Elgar 1751SX is a single‑phase 1750 VA AC power source designed to drive non‑linear rectifier loads and support high crest factor testing up to 1 kHz. Common failure modes for this class of industrial power supplies include degraded output voltage regulation, overheating of the internal transformer or rectifier due to load spikes, and failure of the over‑current/over‑temperature protection circuitry. Begin troubleshooting by verifying that the input supply is within spec (55–65 VAC or 110–130 VAC), measuring the output voltage under no‑load and loaded conditions for stability, and inspecting the internal fuse, rectifier diodes, and cooling fan for signs of wear or damage.[oss-gpt-20b]