt down ...
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> So presumably we will in due course see fire insurance premiums 9for
>>>> houses with PV) rise as a result.
>>>
>>>
>>> and difficulty in obtaining a mortgage...
>>> http://toryaardvark.com/2012/04/12/solar-panels-are-a-killer-for-mortgages-part-2/
>>>
>>> Robert
>>>
>>
>> If you read it then you can see its a load of B$.
>>
>> Just how can the new owners be landed with a bill to buyout the panels
>> when they can't buy the house to be the new owners?
>>
>> It says they didn't give an outright yes but wanted to see the contract on
>> the panels. Yet the article claims they can't get a mortgage. How does he
>> know if he doesn't actually try?
>
> It is not BS

The blogg is.

> The contract with these "rent-a-roof" people varies.
> Mostly if you sell your house, you have to buy the PV system off of them at
> vary onerous terms. (ie like three times the installtion cost.) So you could
> end up shelling out Ł40,000.

The new owners don't get lumbered with a bill as the blogg claims.
They can't get a mortgage so they can't buy it in the first place.

>
> If you own the system, as most do, they are a big asset/selling point as
> they represent tax free, inflation linked income for the next twenty odd
> years.

Most don't.

>
> The point is that rent-a-roof is/was a very bad idea. Dunno if these firms
> are still in operation these days.
>

They still exist, one knocked the door a fortnight ago trying to give
them away.
>

[dennis@home]

On 05/07/2013 10:46, tony sayer wrote:

> Yes you had to ask someone else. I rather think that bill has that
> knowledge from experience!..
>

So what if its wrong?

[tony sayer]

>
>So, again, it looks like there is a degree of common sense involved on the
>part of the fire officers, which leaves it all a bit in the air, really ...
>
>Arfa
>

Interesting .. but did you ask him as to what advice, if any, they were
given in Solar panel equipped houses?...

--
Tony Sayer

[tony sayer]

In article <51d72c1c$0$1509$c3e8da3$92d0...@news.astraweb.com>,
dennis@home <den...@killspam.kicks-ass.net> scribeth thus

FFS Den he's spent year and year up on roofs prodding and poking cables
thru and around them and aerial mast's thru them etc etc...


There're not rocket science!..

--
Tony Sayer

[Vir Campestris]

On 05/07/2013 21:06, harryagain wrote:
> The grid tie inverter is virtually anamplifier.
> It gets its contol signal from the mains to generate a sine wave which is
> automatically in synch.
> So no mains= no signal = it can't function.
> It's all part of the "anti-islanding" requirement.
> But it is not considered to be isolated when self shut down
>
> The other danger is there are capacitors on the DC side that store energy as
> the mains passes through zero.
> There is equipment to discharge them but it takes a few minutes.
> http://en.wikipedia.org/wiki/Anti-islanding

Trouble is that when it's being cooked, spattered with carbon, and
having jets of dirty water all over it it isn't going to work correctly.
Can you guarantee it will never go wrong?

I might point out that never is a very very long time.

Andy

[Arfa Daily]

"tony sayer" <to...@bancom.co.uk> wrote in message
news:K9Whh2F3...@bancom.co.uk...

Yes, I detailed that further up the thread. The last advice that he had was
to await authorisation from a senior officer

Arfa

[harryagain]

"Vir Campestris" <vir.cam...@invalid.invalid> wrote in message
news:kr7gn4$npg$1...@news.albasani.net...

That applies with any electrical equipment.
But not work is almost the same as shut down.
ie fail safe.

[harryagain]

"dennis@home" <den...@killspam.kicks-ass.net> wrote in message

news:51d72bc6$0$1509$c3e8da3$92d0...@news.astraweb.com...

Don't what?

>> The point is that rent-a-roof is/was a very bad idea. Dunno if these
>> firms
>> are still in operation these days.
>>
>
> They still exist, one knocked the door a fortnight ago trying to give them
> away.

Amazing. I woldn't have thought there was enough money in it any more.
And also people would be aware of the catches with rent-a-roof.

[Chris J Dixon]

Bill Wright wrote:

>A warning to aerial installers! My son Paul removed an old aerial from
>the chimney and put it down on the roof, where it happened to touch the
>frame of a solar panel. When he picked it up he received a severe
>electric shock and he was lucky he wasn’t thrown off the roof. Obviously
>the solar installation wasn’t properly earthed. Needless to say he
>warned the householder that his solar installation was faulty, which
>didn’t please him at all. I suggest everyone working on roofs treats
>solar panels as a lethal shock hazard until proven otherwise. The last
>thing you want when working at heights is an electric shock.
>
>In the early days of television every TV and radio aerial was assumed to
>be ‘live’. Maybe we need to go back to those days and work in rubber
>gloves.
>
Have a look at page 22 (14 of the .pdf), onwards in this
document.

