ABB 1SBL411024R3600 3-Pole Capacitor Contactor

Description

• The ABB 1SBL411024R3600 UA75..RA 3-pole contactor is specifically designed for capacitor switching applications, particularly in installations where the peak current far exceeds 100 times the nominal rms current. This contactor is delivered as a complete unit with integrated damping resistors, and it is intended for use without additional inductances, as indicated in the accompanying table.

• For safe operation, it is imperative that the capacitors connected to the contactor are discharged, ensuring a maximum residual voltage at terminals of no more than 50 V before re-energizing during contactor closure. The electrical durability of the UA75..RA contactor is exceptional, with a rating of 250,000 operating cycles for operational voltages (Ue) less than 500 V, and 100,000 operating cycles for voltages ranging from 500 V to 690 V.

• The UA75..RA series is equipped with a front-mounted block that facilitates the sequential insertion of three damping resistors into the circuit. This feature is crucial for limiting the current peak during the energization of the capacitor bank. The connection design of the contactor also ensures capacitor precharging, mitigating the second current peak that typically occurs upon the closing of the main poles. The inclusion of resistors allows effective damping of the highest current peak during the capacitor switching process, regardless of its level.