How to size a Thyristor Power Controller

The formula below provides a simple method to calculate the thyristor current for typical resistive loads. The calculated value of I should then be multiplied by 1.2 (safety margin) to allow for variations in supply voltage and other tolerances of the load.

Single Phase (1PH)

Single Phase (1PH) Thyristor Sizing Tool

W Clear
Vac Clear
Amps
Amps

Three Phase (3 or 4 wire load, 2PH or 3PH)

Three Phase (3 or 4 wire load, 2PH or 3PH) Thyristor Sizing Tool

W Clear
Vac Clear
Amps
Amps