PTO standby generator repair

P

pat kcotnit

Member

Location

Oot and aboot

• Jul 21, 2017

• #1

We had a power failure recently and discovered our old froment single phase PTO generator is faulty (only putting out 115 volts according to our electrician). Is it worth getting it looked at (possibly rewound if necessary) or would it be more economical to buy a new one.
If it is worth having someone look at it does anyone have any suggestions to who would be best to contact to do so (central Scotland). Awaiting on one firm to get back to me from west of Glasgow at the moment. Not really wanting to waste time and money on electrical engineers inspecting/stripping down our old one for them to turn round and say no buy a new one after running up a bill that would go a long way to buying a new one.
TIA

 

Pheasant Surprise

Member

Location

Woodbridge, Suffolk

• Jul 21, 2017

• #2

How many kVa is the current one? Were you quoted a figure to get it rewound?

 

F

Frodo2

Member

• Jul 21, 2017

• #3

What are you powering with it? I would be tempted to get one with its own engine. I used to have a 3phase froment PTO generator and upgraded to a used generator with its own engine and auto switch over.

 

Blue.

Member

Livestock Farmer

• Jul 21, 2017

• #4

Stick it on a pallet and send it to pickhill engineers thirsk.

 

M

manhill

Member

• Jul 21, 2017

• #5

115/230 step up transformer possibility?

 

Pheasant Surprise

Member

Location

Woodbridge, Suffolk

• Jul 21, 2017

• #6

I don't think Froment make PTO generators any longer, concentrating on the more lucrative market of PTO dynos. They'd still be able to be rewound though or fitted with replacement voltage regulators etc.

There's a couple of places that sell PTO generators based around the Italian Linz made alternators and they look good quality. Otherwise could get ones of places like Machinemart, I think they're badged Clarke units.

 

3

335d

Member

• Jul 21, 2017

• #7

As above, what size of generator. Also has it the option to switch between 115V and 230V? I'm only familiar with smaller generators which have two 115V windings and use a switch to either connect them in parallel for 115V or connect them in series for 230V

 

P

pat kcotnit

Member

Location

Oot and aboot

• Jul 21, 2017

• #8

It is a 40 kva, 167 amps single phase PTO powered froment magnate (probably about 40+ years old). Haven't had a quote yet to repair (company I phoned never phoned me back!). I am just thinking someone else has probably had one fail and had it repaired and know the rough cost to do so and if they have was it worth repairing versus the cost of a new one.

 

D

defender

Member

Location

Aberdeenshire

• Jul 21, 2017

• #9

If it is putting out any voltage it is worth looking at repairing , it is possibly one of the diodes blown on the board at the back of the windings . This should be the first check
and very simple to do yourself with a meter . Just disconnect one end of the diode and check if current passes one way and not the other . if it is blown and passes current both ways replace it . cost will be less than £5 for diodes

 

D

defender

Member

Location

Aberdeenshire

• Jul 21, 2017

• #10

Rewind price might give you a fright
Magnate generators are still available but now from Roland Bradley
they have spares available for all ages I believe
http://www.bradleysptogenerators.com/

 

JPM

Member

• Jul 21, 2017

• #11

This doesn't apply to this generator but I once bought an old pto one from a dairy farm nearby. I wired an extension lead into it and it wouldn't produce any power. After some research online I plugged my 240v drill into the extension lead(wired into the generator) & with a drill bit in that drill I connected my cordless drill onto the drill bit and ran the 240v drill in reverse for about a minute(effectively making the drill a small generator) Plugged an inspection lamp into the extension lead..... fired up the genny a once she was at 540revs there was a loud cracking noise and away she went[emoji1] worked fine ever since. Think the genny had lost its magnetism.

Just incase anyone has that issue I thought I'd post that long winded story [emoji23]

 

Zetor

Member

Location

Northumberland

• Jul 22, 2017

• #12

JPM said:

This doesn't apply to this generator but I once bought an old pto one from a dairy farm nearby. I wired an extension lead into it and it wouldn't produce any power. After some research online I plugged my 240v drill into the extension lead(wired into the generator) & with a drill bit in that drill I connected my cordless drill onto the drill bit and ran the 240v drill in reverse for about a minute(effectively making the drill a small generator) Plugged an inspection lamp into the extension lead..... fired up the genny a once she was at 540revs there was a loud cracking noise and away she went[emoji1] worked fine ever since. Think the genny had lost its magnetism.

Just incase anyone has that issue I thought I'd post that long winded story [emoji23]

Click to expand...

Yes sometimes you need to give to re energise the exciter circuit can be common on older generators without avr, I've had this with mine I just flashed it with a 12v battery & jump leads

 

wdah/him

Member

Location

tyrone

• Apr 6, 2024

• #13

Along a similar set up here. Decided to run out 25kva generator today, pto driven. Hasn’t been run in I don’t know how long but last time it was it had to get a capacitor, maybe two. Problem was the frequency was off the scale when at 230v. Today at 230 v the frequency is about 63 hz. Can this be brought down to more normal or will it be ok. Tried in on a grinder and yep confirms that frequency is too high. At 20v it is about 58hz. Just leaving it running but not powering anything as it has been a few years since it last went.
Funny thing is the petrol generator we never think what way it is performing just pull it and work away.

 

sjt01

Member

Mixed Farmer

Location

North Norfolk

• Apr 6, 2024

• #14

wdah/him said:

Along a similar set up here. Decided to run out 25kva generator today, pto driven. Hasn’t been run in I don’t know how long but last time it was it had to get a capacitor, maybe two. Problem was the frequency was off the scale when at 230v. Today at 230 v the frequency is about 63 hz. Can this be brought down to more normal or will it be ok. Tried in on a grinder and yep confirms that frequency is too high. At 20v it is about 58hz. Just leaving it running but not powering anything as it has been a few years since it last went.
Funny thing is the petrol generator we never think what way it is performing just pull it and work away.

Click to expand...

Frequency will depend on PTO speed. Did you have it in an Eco pto gear? If frequency is too high, then drop the revs a little. You will need to be a bit over 50 Hz at no load as the pto speed will drop a bit as you put load on.

 

wdah/him

Member

Location

tyrone

• Apr 7, 2024

• #15

At 50 hz. It is less than 200v. About 180. Does it need smaller capacitors?

 

sjt01

Member

Mixed Farmer

Location

North Norfolk

• Apr 7, 2024

• #16

wdah/him said:

At 50 hz. It is less than 200v. About 180. Does it need smaller capacitors?

Click to expand...

Depends on the design, possibly needs adjustment to the AVR. As you mention capacitors, I would guess it is single phase, I am more familiar with 3 phase.

 

mengeleguru

Member

Location

Derbyshire

• Apr 7, 2024

• #17

Bradley’s Pto Generators Ltd make good units
Ireland.