How to calculate open rotor voltage?

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theone
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Homework Statement


The AC power supply is connected to the stator terminals of the induction motor and the dynamometer. The rotor terminals are left open. The AC power supply is then turned on.
I need to find voltage between any two of the open rotor terminals.

Homework Equations

The Attempt at a Solution


I measured this as 102.6V but I'm not sure if I measured correctly. Is there a way for me to calculate it instead?
 
Attachments
  • Photo of a Lab-Volt wound rotor machine panel with a yellow-bordered rotor wheel, stator terminals labelled 1 to 4, rotor terminals labelled 5 to 9, and a motor rating label beneath.
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  • Wiring diagram of a 3-phase AC motor test setup: a 120/208V AC/DC power supply feeds the motor stator terminals 1 to 6, rotor terminals 7 to 9 are left open, and a dynamometer with a rheostat is connected to the power supply.
    Untitled10.png
    14.9 KB · Views: 459
There probably is. Have you done much electromagnetic induction before?
 
theone said:
The AC power supply is connected to the stator terminals of the induction motor and the dynamometer. The rotor terminals are left open. The AC power supply is then turned on.
I need to find voltage between any two of the open rotor terminals.

I measured this as 102.6V but I'm not sure if I measured correctly. Is there a way for me to calculate it instead?
The figures on the connector plate should be a clue to this. I'm having diffcuty reading it---does it show 120V per phase on the stator and 60V per phase on the rotor?

You applied what voltage, and was this 3ɸ?

Between what points did you measure the 102V?