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Installing battery, transformer& charger in Hobby

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sionbach

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Jan 16, 2014, 9:05:13 AM1/16/14
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Hi everyone, been searching internet for a week or so now trying to
install a battery in a hobby 720 2002 european version. Ive also phoned
a few places but once I tell them I have a hobby the mood changes and
most becomes unhelpfull. The caravan is located on an airfield and is
connected to the mains most of the time and does not get moved offten,
maybe twice a year for a couple weeks at a time so would like the option
of using battery power at night when I cant fire up the generator. My
problem is, the electric goes off sometimes here so everything goes off,
lights, fan etc. I have bought a 100amp leisure battery and have
connected this to the 12v circut (after disconnecting the 240V!) but
everything runs slow. The fan for the air blown trumating heater runs
fery sluggish and the 12v lighhting is quite dim. Ive also installed a
car stereo and it does not work using the standard 12v transformer that
is in the hobby at the moment as Ive found out its only pumping out AC
and a car stereo needs DC. Ive got various 12v car phone chargers etc so
I would prefere to go DC anyway as Ive been told 12v phone chargers does
not like 12v AC electric.
I need the battery to get charged when connected to the 240v mains but
do not know wich way to go. I can buy a new transformer/ charger and
dissconect the 12v AC transformer that is currently installed or I can
buy a 12v charger only and dissconect the 12v AC tranformer. Which way
do I go? If I get the charger eg (eBay: 181299565597) I will be using
the battery all the time and this probably will unnecessary detirorate
the battery over time, or if I buy a transforme/charger (eBay:-
161147359709) that will only use the battery when there is no 240v
available, do I need to get some switches or extra things to get it to
automatically switch over. So the 2 questions I have is (1) what can I
do to get the fan and lights to work as they do on the 12v AC, The
aiblown fan is my real concern (maybee another fan motor?) as I can
change the lighting to LED & (2) should I buy a charger only or a
charger/transformer. Ive never posted on any forums before so please
accept my apologies if Ive done something wrong, posted in the wrong
place or something. I have searched various forums for this answer and
canot find an answer. Thanks for reading and any advice would be
appriciated.
The transformer that is currently installed has a german lable stating
"Wittlich 22388/98" and the output says "Sec 5-0-13.5v (10-12-15) 9.3A

This is not that important:--
Ive also got a 12v led tv that works on a 240v adapter with output 12v
4amps DC. Can I use this directly on the battery? or while
charging/transformer. I think I know the answer for this and it is a NO
as its not regulated to 12v so the only option is a 80w inverter and
still use the 240v adapter? correct? many thanks all




--
sionbach

David

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Jan 16, 2014, 3:06:36 PM1/16/14
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Hi
Have you placed the battery in the battery compartment and connected it?

I think it may well not be giving sufficient voltage out because you have
discharged it by removing the 240 v hook up so not allowing the 240v to 12 v
unit charge it.

Also when running 12v equipment when on hook up it is usually a requirement
to have a battery in place.

I do not know Hobby caravans but I never had a caravan that did not have
full 240v and 12 v.

Regards
David





"sionbach" wrote in message news:sionbach...@caravanbanter.co.uk...

Woody

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Jan 16, 2014, 3:42:21 PM1/16/14
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"David" <dnp...@tesco.net> wrote in message
news:lb9e4c$26r$1...@dont-email.me...
> Hi
> Have you placed the battery in the battery compartment and
> connected it?
>
> I think it may well not be giving sufficient voltage out
> because you have discharged it by removing the 240 v hook
> up so not allowing the 240v to 12 v unit charge it.
>
> Also when running 12v equipment when on hook up it is
> usually a requirement to have a battery in place.
>
> I do not know Hobby caravans but I never had a caravan
> that did not have full 240v and 12 v.
>

Does it not occur to you David that the OP is perhaps a
little dangerous - connecting 12V AC(!!!) to a battery?

It was also stated that this is a European Hobby: many
continental-spec vans do not come fitted with
mains/gas/cooking/hot water as we are used to here - this
may be one of them especially given its age.


--
Woody

harrogate three at ntlworld dot com


Gerard

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Jan 16, 2014, 4:21:23 PM1/16/14
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"sionbach" <sionbach...@caravanbanter.co.uk> schreef in bericht
news:sionbach...@caravanbanter.co.uk...
>
> Hi everyone, been searching internet for a week or so now trying to
> install a battery in a hobby 720 2002 european version.

I have a Dethleffs European version, because I am Dutch.

