1SVR508211R0100

The ABB 1SVR508211R0100 (CT-SDC.22) is a high-quality electronic star-delta timer relay designed for reliable three-phase motor starting and industrial automation applications. Manufactured by ABB, this timer belongs to the CT-C series and provides a dedicated star-delta timing function with seven adjustable timing ranges covering 0.05 seconds to 10 minutes. It features a fixed star-to-delta transition time of 50 milliseconds, helping coordinate the switching sequence between star and delta contactors. The timer operates with a rated control supply voltage of 24–240V AC or 24–48V DC and features two normally open output contacts rated at 250V and 4A.

The ABB CT-SDC.22 star-delta timer relay is designed for motor starting circuits that require an automatic transition from star connection to delta connection after a preset time interval. During the starting process, the motor initially operates in star configuration to reduce starting current. Once the selected starting period has elapsed, the timer initiates the transition to delta operation, allowing the motor to continue running under its normal operating configuration. Its adjustable timing settings make it suitable for different motor starting requirements.