In SCR converters, or AC controllers, a high rate-of-rise in anode-to-cathode voltage, or dV/dt, occurs when a SCR ceases conduction, or when another SCR in the circuit is gated into conduction. High peak voltage is produced when an inductive circuit connected to the SCR is interrupted. The peak and rate-of-rise (dV/dt) of the SCR voltage must be limited to avoid erratic circuit operation and device damage. Connected anode to cathode, the snubber circuit resistor/capacitor limits dV/dt and the metal-oxide-varistor (MOV) limits peak voltage.
The TSTB120-1 snubber board has voltage and current transducer circuits that can be input into a microprocessor for voltage and current control in a 12-pulse bridge rectifier application.
Typical uses would be in battery charging applications where voltage and current are constantly monitored.