Motor stall current?

[steelefist]

I have my eye on a very cheaply priced used but newish 6.6hp DC 36V electric motor. There are no technical specs for the motor so I am trying to make educated assumptions b4 i commit to buying it. Do u reckon this is a series wound motor for this power output?
If so, does this mean that the no load current will be enormous, like in a car starter motor?

 

[TylerDurden]

do it look like this?

 

[Link]

What did it come out of?

 

[steelefist]

I have no images, I only know that it was brand new last year. heres the info i have.....

these parts are from a taylor dunn b200 see their web site. 12 mph as geared 2000 lb load capacity + 5000 lb tow capacity the motors are 36 volt general electric and the controllers curtis usa were in use up until last week and powerfull.

 

[Link]

Found this in a PDF about the B200.

Motor 6.6 HP; DC, separately excited

It's a sepex, meaning that it's basically a series wound (you can probably run it this way, too), but the current going to the field coils is dictated by the controller.

You'll need a special controller to run it in sepex mode. On the flip side, since it IS a sepex, you can just gear it as low as you can and decrease the field current to up the speed.

 

[TylerDurden]

It will weigh ~50lbs :|

 

[fechter]

It sounds like a golf car motor.
Most golf car motors have a splined shaft connection that would be difficult to use in another application, so you might check on that. Performance would be, well, like a golf car.
On a lighter vehicle like a motorcycle, it could be very fast.

 

[steelefist]

Cool so it could be extremely quick on the right frame! 50 pounds sounds very very heavy. The guy also has 1 off a si ilar vehicle which is used to pull light aircraft!!!!

The thing which is concerning me is the minimum amount of current this thing is gonna draw! It has the throttle and controller with it, so if i throttled it to the minimum point what kind of current will it be drawing. Will it be capable of spinning with only 5 amps or so?

 

[TylerDurden]

The thing which is concerning me is the minimum amount of current this thing is gonna draw! It has the throttle and controller with it, so if i throttled it to the minimum point what kind of current will it be drawing. Will it be capable of spinning with only 5 amps or so?

I doubt it. I have similar motors in my Citicars, and they are juicehogs. Typical draw is at least 50A - 200A.

FYI: advise against testing motor without load... dangerous overspeed likely.

 

[dirty_d]

yea, series wound motors don't have a no-load speed, mathematically for a perfect motor it would accelerate indefinitely since the field strength lessens as the current through the rotor decreases. that would never really happen though, the motor would just fly apart or stop accelerating due to friction. the stall current will be high. its probably in that pdf.