"Photovoltaics in Buildings Guide to the installation of PV
systems 2nd Edition"

<http://www.bre.co.uk/filelibrary/pdf/rpts/Guide_to_the_installation_of_PV_systems_2nd_Edition.pdf>

There is a decision chart which I am not going to reproduce, but
the key details for average installs are

"...it is the electrical separation of the mains from the d.c.
using an isolating transformer that is the key determining factor
when assessing the requirement for array frame earthing."

"..freestanding ground mounted, or building roof mounted arrays
(away from building metalwork) will normally not be within the
equipotential zone."

"Where the incoming supply is PME (the majority of domestic
supply arrangements), the PME earth cannot be taken outside the
equipotential zone. This is to prevent the potential shock hazard
should the supply neutral ever be lost."

" [if no isolating transformer] Install & bond to earth spike
(Note: do not take PME out of equipotential Zone) (Note: Use 10
mm2 braid or equiv) "

further, on page 39 (22 of the .pdf)

"3.3.4 Shock hazard (safe working practices)
It is important to note that, despite all the above precautions,
an installer or service engineer may still encounter an electric
shock hazard:

Always test for the presence of voltage of parts before touching
any part of the system.
Where a residual electric shock hazard is encountered, live
working practices must be adopted (see above).

An electric shock may be experienced from a capacitive discharge
– a charge may build up in the PV system due to its distributed
capacitance to ground. Such effects are more prevalent in certain
types of modules and systems, namely amorphous (thin film)
modules with metal frames or steel backing. In such
circumstances, appropriate and safe live working practices must
be adopted.

An example of where such hazards may be encountered is the case
where an installer is seated on earthed metal roof wiring a large
PV array. In such circumstances the installer must touch the PV
cabling and can get an electric shock to earth. The electric
shock voltage will increase with the number of series connected
modules. The use of insulated tools and gloves, together with
insulating matting to stand or sit on, can mitigate this hazard.

An electric shock may also be experienced due to the PV array
developing a ground leakage path. Good wiring practice, double
insulation and modules of Class II construction can significantly
reduce this problem, but in any installed systems, leakage paths
may still occur. Any person working on a PV system must be aware
of this and take the necessary precautions."

Chris
--
Chris J Dixon Nottingham UK
ch...@cdixon.me.uk

Plant amazing Acers.

[Vir Campestris]

On 06/07/2013 06:33, harryagain wrote:
> That applies with any electrical equipment.
> But not work is almost the same as shut down.
> ie fail safe.

No, it's not the same. In general electrical equipment with the mains
disconnected isn't going to give you a shock. Sure there are mains
filters but they aren'a major problem, and UPSes whic are, but are
rare. But a burning inverter will _prbably_ fail safe. But it might
stick all the DC from the panels out on the local mains circuit...

Andy

[Nightjar]

On 06/07/2013 06:33, harryagain wrote:

As I said, I would want to see the FMEA for the unit before making any
such definite statement and the fire brigade won't have that to hand.
They have to assume that it will not fail safe until proven otherwise.
Meanwhile, they can't get to the seat of the fire and your house burns down.

Colin Bignell

[dennis@home]

BTW I doubt if he is silly enough to poke wires and masts thru roofs.
He is far more likely to fix a bracket or four to the wall.

[tony sayer]

In article <51d866a9$0$2718$c3e8da3$9b4f...@news.astraweb.com>,

dennis@home <den...@killspam.kicks-ass.net> scribeth thus
>On 05/07/2013 22:28, tony sayer wrote:
>> In article <51d72c1c$0$1509$c3e8da3$92d0...@news.astraweb.com>,
>> dennis@home <den...@killspam.kicks-ass.net> scribeth thus
>>> On 05/07/2013 10:46, tony sayer wrote:
>>>
>>>> Yes you had to ask someone else. I rather think that bill has that
>>>> knowledge from experience!..
>>>>
>>>
>>> So what if its wrong?
>>
>> FFS Den he's spent year and year up on roofs prodding and poking cables
>> thru and around them and aerial mast's thru them etc etc...
>>
>>
>> There're not rocket science!..
>>
>
>So what if its wrong?
>
>
>BTW I doubt if he is silly enough to poke wires and masts thru roofs.
>He is far more likely to fix a bracket or four to the wall.

