04.91.020-CE07 by KEB

The 04.91.020-CE07 is a compact rectifier module manufactured by KEB for the COMBITRON Rectifiers series. It is installed on DIN rail or back-panel plates inside automation enclosures to change incoming alternating power into a controlled DC output that can energize motor brakes, electromagnetic clutches, or low-power logic circuits. By performing this conversion close to the load, the device helps reduce wiring length and isolate sensitive control electronics from higher-energy mains conductors. It is commonly used in machine-control panels that need a simple DC source for auxiliary functions without adding a larger power supply.

This module accepts supply networks operating at 50/60 Hz ±2% and withstands line potentials up to CE 500 VAC and UL 240 VAC. Inside, a full-wave rectifier circuit provides continuous output current of 2.0 A when the ambient cabinet temperature is held at 45 °C; the rating decreases to 1.0 A as temperatures rise, keeping the silicon junctions within their safe operating area. The device can switch both AC and DC loads, making it suitable for mixed-voltage panels. An enclosure rating of IP20 prevents accidental finger contact with live parts but still requires placement in a protected housing. Screw terminals accept solid or stranded conductors, and the specified tightening torque of 0.5 Nm helps maintain reliable clamping without damaging the threads.

The rectifier is intended for enclosed control spaces covered by climatic category 3K3. Electronics inside remain functional up to 80 °C, a temperature ceiling that matches the derating curve stated earlier. Mechanical dimensions of 46 mm in width, 28 mm in height, and 18 mm in depth support dense mounting next to contactors or miniature circuit breakers. These small proportions help airflow move around the unit so that heat from switching losses is removed efficiently, and they also leave room for adjacent terminal blocks or protective devices in narrow enclosures.