I am an electrician by trade and you are clearly not.
It's best to leave the systems in the caravan as they are.
This schematic is an 'add-on' and if installed properly
(by an electrician, preferably) absolutely 'fool-proof'.

https://dl.dropboxusercontent.com/u/937562/schematic.JPG

If you connect mains, the battery will start charging automatically.
If during the night mains fails, you may not even notice!
The fridge will be the limiting factor when running of the battery.

This set-up is quite common in marine environments.

Hope this helps.....

Gerard.



sionbach

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Jan 17, 2014, 9:59:29 AM1/17/14
to

Hi David. Thansk for your reply. There is no battery compartment in
this Hobby. Allso there isnt a charger in it either, only a transformer
that steps the electric down from 240vAC to 12vAC

'David[_15_ Wrote:
> ;113057']Hi
> Have you placed the battery in the battery compartment and connected
> it?
>
> I think it may well not be giving sufficient voltage out because you
> have
> discharged it by removing the 240 v hook up so not allowing the 240v to
> 12 v
> unit charge it.
>
> Also when running 12v equipment when on hook up it is usually a
> requirement
> to have a battery in place.
>
> I do not know Hobby caravans but I never had a caravan that did not have
>
> full 240v and 12 v.
>
> Regards
> David
>
>
>
>
>
> "




--
sionbach

Harry Bloomfield

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Jan 23, 2014, 2:11:17 PM1/23/14
to
I'm wondering if it is really 12v AC, as it would seem so utterly
pointless to have an 12v AC supply. Only incandescent lamps would be
able to run on the AC supply.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk


Harry Bloomfield

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Jan 27, 2014, 8:29:25 AM1/27/14
to
Gerard submitted this idea :
> If during the night mains fails, you may not even notice!
> The fridge will be the limiting factor when running of the battery.
>
> This set-up is quite common in marine environments.
>
> Hope this helps.....
>
> Gerard.

Fridges are not powered from 12v, they either run on gas or mains.
Sometimes the do however require a 12v supply just for their control
circuits for use on gas.

Dougal

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Jan 27, 2014, 9:05:00 AM1/27/14
to
On 27/01/2014 13:29, Harry Bloomfield wrote:
> Gerard submitted this idea :
>> If during the night mains fails, you may not even notice!
>> The fridge will be the limiting factor when running of the battery.
>>
>> This set-up is quite common in marine environments.
>>
>> Hope this helps.....
>>
>> Gerard.
>
> Fridges are not powered from 12v, they either run on gas or mains.
> Sometimes the do however require a 12v supply just for their control
> circuits for use on gas.

Possibly true for current production models: not so for older ones. Very
few would, however, attempt to run a 12V 'fridge from a battery supply
without a functioning means of charging.

Dougal

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Jan 27, 2014, 9:08:42 AM1/27/14
to
On 27/01/2014 13:29, Harry Bloomfield wrote:
> Gerard submitted this idea :
>> If during the night mains fails, you may not even notice!
>> The fridge will be the limiting factor when running of the battery.
>>
>> This set-up is quite common in marine environments.
>>
>> Hope this helps.....
>>
>> Gerard.
>
> Fridges are not powered from 12v, they either run on gas or mains.
> Sometimes the do however require a 12v supply just for their control
> circuits for use on gas.

Possibly true for current production models: not so for older ones. Very
few would, however, attempt to run a 12V 'fridge from a battery supply
without a functioning means of charging.

There is usually no means of temperature control with 12V-powered units
which renders them unsuited to continual operation.

Harry Bloomfield

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Jan 27, 2014, 9:36:12 AM1/27/14
to
Dougal was thinking very hard :
I must say I have never come across one and thinking about it, it 12v
running would be entirely pointless... I do accept there are 12v
operating fridges, I have one myself, but the 12v is only intended to
be used whilst travelling and in no way matches the cooling needs for
longer.

Harry Bloomfield

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Jan 27, 2014, 9:42:40 AM1/27/14
to
on 16/01/2014, sionbach supposed :
> Hi everyone, been searching internet for a week or so now trying to
> install a battery in a hobby 720 2002 european version. Ive also phoned
> a few places but once I tell them I have a hobby the mood changes and
> most becomes unhelpfull.

I've been rather too busy to give this much time, but here goes...

First, I am still not entirely convinced that your existing 12v supply,
is AC, because you mention installed appliances which so far as I know
only come in 12v DC versions. There just would be no point in
installing 12v AC at all. You mentioned a Truma fan, a car type radio
and I assume a 12v water pump. Feed such a radio AC and it will self
destruct. Rather I think your problem with the radio is lack of current
or voltage (drop).

