## DC Test - Determines R1
- Connect any two stator leads to a variable-voltage DC power supply
- Adjust the power supply to provide rated stator current
- Determine the resistance from the voltmeter and ammeter readings
## For a Delta-Connected Stator
## Determination of Induction-Motor Parameters
## Simplified Equivalent Circuit
## How Is the Blocked-Rotor Impedance Divided?
## Determination of Induction-Motor Parameters ## No-Load Test - Determine the magnetizing reactance, XM and combined core, friction, and windage losses.
- Connect as for blocked-rotor test (next slide).
- The rotor is unblocked and allowed to run unloaded at rated voltage and rated frequency.
## Determination of Induction-Motor Parameters ## At no-load, the speed is very close to synchronous speed – the slip is =0, causing the current in R2/s to be very small, and will be ignored i the calculations. ## IM>>Ife, so I0 = IM.
## Example 5.16 ## The following data were obtained from no-load, blocked-rotor, and DC tests of a three-phase, wye-connected, 40-hp, 60-Hz, 460-V, design B induction motor whose rated current is 57.8A. The blocked-rotor test was made at 15 Hz.
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