United Automation A447442-HV, HVAC Control, 209A 313A

The United Automation PR3 range of thyristor stacks provides full seamless control of three phase resistive loads, using two thirds control technique. These burst firing control stacks use fast pulse zero volts switching technology, to minimise flicker and eliminate RFI problems. They also incorporate an automatic resetting temperature trip, integral semiconductor fuses and heatsink. The two builds in this series are the 150kW and 225kW model. Both have easy access to signal and power terminals for simple installation.

Over temperature protection
Phase loss with auxiliary supply
Status LED indicator changes to continuous equal ON/OFF pulsing if the sensor fails