THV compact, microprocessor based SCR power controllers feature programming keys and a digital display on the front, respond quickly to setting input changes in fast response applications and offer programmable phase control or zero-cross control. Set values and input signals can be checked and easily monitored by the front digital display keys but can also be made with an external setting unit like a variable resistor. Standard functions include gradient setting, ramp-up and ramp-down with a soft-start and soft-down, and high/low output limiters. It also includes three types of output modes and base-up setting (output bias). The THV operates at 100 to 240V AC and automatically selects power supply frequency 50 or 60 Hz.