VT-NE31-12

The VT-NE31-12 is a compact bipolar power supply unit built by Bosch Rexroth Indramat for the VT-NE Power Supply Units series. As a dedicated auxiliary source, it provides isolated positive and negative rails for analog amplifier cards, valve drivers, and sensor loops in industrial automation cabinets. Its compact, dual-output design mounts directly on a top-hat rail, allowing straightforward integration with other DIN-mounted control hardware.

The module accepts a mains input of 115/230 VAC with a tolerance of ±10% and operates at 50/60 Hz. The terminals accommodate conductors with a cross-sectional area of up to 4 mm², and an internal LED indicates the presence of stabilized output power. Under full load, channel 1 supplies +24 VDC, while channel 2 supplies -24 VDC. Each rail provides up to 6 W through the filtered dual-output configuration required by low-noise electronics. The maximum continuous output current is 0.25 A, which helps control the module’s thermal rise during continuous operation. Residual ripple is less than 5%, reducing the need for additional smoothing capacitors in downstream precision devices. The input selector is initially set to 230 VAC, and spring clips secure the unit to an EN 60715 top-hat rail.

Primary-side circuit protection is provided by a 0.8 A slow-blow fuse, while supplementary miniature fuses protect both DC rails against short circuits. When the supply is unloaded, its output can rise to ±27 VDC, which remains within the accepted input range of typical servo control cards and can be considered during system diagnostics. The electronics are installed in a ventilated enclosure weighing 1.1 kg, helping limit the load placed on the mounting rail and cabinet structure. The unit is Series 12 and uses screw-clamp terminals that accept the supported conductor range without adapters.