Big generator?

Tim,

It could be what it says it is, look here

Martin P

I didn't say it's not what it says , just that there seems to be a lot missing from the description. Granted it's difficult to judge the scale of the thing, but my impression is of something in the 15 to 30 KVA region. 61.5 volts at 22.3 Amps is only 1370 VA, or a couple of horsepower (*if* it's single phase, of course). Having said that, it's own quoted exciter rating, 12 volts at 1.3 amps, is tiny, so it's just possible I've got completely the wrong idea of the scale!

If it was constructed as shown, apparently a motor-generator unit, what sort of machine would use AC excitation, which would not be synchronous with the main machine? (I'm out of my depth a bit here, but it's made me curious)

Cheers Tim

Tim Leech Dutton Dry-Dock

Traditional & Modern canal craft repairs

I wouldn't be surprised if it's a big heavy lump for the rating, particularly if it's ex-MOD or ex-BT. I bought a Metropolitan VIckers 110v dynamo which I thought was 15kW and turned out to be 1.5kW, for about 400lbs in weight.

Regards

Dan

It was and could still be common to have excitation provided externally, there's a big alternator locally that used an external source, as supplied.

Tom

must be the worst website I have ever seen. I agree with Tim, Anything that size built after 1900 must produce many times more output than quoted.

-- Dave Croft Warrington England

Possibly the vendor has got the details wrong, and the excitation voltage is for that particular machine, not something external.

It looks like the exciter is on the left-hand end of the lower machine, and that voltage is what it needs.

I guess it is a motor-generator set, and looking at the price and 'reserve not met' it will be another over-optimistically priced bit of hardware.

The postage would be a bit heavy.... :-))

Peter

-- Peter & Rita Forbes snipped-for-privacy@easynet.co.uk Engine pages for preservation info:

I did wonder if he had just read the exciter rating plate, but then where does the 'exc. 12 volts 1.3 A' come from ??

Cheers Tim

Tim Leech Dutton Dry-Dock

Traditional & Modern canal craft repairs

Yes, but AC excitation? I'm probably displaying my ignorance here, but I would have thought that a machine which used independent AC axcitation, not synchronised with the main machine, would produce some rather strange random waveforms? Someone please enlighten me if I'm wrong!

Cheers Tim

Tim Leech Dutton Dry-Dock

Traditional & Modern canal craft repairs

It would be rectified before being applied to the field, probably a big old selenium plate rectifier in there or the control cabinet.

Still seems a low voltage to me...

Kind regards,

Peter

Peter Forbes Prepair Ltd Luton, UK email: snipped-for-privacy@easynet.co.uk home: snipped-for-privacy@easynet.co.uk

note too, the cabinet behind the MG set. i wonder if it's part of the package? and you're right, it must be more power than that. sam