The Delta DTR007S21A is a single‑phase input (5 A) to three‑phase output inverter drive rated at 0.9 kVA (3.2 A per phase). Common failure points on this model include overheating of the internal MOSFET array, degradation of the gate driver ICs, and failure of the DC link capacitors due to voltage spikes or poor heat sinking. Begin troubleshooting by verifying that the input supply is within 200‑240 V and that the output phases are correctly phased; then check the MOSFET die temperatures with an infrared thermometer and inspect the DC link capacitor ESR for excessive leakage. Finally, review any diagnostic LEDs or fault codes on the drive’s status panel to pinpoint component faults.[oss-gpt-20b]