Description: All-electronic motor protector, the CEF1, utilises solid state electronics to provide maximum overload protection for motors up to 400 full load amps. Where a conventional thermal overload relay mechanically simulates the heat buildup in the motor (using bimetal elements), the CEF1 electronically simulates heat buildup using more precise solid state technology. Once the motor's current rating and the desired trip time have been set, the CEF1 monitors actual motor current through integrated current transformers. By combining the elements of time and current, the solid state electronics provide a very accurate simulation of heat buildup in the motor. Consequently, shut down of the motor will occur when the maximum allowable time/ current limits are reached. All CEF 1 models feature an adjustable degree of inertia, single-phase / phase-unbalance protection and individual LED fault indication. Units are also available which include thermistor over-temperature protection and an LED indication which flashes when the motor has reached 110% of rated current. This feature allows the user to load the motor to its full rated capacity without fear of harming the motor. Only two relay sizes provide a wide application range of 0.5 to 400 A. Digital slide switches provide very precise setting of both the motor full load amps and desired trip time.
Other Catalogs (From Rockwell Automation, Inc.) :
