The VS-3 power supply is a very convenient portable, non-isolated “variable source” from 0 volts to 150 Vac or 0 volts to 150 Vdc and rated for up to 3 amps, thus the name VS-3. It is comprised of an illuminated voltmeter that reads to the first significant digit, AC variable system output voltage, DC variable system output voltage, logic output voltage and one sense (continuity) contact monitoring points. Banana jacks for connection of test leads are spaced at intervals that allow the use of dual banana test plugs if desired. The VS-3 is protected by two levels of overcurrent protection; AC input, and ground fault protection by a GFCI. All circuitry is housed inside a custom designed case made from 16 gauge steel. An Internal fan dissipates heat buildup and exhaust through louvered side vents built into the case. The carrying handle is designed with a “spring return to rest” position and is padded for comfort. The case has been sized for optimum portability and is balanced from the handle during transportation. The case has a powder coated finish that is scratch, chemical and weather resistant. Rubber padded feet support the case when in the upright position and a convenience receptacle is located on the side of the case. A unique feature of the VS-3 is that it contains “Magnet Packs” on the back of the case. These “Magnet Packs” can support the VS-3 and allow it to “hang” from any magnetic metal surface. The VS-3 can be powered by our UPS system, eliminating the need for an extension cord. The ability to magnetically attach the VS-3 near the source of connection and eliminating the need for an extension cord makes the VS-3 a “must have tool” for technicians.