The CM-LWN relay is from the CM motor load monitors range. This relay operates with a rated control supply voltage of 480-500 V AC, has a 2 x 1 c/o (SPDT) output with contacts rated at 250 V / 4 A and works according to the closed-circuit principle. Its measuring principle is based on the evaluation of the phase shift between the voltage and the current in one phase of single- or three-phase asynchronous motors (squirrel cage). The measuring circuit is designed for measuring voltages of 110-500 V AC and measuring currents of 2-20 A AC. The window (over- and underload) monitoring allows setting of two individual threshold values, one for maximum load and one for minimim load. The hysteresis is fixed at 4 ° related to the phase angle. The tripping delay is adjustable within a range of 0.2 to 2 s and the start-up delay within a range of 0.3 to 30 s. A sealable transparent cover for protection against unauthorized changes is available as accessory.
