Single Phase Thyristor Power Switch for Duct Heaters – POW-1-ZC

Libratherm offers a single-phase heater power regulator model POW-1-ZC-XX for electric power control of resistive heating loads operating on single-phase 230VAC. This regulator accepts the user-selectable DC control signal of 0-10V and 4-20mA and can be easily interfaced with BMS, DDC, PID, or PLC. An external potentiometer can also be used for manual control. The On-Off duty cycle of voltage across the heaters can gradually vary proportional to the control signal. For a preset cycle time of 4 seconds, 50% power will be delivered by keeping the heater ON for 2 seconds and OFF for 2 seconds.

The facility is also provided to protect against the regulator’s overheating. Under normal conditions, the built-in thermostat switch will remain closed and will open when the device or heat sink temperature crosses around 90oC. The user can connect an external alarm relay to the interlock. Under normal conditions, the external relay will remain energized, and in case of overtemperature, the relay will de-energize.

Auto control is done through an external signal of 0-10V, and manual control is done using an on-card preset that is user-selectable using a jumper link.

This model POW-1-ZC-XX is available in a rugged powder-coated metal enclosure and can be easily fitted inside the panel. The terminal connection diagram and other settings on the top surface are lasers marked to facilitate the user for the wiring and operation of POW-1-ZC-XX.