United Automation STOM-1, Thyristor Trigger Module

A solid state, microprocessor based device incorporating both Phase Angle and Burst Firing modes of power control (selectable).

Capable of controlling loads up to 25A at voltages up to 415 Vac
Can also be used for soft starting in Phase Angle and will automatically switch to Burst Firing at a preset signal level, remaining there even if the signal falls below preset level
18 Vac supply
0 to 30s adjustable ramp-up from cold
Control input 0 to 5V or 4-20mA current loop
Can be controlled by a temperature controller or PC

Mount on an adequate heat sink (heat sink compound stock no. 554-311 recommended). To comply with BSEN55014 in Phase Angle mode, a line filter should be used.

The number of complete mains cycles during fixed repeating periods (typically 1 to 10 seconds) is varied, thus altering the duty cycle or on-/off-time ratio. Trigger pulses coincide with the zero-crossing times of the mains supply thus ensuring no RFI is produced when using resistive loads.