1909 Ge Slipring Motor And Controller

[dps]

I'm helping to restore a carousel, using the original motor and controller for authenticity.

Motor, GE I-3-10A-1200 Form L (1909)

Controller GE-T-133-R, 8 step + shorting.

Resistors were lost and there is no record.

Have some S/H resistors and trying to establish suitability.

Anyone have any info. on this motor and controller?

I know the theory and and knew this class of motor from the past. Will set it up as best I can,

but would like some confirmation if original documents are available. GE have no records any more.

Thanks, Des Sainsbury.

[marke]

Hello Des

 

Welcome to the forum.

 

This sounds like an application where the secondary resistance start is used to give a "soft" start rather than a high torque start.

Du you have information on the rotor voltage and current from the nameplate?

 

Best regards,

Mark.

[dps]

Hello Des

 

Welcome to the forum.

 

This sounds like an application where the secondary resistance start is used to give a "soft" start rather than a high torque start.

Du you have information on the rotor voltage and current from the nameplate?

 

Best regards,

Mark.

Thanks marke,

Apologies for delay in reply.

Intent is for a soft start, with 1st notch about 20% speed.

No nameplate, but believed to be 10 hp, 208 V 3 ph. Rotor Volts 88 V, measured, current (calculated from primary), 100 Amp.

dps

[marke]

Hello Des

 

The rotor resistance determines the speed torque curve of the motor.

The maximum torque occurs when the secondary resistance is equal to the reactance of the rotor.

In this case, I expect that you do not want the maximum torque, rather the speed will be determined by the rising torque of the driven load and the falling torque of the motor operating above the slip of maximum torque.

 

As you will not know the torque curve of the driven load, you will have to find the value by trial and error.

I would calculate the resistance to give you maximum torque at zero speed and multiply this by around 4 and try it to see what speed the load settles at.

To calculate the resistance at zero speed, divide the rotor current into the rotor voltage, then divide by root 3 for star connected resistors.

 

Good luck,

Mark.