Powercraft/Wolf 720 watt generator fault
curls
The output from this generator is low to non-existent. If I plug a 500 watt drill in, it might turn
sometimes, but only between probably 10rpm and 200rpm, it's very erratic - guessing the speeds of
course - then it will stop altogether, and then maybe start up again, slowly.
There doesn't seem to be much that can be done with these other than maybe change the capacitor, but
my electrical knowledge is too lacking in such matters to even know if that could be the problem.
Is it a lost cause?
I originally got this from Freecycle knowing the genny side was faulty, in the hope I could make a
good one out of two - I have another with a duff engine. Turns out they are sufficiently different
that I can't do anything with them, so now I have two non-working genny's :)
cj
sounds like a great excuse to learn about generators (you can't make it any
worse)
Basically a generator is a spinning coil (or coils)of wire which spin in a
magnetic field usually generated by another coil of wire.( I'm sure you knew
this).
But did you know the field coil is usually DC whilst the armature is
producing AC.
Most generator have a rectifier pack or voltage regulator connected to the
field and these often go faulty.
Another common fault (with long unused sets) is sticking brushes.
Yes they DO have brushes these bring the AC output off the armature and can
stick in their guides giving symptoms as you describe.
Find the brush gear and measure the voltage with the set running also check
the field voltage out of the regulator.
Oh of course check that the field windings are ok.
Just a few pointers to get you on your way
HTH good luck
CJ
meow...@care2.com
How much work do you want to do on such a low value genset? You could
start by multimetering the physical generator while running to see
what voltages are where, and resistance testing the same while not
running.
I dont suppose its worthwhile to bodge the gen head onto the working
motor.
NT
Dave Liquorice
> The output from this generator is low to non-existent. If I plug a 500
> watt drill in, it might turn sometimes, but only between probably 10rpm
> and 200rpm,
Motors require significantly more power to start than run, in the order of
2 to 3 times. Though as yours does try I'd expect it to spin up
eventually. If you give the motor a spin by hand does it run? Can the
genset power a simple load like a light bulb? If does 60W without problem
cobble together a few more to up the load.
--
Cheers
Dave.
curls
>Hi
>sounds like a great excuse to learn about generators (you can't make it any
>worse)
>Basically a generator is a spinning coil (or coils)of wire which spin in a
>magnetic field usually generated by another coil of wire.( I'm sure you knew
>this).
>But did you know the field coil is usually DC whilst the armature is
>producing AC.
>Most generator have a rectifier pack or voltage regulator connected to the
>field and these often go faulty.
>Another common fault (with long unused sets) is sticking brushes.
>Yes they DO have brushes these bring the AC output off the armature and can
>stick in their guides giving symptoms as you describe.
I don't have a manual or brochure for this, but I'm sure I remember, when they were on sale in Aldi,
that the blurb said "brushless self-exciting."
curls
>How much work do you want to do on such a low value genset? You could
It's mostly a matter of having a lot of spare time, combined with a fondness for repairing just
about anything if it's possible. Saving money is a bonus of course, even if it's only a few quid.
>start by multimetering the physical generator while running to see
>what voltages are where, and resistance testing the same while not
>running.
This is where my knowledge is lacking. I'm happier with spanners in my hands than a multimeter.
>I dont suppose its worthwhile to bodge the gen head onto the working
>motor.
That was my original idea, but the crankshaft/armature shaft is a one piece thing, as are the
crankcase and one end of the generator case, so it's not feasible.
Still, I can always hack the armature off, stick a pulley on the shaft and use the engine to drive
something else. As the old saying goes, "It'll come in handy even if I never use it."
Thanks for all the replies.
curls
I tried it with an 11 watt flourescent handlamp. Depending on how the genny is feeling, it varies
from nothing to full brightness.
Dave Liquorice
> I tried it with an 11 watt flourescent handlamp. Depending on how the
> genny is feeling, it varies from nothing to full brightness.
Flourescent is a "nasty" load again like a motor and 11W isn't a big load.
Don't you have a nice tungsten lamp you can plug in? I suspect it might be
the regulator that has packed in. Have a dig about on the web, they aren't
rocket science maybe just a chunky diode and a capacitor. Probably a
single sealed unit but possibly available as a generic spare.
--
Cheers
Dave.
Pete C
> I'm expecting cries of "bin it" but it's worth a try.
>
> The output from this generator is low to non-existent. If I plug a 500 watt drill in, it might turn
> sometimes, but only between probably 10rpm and 200rpm, it's very erratic - guessing the speeds of
> course - then it will stop altogether, and then maybe start up again, slowly.
