ABB UA75-30-00RA 24V 50Hz / 24V 60Hz Contactor – 1SBL411024R8100
- Product Name : Contactor
- Auxiliary Contacts : 1 NO
- Poles : 3
- Product Class : Block Contactors
- Voltage : 24 V DC
- Terminal Type : Screw Terminals
The UA75..RA 3-pole contactors are specifically designed for capacitor switching in installations where peak currents can exceed 100 times the nominal RMS current. These contactors are supplied complete with damping resistors and are intended to be used without any additional inductances. Before re-energizing, it is crucial to ensure that the capacitors are fully discharged, with a maximum residual voltage at the terminals of ≤ 50 V. The UA..RA contactors offer excellent electrical durability, with a lifespan of 250,000 operating cycles for voltages below 500 V and 100,000 cycles for voltages between 500 V and 690 V. Each contactor is equipped with a special front-mounted block that facilitates the serial insertion of three damping resistors, effectively limiting the inrush current during capacitor bank energization. This setup also allows for capacitor precharging, reducing the secondary current peak that occurs when the main poles close. The resistor insertion helps to dampen even the highest current peaks, regardless of their intensity. The UA..RA series features a block-type design with three main poles, an AC-operated control circuit with a laminated magnet core, and compatibility with a wide range of accessories.