ABB 1SBL411024R8500 3-Pole Capacitor Switching Contactor

Description

• The ABB 1SBL411024R8500 UA75..RA 3-pole contactor is a robust solution tailored for demanding capacitor switching applications, particularly those characterized by peak currents significantly exceeding the nominal rms current. These contactors are supplied as comprehensive units, complete with integral damping resistors, effectively eliminating the need for additional inductances that are commonly associated with such applications.

• Safety is a top priority when dealing with capacitor switching, and this contactor prioritizes safety by stipulating that capacitors must be discharged to a maximum residual voltage of no more than 50 V before any re-energization can occur during the contactor's closing operation. In terms of longevity and reliability, this contactor sets a high standard, boasting an impressive electrical durability rating of 250,000 operating cycles when the operational voltage (Ue) is below 500 V and 100,000 operating cycles for voltages ranging from 500 V to 690 V.

• One of the standout features of the UA75..RA contactors is their innovative front-mounted block. This unique design element facilitates the sequential insertion of three damping resistors into the circuit, effectively curbing the current peak during the energization of the capacitor bank. Furthermore, the contactor's connection scheme ensures the precharging of capacitors, effectively mitigating the second current peak that often occurs upon the closing of the main poles. The inclusion of these resistors ensures efficient damping of the highest current peak during capacitor switching, regardless of its magnitude.