How do you select transformers?

1. Determine primary voltage and frequency.

2. Determine secondary voltage required.

3. Determine the capacity required in volt-amperes. This is done by multiplying the load current (amperes) by the load voltage (volts) for single phase. For example: if the load is 40 amperes, such as a motor, and the

secondary voltage is 240 volts, then 240 x 40 equals 9600 VA A 10 KVA (10,000

volt-amperes) transformer is required. ALWAYS SELECT THE

TRANSFORMER LARGER THAN THE AC TUAL LOAD. This is done for safety purposes and allows for expansion, in case more load is added at a later

date. For 3 phase KVA, multiply rated volts x load amps x 1.73 (square root of 3)

then divide by 1000.

4. Determine whether taps are required. Taps are usually specified on larger

transformers.

5. Use the selection charts in the Acme catalog.

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