I don't think thats a silly behaviour at all if done as it should be its
fine sticking masts thru roofs as well...

http://www.wrightsaerials.co.uk/ourwork/007.shtml#img2

http://www.wrightsaerials.co.uk/ourwork/020.shtml

http://www.wrightsaerials.co.uk/ourwork/016.shtml
--
Tony Sayer

[Windmill]

"harryagain" <harol...@aol.com> writes:


>"Arfa Daily" <arfa....@ntlworld.com> wrote in message
>news:1Q3Bt.84$4k2...@fx31.am4...
>>
>>
>> "Chris Hogg" <m...@privacy.net> wrote in message
>> news:enl8t8hs5blouuf9o...@4ax.com...
>>> On Wed, 03 Jul 2013 15:18:37 +0100, Bill Wright <bi...@invalid.com>

>>> wrote:
>>>
>>>>A warning to aerial installers! My son Paul removed an old aerial from
>>>>the chimney and put it down on the roof, where it happened to touch the
>>>>frame of a solar panel. When he picked it up he received a severe
>>>>electric shock and he was lucky he wasn't thrown off the roof. Obviously
>>>>the solar installation wasn't properly earthed. Needless to say he
>>>>warned the householder that his solar installation was faulty, which
>>>>didn't please him at all. I suggest everyone working on roofs treats
>>>>solar panels as a lethal shock hazard until proven otherwise. The last
>>>>thing you want when working at heights is an electric shock.
>>>>
>>>>In the early days of television every TV and radio aerial was assumed to
>>>>be 'live'. Maybe we need to go back to those days and work in rubber
>>>>gloves.
>>>>

>>>>It was quite serious. Paul said the shock felt like 240V 50Hz, so it's
>>>>likely the whole installation wasn't earthed. The high voltage from the
>>>>panels is DC of course, but Paul said he definitely felt the 50Hz! I
>>>>asked how many Hz he counted before he let go but he said he wasn't sure!
>>>>
>>>>Of course the solar industry is full of bloody cowboys, so it's no
>>>>surprise. Some of the roof fixings they've used (that we've seen) are
>>>>terrible. There's going to be a legacy of leaking roofs in a few years.
>>>>That'll extend the payback time to infinity I should think!
>>>>
>>>>Bill
>>> Harks back to the thread a couple of weeks ago about the fire crew who
>>> weren't allowed to tackle a fire in a building that had SPs on the
>>> roof. In view of the above, you can see why.
>>>
>>>
>>> Chris

>>>
>>
>> Ah, yes. I've been meaning to get back to the group on this one. A friend
>> of mine is a retained fire fighter, and he has just qualified as a crew
>> manager (that used to be a leading hand, I think). Anyway, I asked him
>> what the policy was regarding a fire in a house with solar panels on the
>> roof. He says that as the crew manager, it is his responsibility to ensure
>> the safety of his crew, and the first thing that he has to do on arrival
>> at the scene, is to carry out a risk assessment. Part of that is to ensure
>> that the power to the premises is off. This, he says, is usually as a
>> result of killing the main input fuse to the house, and this is normally
>> to be found either in the hallway or garage of domestic premises.
>>

>> In the case of there being solar panels on the roof, he says that there
>> will be a bloody great inverter in the system somewhere, and this is often
>> located in the roofspace where you can't see it or get at it. He accepts
>> that there are safety systems in place which should result in the inverter
>> being killed if the mains goes out (or is taken out), but he says that
>> because you can't immediately get at the inverter to check that it is
>> dead, it has to be assumed that the protection systems could be faulty or
>> compromised as a result of the fire, which could mean that the inverter is
>> actually still operating and back-feeding the house. As a result of this,
>> the current advice is not to go in without the direction and approval of a
>> senior officer who can make the assessment that it is safe for the crews
>> to start spraying water around.

>>
>> So there we have it. This was as of a few weeks ago, and the situation
>> might be fluid and have changed again by now, or I suppose that it may
>> vary between brigades, but that is certainly the reason that the house
>> that started the discussion, burnt down ...
>>

>> Arfa

>Arfa, The facts are these.
>The Pv panels produce electricity when the sun shines on them.
>This can only be stopped by covering them up. (Not very practical)

Spray dark mud on them?

>If the mains power goes off for any reason the inverter shuts down/isolates
>it'self

>The PV is still active. And all the DC wires to the inverter. Up to
>1000volts depending on how many panels, the inverter voltage and how it's
>wired

Maybe they need a ground-level crowbar switch to short them out in an
emergency?


--
Windmill, Til...@NoneHome.com Use t m i l l
J.R.R. Tolkien:- @ S c o t s h o m e . c o m
All that is gold does not glister / Not all who wander are lost

[F]

On 04/07/2013 01:45 Arfa Daily wrote:

> Are you listening, Harry ?

Anyone else noticed he's morphed into 'harryagain'? Anything to do with
his previously published opinions on Muslims when he was posting as
'harry'...?

--
F

[harryagain]

"F" <news@nowhere> wrote in message
news:dPidneAMYM5oRkbM...@brightview.co.uk...

Harryagain is when I use outlook express.
I given up on google since they changed the format to a rubbish one.

And muslims need to be exterminated.
You can see what they're like throughout the ME now.
Not to mention paedophiles and bombers in this country.
An evil religion/people.