VT-NE31-18

The VT-NE31-18 is a compact bipolar power supply unit produced by Bosch Rexroth Indramat within the VT-NE Power Supply Units series. Designed for control cabinets, it delivers symmetrical DC rails needed by analog amplifier cards, sensors, and small actuator stages in industrial automation. The module installs on an EN 60715 top-hat rail and occupies minimal depth and width, allowing dense placement of auxiliary electronics within the cabinet.

It accepts an input range of 230/115 VAC ±10%, so the same unit can be wired to European or North American mains without a selector switch. The internal transformer and rectifier operate at nominal mains frequencies of 50/60 Hz, ensuring correct magnetizing current under either grid standard. At full load, the first regulator provides +24 VDC, and the second channel supplies -24 VDC; both rails are actively filtered to reduce conducted noise affecting adjacent servo drives. The shared output stage is rated for a maximum continuous current of 0.25 A, which covers typical demand from proportional valve electronics and low-power relay boards.

Protection is provided by a 0.8 A slow-blow fuse on the primary side, limiting inrush and fault currents before cabinet circuit breakers trip. Under a balanced load, each rail can deliver 6 W, keeping component temperatures below rated limits while supporting small-signal circuitry. Residual ripple measured at the terminals remains less than 5%, so precision analog stages do not require additional decoupling capacitors. Field wiring with conductor sizes up to 4 mm² can be connected to the screw clamps. The enclosure has a mass of 1.1 kg, allowing standard DIN-rail clips to support the unit without additional brackets. Its dimensions are 84 mm wide, 70 mm deep, and 119.5 mm high, providing clearance around the ventilation slots when installed alongside compatible cabinet components.