Monday, August 03, 2009

Generator assembled

Generator assembledHere's the generator after assembly.

This was actually put together last week but, because of the interest I've sparked, I wanted to wait until I had a decent picture and more details on the maker before posting this.

My generator is a rather battered looking version of one of these Transmotor generators, a 100amp DCG-55 EVR to be precise.

What really surprised me, though it shouldn't, was just how silky smooth the generator shaft now turns in it's new bearings. 12 quid (say 24 US$) for the pair.

Turning the shaft before changing the bearings gave a kind of grinding feel, and the generator had been running really hot, however when I took the bearings out they both felt like they turned smoothly with no noticeable play in them. Anyway, because of that, I was starting to doubt that just replacing the bearings would revitalise the generator.

Now, after seeing a shiny new one, I'm almost inspired to give mine a lick of paint before putting it back into service.


  1. For some reason, I have in my head a warning remembered from years ago:

    Don't run bearings jammed on your finger using compressed air or similar, in case they seize.

  2. Mmmmmm I know nothing! they would have to get hot to sieze so I guess that your fingers would burn first? "Hang the expense give the cat a goldfish" paint it up and do a "Proper Job"

  3. Anonymous1:45 PM

    Quite an advanced little unit:
    "The voltage control consists of a low frequency pulse width modulating transistor control with an integrated regenerative feedback with RC coupling."
    It doesn't seem possible that would have been original equipment back in the mid sixties.

  4. Hi anonymous

    Is it possible to explain what that really means?

    I, for one, certainly don't understand it.



  5. Anonymous3:17 PM

    No idea, really. It does SOUND quite fancy though, don't you think?

    There is a detailed manual for a different model -- a DCG-56 EVRP -- that explains where the magnetic fields come from. There is a stationary field coil like a belt around the middle of the rotor. When it is energized the rotor becomes magnetic.

    The pulse width modulation jazz is about regulating the strength of the field coil and thereby the output voltage, in response to load and speed. The fact that that regulation is switched, not linear is pretty fancypants for a mid sixties industrial unit, it seems to me.

  6. Hi Anonymous

    It does sound good I agree. So much so that I'm now thinking of using it more actively, rather than only when the main engine runs.

    As to the sixtys install, I suspect that was fitted more recently, as the mounting plate has been hacked about a bit.