02.91.020-CE07 by KEB

The 02.91.020-CE07 is a rectifier module manufactured by KEB for the COMBITRON Rectifiers series. It is used in control cabinets to convert alternating source power into direct current for brake coils and auxiliary loads found in small drives and handling units. Installed on the secondary side of a control transformer, the module provides a stable DC supply without requiring a separate power stage. That arrangement is common where electromagnetic brakes must release reliably as soon as the control circuit is energized, and the compact enclosure fits easily alongside signal devices in standard automation cabinets.

This model uses a full-wave bridge so the DC output receives current on both half cycles, which reduces ripple compared with half-wave designs. Line compatibility extends to CE 275 VAC - UL 240 VAC, covering common 230 V and 240 V control voltages used in different regions. The terminal arrangement is marked AC/DC, showing that the input terminals accept AC while the output terminals provide rectified DC. At a cabinet temperature of 45 °C, the unit can supply 2.0 A, which is suitable for typical spring-applied motor brakes. The enclosure is rated IP20, so live parts are finger-safe, but the module should be kept away from liquids and conductive dust.

The housing measures 37×25×17 mm, allowing installation on tightly packed DIN rail assemblies. Wiring accepts conductors up to 1.5 mm², and each screw terminal should be tightened to 0.5 Nm to maintain a low-resistance connection during vibration. Correct terminal torque also helps prevent intermittent voltage drop during repeated machine movement. When the ambient temperature rises to 80 °C, continuous output is limited to 1.0 A to prevent excessive junction heating. Climatic category 3K3 indicates suitability for ventilated control rooms that are not air-conditioned, and the stated maximum ambient temperature sets the upper operating limit for the module.