>
> There doesn't seem to be much that can be done with these other than maybe change the capacitor, but
> my electrical knowledge is too lacking in such matters to even know if that could be the problem.
Hi,
Try a google on 'generator field flashing'
There's some info about checking/flashing a brushless self exciting
generator here in a manual here.
<http://www.powertechengines.com/NewageData/
MarkonPartsServiceInstallation-105-english.pdf>
*If* it needs flashing it looks like you just need to connect a 12V
battery across the capacitor for a second.
If using a lead acid battery I'd also connect a fuse inline in case
something has shorted.
cheers,
Pete.
Pete C
> *If* it needs flashing it looks like you just need to connect a 12V
> battery across the capacitor for a second.
while the generator is running.
cheers,
Pete.
curls
Same behaviour with a 40watt table lamp as with the fluorescent and the drill.
It turns out the armature could be separated from the crankshaft so I took the lot apart and took a
photo. http://tinyurl.com/5nelwt
There are three pairs of wires from the stator. One pair goes to the 6uF capacitor which you can see
in the top middle of the black plastic piece. Another pair goes to the 230v socket, with the live
going through a reset switch first. The remaining two wires go to a 12v socket for battery charging.
And that's it.
The CBB61 capacitor seems to be only available from China, though there's a similar one on ebay, but
that's half the price of a new genny.
meow...@care2.com
> On Tue, 24 Jun 2008 15:06:19 -0700 (PDT), meow2...@care2.com wrote:
> >How much work do you want to do on such a low value genset? You could
>
> It's mostly a matter of having a lot of spare time, combined with a fondness for repairing just
> about anything if it's possible. Saving money is a bonus of course, even if it's only a few quid.
let the fun begin
> >start by multimetering the physical generator while running to see
> >what voltages are where, and resistance testing the same while not
> >running.
>
> This is where my knowledge is lacking. I'm happier with spanners in my hands than a multimeter.
all you need do is measure everything possible on voltage setting with
it going, and on resistance with it stopped. We can interpret from
there.
NT
meow...@care2.com
if it were that surely it would perform consistently badly. I suspect
a bad joint is more likely, which is generally an easy fix.
NT
meow...@care2.com
> On Wed, 25 Jun 2008 15:11:46 +0100 (BST), "Dave Liquorice" <allsortsnotthis...@howhill.com> wrote:
> >On Wed, 25 Jun 2008 12:10:12 +0100, curls wrote:
> >> I tried it with an 11 watt flourescent handlamp. Depending on how the
> >> genny is feeling, it varies from nothing to full brightness.
>
> >Flourescent is a "nasty" load again like a motor and 11W isn't a big load.
> >Don't you have a nice tungsten lamp you can plug in? I suspect it might be
> >the regulator that has packed in. Have a dig about on the web, they aren't
> >rocket science maybe just a chunky diode and a capacitor. Probably a
> >single sealed unit but possibly available as a generic spare.
>
> Same behaviour with a 40watt table lamp as with the fluorescent and the drill.
>
> It turns out the armature could be separated from the crankshaft so I took the lot apart and took a
> photo.http://tinyurl.com/5nelwt
>
> There are three pairs of wires from the stator. One pair goes to the 6uF capacitor which you can see
> in the top middle of the black plastic piece. Another pair goes to the 230v socket, with the live
> going through a reset switch first. The remaining two wires go to a 12v socket for battery charging.
> And that's it.
>
> The CBB61 capacitor seems to be only available from China, though there's a similar one on ebay, but
> that's half the price of a new genny.
6uF 250vac caps are used in fluorescent lights, motors, etc, and cost
2 or 3 squid max. From any tron component supplier. But thats
immaterial until you've found out whats wrong.
NT
The Natural Philosopher
is genraeted, they build up to a maximum.
However, surely field coils are excited with DC? perhaps there is a
rectifier block the far side of that capacitor that has gone partially phut.
Bob Minchin
There are downloadable manuals on the omega wolf website but not one for
this generator.
Bob
cj
AC field eh! isn't time a b*&"h seems only yesterday watching a pal try and
prove that a series genset won't generate if you short the output.
Oh well time marches on ... as for brushless systems some Kango sets circa
1970's tried this by using an offset field biased with a capacitor and a
squirrel cage type armature IIR.
Sorry I can't be of further help as obviously my obsolete training and
experience is no longer the "Usual" but one thing that will not change is
that a generator makes electricity by moving a conductor across a magnetic
field,so good luck in your endeavours.
