ABB Motor Load Monitors

The Cm-Lwn Relay Is From The Cm Motor Load Monitors Range. This Relay Operates With A Rated Control Supply Voltage Of 24-240 V Ac / Dc, 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 0.5-5 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.