Now assuming it is DC, you would need to install a modern 13.8v 15 or
20amp charger /power supply, a battery and a suitable 12v fuse panel,
pick up the existing wires for your existing 12v equipment and maybe
more. When on mains, everything would automatically work on the PSU,
but when off mains it would run on battery.

Installing such would be quite an involved job, so it would be
pointless attempting it with any expertise.

Woody

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Jan 27, 2014, 12:08:06 PM1/27/14
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"Harry Bloomfield" <harry...@NOSPAM.tiscali.co.uk> wrote
in message
news:mn.db727de1a4...@NOSPAM.tiscali.co.uk...
Surprisingly Harry, even today most car radios have a diode
in series with the incoming supply or a reversed diode
across it to blow the fuse. That sits before the power
switch.

As for an earlier comment, I have been a caravanner for
nearly 40 years and I have <never> come across a caravan
where the fridge is connected in any way to the caravan
battery for cooling purposes. Fridges pull around or north
of 10A and would kill a battery in no time. As has also been
said, 12V operation is only intended to keep an already
chilled fridge cold: there is no temp control on 12V and if
the outside temp is not that much above the inside of the
fridge it will freeze up frighteningly quickly.

Harry Bloomfield

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Jan 27, 2014, 12:15:27 PM1/27/14
to
Woody expressed precisely :
> Surprisingly Harry, even today most car radios have a diode in series with
> the incoming supply or a reversed diode across it to blow the fuse. That sits
> before the power switch.

Possibly, but not something I would rely on being fitted.
>
> As for an earlier comment, I have been a caravanner for nearly 40 years and I
> have <never> come across a caravan where the fridge is connected in any way
> to the caravan battery for cooling purposes. Fridges pull around or north of
> 10A and would kill a battery in no time.

Correct!

> As has also been said, 12V operation
> is only intended to keep an already chilled fridge cold: there is no temp
> control on 12V and if the outside temp is not that much above the inside of
> the fridge it will freeze up frighteningly quickly.

I have never suffered that.

Tim+

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Jan 27, 2014, 4:11:39 PM1/27/14
to
Harry Bloomfield <harry...@NOSPAM.tiscali.co.uk> wrote:
> Gerard submitted this idea :
>> If during the night mains fails, you may not even notice!
>> The fridge will be the limiting factor when running of the battery.
>>
>> This set-up is quite common in marine environments.
>>
>> Hope this helps.....
>>
>> Gerard.
>
> Fridges are not powered from 12v, they either run on gas or mains.
> Sometimes the do however require a 12v supply just for their control
> circuits for use on gas.


Most caravan fridges are 3 way, gas, 12V and mains. 12V operation is
limited to use whilst towing due to the power consumption.

Tim

Chris J Dixon

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Jan 28, 2014, 4:49:15 AM1/28/14
to
Tim+ wrote:

>Harry Bloomfield <harry...@NOSPAM.tiscali.co.uk> wrote:

>> Fridges are not powered from 12v, they either run on gas or mains.
>> Sometimes the do however require a 12v supply just for their control
>> circuits for use on gas.
>
>Most caravan fridges are 3 way, gas, 12V and mains. 12V operation is
>limited to use whilst towing due to the power consumption.

Indeed so. I do know someone whose motorhome has a compressor
fridge which is 12 V only, but he hasn't found a way of keeping
it running without hookup or generator.

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

Plant amazing Acers.
Message has been deleted

Woody

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Jan 28, 2014, 6:41:11 AM1/28/14
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"Tom" <m...@privacy.net> wrote in message
news:XnsA2C373624...@news.datemas.de...
> Tim+ <timdow...@yahoo.co.uk> wrote in
> news:1997564058412524023.00759...@news.eternal-
> september.org:
> I have a 2008 Dometic fridge in my Swift. It needs the 12v
> on at all
> times, irrespective if it is running gas or mains, or it
> simply refuses to
> work at all. According to the technical manual for it I
> managed to get
> hold of when I thought it was faulty, this is the way it
> was designed to
> work.