CJ
Tim..
"cj" <m...@here.com> wrote in message
news:BKmdndlIPb8C_vzV...@bt.com...
ALL of todays modern 3000rpm generators, and definately the throw away style
2 strokes use a spinning DC field and the AC power comes off the stationary
armature- i.e. NO brushes.
The OP probably has a shorted field or more likely expired diodes (yes,
very cheap and nasty) on the field coil. You will need to strip the spinning
part out of the generator and replace the diodes, and check the resistance
and insulation of the coil.
It's far from unheard of in this league of machine for the windings to move
slightly or there be sufficient 'slop' in the bearings for the field coil to
contact the case or armature and wear it away / short it.
Tim..
curls
>The Natural Philosopher wrote:
>> meow...@care2.com wrote:
>>> Pete C wrote:
The type of help you usually get from those places is, "Take it to your Powercraft dealer/repair
centre." I've not noticed many of those about though.
>There are downloadable manuals on the omega wolf website but not one for
>this generator.
I couldn't see where the manuals were on their website, assuming I was on the correct one. I have a
users manual of the type that says, "pull the string to start it," and not much else.
curls
I can't see any diodes unless they are hidden inside the coils. The only thing in sight is a
resistor between the two coils.
>It's far from unheard of in this league of machine for the windings to move
>slightly or there be sufficient 'slop' in the bearings for the field coil to
>contact the case or armature and wear it away / short it.
>
No signs of anything catching, rubbing, contacting or any other sort of *ing, except it won't *ing
work.
Bob Minchin
curls
electrician, who apparently "knows about generators", couldn't get it running any better than it
was.
I decided not to bother keeping the engine, so in the interests of recycling, I'm thinking about
hiding it in full sight in the allotment, as an appeasement to this months crop of travellers, who
will no doubt discover it during one of their nocturnal excursions.
Chris R
Hi Curls
I had the same problem, changed diodes etc and checked continuity on
the windings etc, after some more probing i changed the capacitor (8uF
440v) and hey presto the genarator is working again, I got the new
capacitor from Maplin Electronics http://www.maplin.co.uk/, Order no:
Motor run 440V 8uF RG64U at £3.43
The 2 diodes on the armature are hidden behind the resistior and are
1n5408 types that can be bought from Mode components for a very
reasonable price http://www.modecomponents.co.uk/
Hope this helps with your repair and gets you going if its not allready
fixed and helps someone in the future to repair there genarator also
Chris
--
Chris R
Generator Guru Ltd.
your problem. If you need spares for Powercraft Generators we have them in
stock. We are also happy to advise you on fault finding and repairing if
you need it. To purchase parts please see our website.
http://generatorguru.com/categories/Make-%26-Model/Powercraft/
--
phil...@gmail.com
spam
spam
spam
wonderful spam
wonderful spam
harryagain
"Generator Guru Ltd." <caedfaa9ed1216d60e...@example.com>
wrote in message
news:424c9$54fef521$cf3aab60$31...@news.flashnewsgroups.com...
load.
(Connected to the carburretor, some sort of centrifugal device) I would
check that the linkage is free to move first off.
Peter Parry
<caedfaa9ed1216d60e...@example.com> wrote:
>It sounds like the capacitor is faulty. Replacing the capacitor should fix
>your problem. If you need spares for Powercraft Generators we have them in
>stock.
Date: Tue, 24 Jun 2008 12:07:59 +0100
Message-ID: <cck16452rf4fktam1...@4ax.com>
One has to admire your stellar customer service and speed of response,
it only took you 7 years to reply. Goodness knows how long it would
take to get the spares off the shelf, 10 years at least at that rate.
Mr Ian Clement
Hi there hope you can help.I have replaced almost everything on this generator
except the capacitor and the diodes I just cant find the diodes so I can test
them .Can you tell me where they are located? I am at present driving the
generator with a high speed drill and can only get approx. 5 volts output
,would faulty diodes or capacitor cause this Cheers ian C
--
for full context, visit https://www.homeownershub.com/uk-diy/powercraft-wolf-720-watt-generator-fault-489242-.htm
Mr Ian Clement
replaced and tested everything on this 720 generator and I can still only get
7 volts A.C Output.I have ordered new diodes but cant find any markings on the
old diodes to confirm which way they face ,are they both facing the same way?
ie bands to the right or one left and one right?.I know I should have checked
them when I removed them but I was in a bit of a bad mood. Hope you can help
Cheers Ian C