Old pto generator rebuild?

[jd24]

Hi we have old 3pt pto driven generator on the farm. I think it's about 25-30kw and dad used to hook it up whenever our power failed to keeping the milking parlour going. Used to happen quite a lot when I was younger.
Its been about 10 yrs since last used and when I tried to run it recently the voltage pulsed and only got to 150v ish. Can this be rebuilt for a reasonable price?

 

[jd6820]

Do you know how it is excited? Voltage regulator may be faulty? Does it read 50Hz on frequency when run at rated speed?

 

[jd24]

I will find out more. I believe the make is magnate

 

[Netherfield]

Brushes could be stuck/might need cleaning if it's been stood a while. Take the back cover off they're easy to see.

Does it have a flashing light which should then stay constant when at correct speed?

Single or three phase?

 

[ridger]

Do you know how it is excited? Voltage regulator may be faulty? Does it read 50Hz on frequency when run at rated speed?

It should be excited to be used after a few years idle?

 

[jd6820]

If you have a look on the plate (if it has one) they usually state what the method of excitation is. I believe PMG's fair better over time, but if the alternator field windings are good it could be a case of AVR faulty and a replacement may cure the voltage drop or as others have pointed out it needs exciting by inducing a voltage into the field windings. The fact you have voltage says something is occurring.

 

[X344chap]

N J Froment of Stamford who built the magnate series of pto generators are still in business but now part of the bigger ASCO group. Why not give them a call and see what they say?

 

[jd6820]

 

[jd6820]

I should also state that dealing with high voltage electrics if you aren’t absolutely sure about the working principles is dangerous. The supplied information is only a reference to give you a basic understanding of how the AVR gains it’s power supply to control the excitation (field) windings. Therefore regulating alternator output...