[SEL] Generator hookup

[Richard Strobel]

Thanks Jim..that was very helpful.  I understand what you're talking about.

  As 250VDC is a very undesirable voltage, can I not hookup..say a 24vdc 
carbon pile regulator and get the output down to a decent regulated 24vdc.
  Just possibly the control panel for this gal is still up at the silver 
mine, which would be the ultimate.

  Another oddity about the generator is that the brushes do NOT have any 
braided wire attached to them.  Personally I don't like this and hopefully 
can replace them.

  It would look and perform better with 8 brushes and holders..will look 
into fabriating 4 more.

  I also think I know who's got a megger.

Thanks much for the reply
RickinMt.


----- Original Message ----- 
From: "Jim Dragoset" <Jdragoset at galvotec.com>
To: "The SEL email discussion list" <sel at lists.stationary-engine.com>
Sent: Wednesday, May 11, 2005 8:42 AM
Subject: RE: [SEL] Generator hookup


> Rick,
> You would expect an eight pole DC machine to have eight brushes spaced
> evenly around
> the commutator. They would in turn alternate +,- around so all the + 
> brushes
> would
> connect together and all the - brushes would connect together.
> A valid test would be to separate all connections and energize the field
> winding with a 12 volt battery.
> With the machine up to speed you should measure a voltage between any two
> adjacent brushes.
> Mark the field wire and brushes that are positive.
> You would also want to get a current reading through the field winding.
> If the field is intended to be self-excited, The current at 250 volts 
> should
> be under 1 amp
> which would correspond to under 48 milliamps with a 12 excitation.
> The field current test can be done with the machine no spun up.
> Be careful when you disconnect the 12 volts from the field as there will 
> be
> a high voltage back- kick.
> It is possible your machine only had four brushes originally 2+ and 2-
> Self excitation connection would be positive field wire to positive brush,
> negative field wire through rheostat (maybe as large as 250-500 ohms, 250
> watts) to negative brush.
> When you get it up to 250 volts try connecting the positive brushes 
> together
> and the negative brushes together provided their voltages are equal. check
> that current between two brushes is zero with no load.
> I would strongly recommend checking with a megger to 500 volts to make 
> sure
> all insulation of windings is good before attempting a rated output 
> voltage
> run.
> Good luck,
> Jim Dragoset,NOLA
>
> -----Original Message-----
> From: sel-bounces at lists.stationary-engine.com
> [mailto:sel-bounces at lists.stationary-engine.com]On Behalf Of Richard
> Strobel
> Sent: Tuesday, May 10, 2005 11:38 AM
> To: sel
> Cc: Elden DuRand
> Subject: [SEL] Generator hookup
>
>
>   Howdy all with Elden on the side.
>
>     Need some help getting this ole girl excited :-)
>
>    Generator rated at 250 VDC @ 16 amps.
>
>    If you can't read the legend on the pix. it's as follows:
>
>    A is connected to the 4 brushes
>
>    B is connected to one of the field coil winding
>
>    C looks like it's connected to the other winding in the field coil.
>
>    Pix at:
>
> http://community.webshots.com/photo/291395326/342708600ebaRxX
>
>   Tanks much!!
>
>   RickinMt.
> _______________________________________________
> SEL mailing list
> SEL at lists.stationary-engine.com
> http://www.stationary-engine.com/mailman/listinfo/sel
>
> _______________________________________________
> SEL mailing list
> SEL at lists.stationary-engine.com
> http://www.stationary-engine.com/mailman/listinfo/sel
>