Re: (ET) Motor question

[badfishracing att net]

On my E-15 motor, it was hit or miss as to whether or 
not the motor would turn.  The first time I powered it, 
the motor spun.  Must have had some type of residual 
field.  The next time it wouldn't.  If you spun the 
motor by hand a bit to start it, it would spin slowly.  
For the most part, it wouldn't turn without the field.  
This was with the motor detatched from the trans.

Darin Gilbert

> Rod,
> What I've learned from others on the list is that the 
series field on the ET 
> motors is just a compensating field to keep speed from 
dropping under heavy 
> load, i.e., it can't produce enough field to run the 
motor...Bob
> 
> >>> "Rod Hower" <Rod Hower ametek com> 8/9/2002 
7:31:27 AM >>>
> 
> I have a 13" compound wound 72 volt forklift motor in 
the garage.
> This motor can run (slowly) with a 12V automotive 
charger connected
> directly to the series field (no voltage on the shunt 
field).
> The no load current is about 4 times higher, but it 
still runs.
> 
> Since the ET has a compound motor, I figured I could 
do the same test.
> I jacked up the back wheels and put the charger across 
the series field,
> but the wheels didn't turn.  Has anyone ever tried a 
similar experiment?
> A friend told me it had a weak series field, but I 
would think it is strong
> enough
> to turn the wheels when its jacked up.  The motor was 
definitely drawing
> current, you could hear the transformer humming.
> 
> 
> Rod,
> What I've learned from others on the list is that the series field on 
> the ET 
> motors is just a compensating field to keep speed from dropping under 
> heavy 
> load, i.e., it can't produce enough field to run the motor...Bob
> 
> >>> "Rod Hower" <Rod Hower ametek com> 8/9/2002 7:31:27 AM >>>
> 
> I have a 13" compound wound 72 volt forklift motor in the garage.
> This motor can run (slowly) with a 12V automotive charger connected
> directly to the series field (no voltage on the shunt field).
> The no load current is about 4 times higher, but it still runs.
> 
> Since the ET has a compound motor, I figured I could do the same test.
> I jacked up the back wheels and put the charger across the series field,
> but the wheels didn't turn.  Has anyone ever tried a similar experiment?
> A friend told me it had a weak series field, but I would think it is 
> strong
> enough
> to turn the wheels when its jacked up.  The motor was definitely drawing
> current, you could hear the transformer humming.
> 
>