Faulty welder generator ?

[sardine]

Ive beein offered a faulty welder generator with the GSA 190 alternator below that only generates when 12 v is put to the field winding , what is the likely repair for this and is it worth pursuing or is it a sign of a money black hole ?

 

[zzr1200]

Does the engine run, and can you use it for something else possibly, if not it could be a very black expensive hole.

Offer scrap money or less for the engine, if repairable it's a bonus......

 

[Barking Mat]

Does the engine run, and can you use it for something else possibly, if not it could be a very black expensive hole.

Offer scrap money or less for the engine, if repairable it's a bonus......

Sounds like the engine runs, but welder is playing up ???

 

[Tom O]

Even the pic shows sparks coming from it!

 

[GRW]

Putting 12v in off-load? Is that you substituting a battery for the AVR unit?
If so, then a replacement AVR might be all you need - but it's not certain.
A battery can pump more current in that can mask a fault with the exciter, but mist of the time a new AVR does the trick

 

[zzr1200]

Sounds like the engine runs, but welder is playing up ???

I agree, but I wouldn't pay for an alternator that's probably fubared..

 

[Barking Mat]

Was it you who was after a generator welder unit some months ago ?

 

[GRW]

I'm not familiar with that make/model of alternator or their prices - but it'd be worth finding out.
It's Italian.... and does look very much like those made by Zanardi (now part of MeccAlte Spa).
Is it possible it's a badged Zanardi I wonder? If it is then buying a Zanardi replacement might be cheaper..

 

[zzr1200]

Was it you who was after a generator welder unit some months ago ?

It wasn't me..

 

[frank horton]

Portable weld gen set
STUFF of dreams…

 

[Matrixx]

whatever supplied voltage to the exciter field is not working, putting a fixed voltage into the field will excite the alernator, if if produces voltage and current then in just needs the exciter suppply fixing.

 

[sardine]

whatever supplied voltage to the exciter field is not working, putting a fixed voltage into the field will excite the alernator, if if produces voltage and current then in just needs the exciter suppply fixing.

Exitation winding has gone then ?

 

[GRW]

Exitation winding has gone then ?

Or AVR possibly (hopefully)

 

[Matrixx]

Exitation winding has gone then ?

It could be, or the PMG if it has one, or the wireing, or the AVR, flashing the field will usally fire up the alternator if there is no residual voltage in the AUX winding.

 

[GRW]

If you can identify the Exciter + & - wires from the AVR, then remove them and put 2 wire extensions onto the disconnected wires.
Connect the + to the + terminal of a charged 12v battery. Keep the - free till you've started the genny.
Have a meter on the AC output, then touch the - wire to the battery- (touch so you can remove ASAP if it doesn't do as expected).
Output in the right ball-park then strong chance (not certain) it's AVR.
Engine suddenly labour's and or something starts to smell or smoke.... then alternator has major fault.

Do not maintain contact using battery for long - just enough to test. A battery has a lot more current than an AVR can deliver, so it can mask a diode or winding issue. IME though 49 of 50 x testing & getting output, a new AVR sorts it.