Superior Electric 15MG126 Powerstat Variable Autotransformer

The Superior Electric 15MG126 PowerSTAT Variable Autotransformer is a rugged, single‑phase voltage‑control device in the POWERSTAT 126 Series designed to accept 120 VAC line power and deliver a continuously adjustable output from 0 to 120 VAC. In the 126 Series, the unit provides a constant‑current rating of 15 A and a constant‑impedance rating up to 20 A at the 120 VAC line, yielding a nominal power class around 2 kVA (some listings identify this model as 2.1 kVA). The design features a carbon‑brush, low‑torque commutator system intended for long life and stable regulation, with negligible output voltage variation from no‑load to full‑load conditions when properly wired and loaded. 126 Series assemblies are offered in both enclosed and open configurations and can be configured as manual‑operated or motor‑driven units, supporting back‑of‑panel mounting in open types. The input frequency is suitable for 50/60 Hz service, making it versatile for laboratory benches, electronics test stations, and power‑supply experiments. Typical applications include building stable AC power test beds, motor control experiments, and electronics prototyping where a controllable, continuous voltage source is required. In practice, POWERSTAT units are commonly used to simulate AC conditions for testing equipment such as circuit breakers, watt‑hour meters, lighting ballasts, and household appliances, as well as for burn‑in and stability testing on experimental setups.