Agreed it needs 12V for the control circuits (now very
common) and interior light of not on mains, but the cooling
does NOT run off 12V except when towing where the power
comes from the towing vehicle.
Message has been deleted

Woody

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Jan 28, 2014, 12:56:30 PM1/28/14
to
"Tom" <m...@privacy.net> wrote in message
news:XnsA2C3B41CD...@news.datemas.de...
> "Woody" <harro...@ntlworld.com> wrote in
> news:lc850h$pbj$1@dont-
> email.me:
> No, not 'if not on mains'. Even if it _is_ on mains, it
> still needs the
> 12v from the battery or it won't run. Which is a bit
> bizarre as the 12v
> could easily be derived from the mains if hooked up. But
> no, it's a
> completely seperate feed from the battery. I've no idea
> why - probably
> a cost saving exercise by the bean counters at Dometic.
>
>> but the cooling
>> does NOT run off 12V except when towing where the power
>> comes from the towing vehicle.
>
> Agreed.
>


Sorry, grammatical error. My fridge interior light will work
from 12V if the 12V supply is on, but also from the fridge
mains supply if the 12V supply is off.

Gerard

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Jan 29, 2014, 5:20:27 AM1/29/14
to
"Harry Bloomfield" <harry...@NOSPAM.tiscali.co.uk> schreef in
bericht news:mn.db297de1c2...@NOSPAM.tiscali.co.uk...
>
> Fridges are not powered from 12v, they either run on gas or mains.
> Sometimes the do however require a 12v supply just for their control
> circuits for use on gas.
I have not checked in for a while, but I see there is a
misunderstanding.
- Fridges DO run on 12 V while driving.
- The fridges' 12 V is connected directly to the car, never to the
van's 12 V circuits.

However:
Looking at the diagram I posted, it's possible to let the inverter
make 230 V from the 12 V battery. Quite handy on one or two night
stop-overs without hook-up. In this situation the use of the fridge on
230 V limits the life of the battery to few hours. Beter use butane
instead.

Hope this clarifies my earlier posting.

Gerard.

bert

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Jan 29, 2014, 6:18:28 AM1/29/14
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In message <a4ydnRfw7sv29XvP...@eclipse.net.uk>, Dougal
<DougalATHisKennel.free-online.co.uk@?.?.invalid> writes
12v on a fridge is designed for use when the van is being towed and the
supply comes from the towing vehicle's alternator. A battery on its own
would be flattened very quickly.
As already mentioned modern fridges do require a low power 12v supply
for control purposes
--
bert

A...@hotmail.com

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Jan 30, 2014, 11:27:20 AM1/30/14
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"Tim+"  wrote in message news:1997564058412524023.00759...@news.eternal-september.org...
Where did the idea come from that fridges on not powered by 12 V.
 
You can buy fridges and deep freezers  running on 12V.
 
 
or you could try
 
 
The reason they are not fitted in vans is that they are to heavy on juice for just one 110 amp hour battery
 
I sure that you know that gas fridges must be sealed from the van and vented to the outside only. Bit difficult on a boat if the fridge is below the water line.
 
But having said that it can be achieved. 24 hours running on 12v would kick the ring out of one battery. Have six and you will do better. Yes I know, weight.
 
Mike

Woody

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Jan 30, 2014, 12:05:36 PM1/30/14
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<A...@hotmail.com> wrote in message
news:N3vGu.323$fx7...@fx16.am4...
I think you have misinterpreted the thread Mike. ALL such
fridges run off 12V agreed but in a caravan installation
they do not run off the caravan battery, only from the
towing vehicle when its engine is running.

I don't know about boat fridges, but caravan fridges do not
have any temperature control when running on 12V - it is
just intended to keep an already cold fridge cold until it
can be changed to mains or gas, both of which <are>
temperature controlled.

Harry Bloomfield

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Jan 30, 2014, 2:01:19 PM1/30/14
to
However, this is a caravan newsgroup and the question was caravan
related, so what is available in boating circle is not really relevant
and in this case - not even practical.

Daniel Marsh

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Jun 11, 2023, 2:07:35 AM6/11/23
to
Hi Tim
So in you're original post you mentioned 12v ac on a euro Van, This is Correct to my knowledge Hoddy/Deff/Etc
Reduce down 230v ac to 12v ac for all there systems not dc when you put solar panels and install batteries it can be done but the systems needs a lot of work.
to make the control panels take the DC, For example you can plug in your 13pin from the car and go in the van and the inside light will work that are AC but its DC coming from the car so
it doesn't make sense, so it can be done But I would get a Hobby specialist to look at it for you try A+E leisure in Northwich Cheshire.
Its not a Job I would try and Do and I'm an AWS caravan engineer. This is why we you are getting negativity from places you are contacting its a lot of work and Complicated.Good Luck
Dan
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