Troubleshooting: measuring the power output between 70-110V change, disconnect the line output circuit, access dummy load. Power light bulbs, measuring 110V voltage is normal, indicating that the power supply is normal. Turn off the power to the circuit with a multimeter to measure resistance profile line pipe collector-to-ground resistance, normal, indicating that part of the line-to-ground no DC output short circuit, but access to the lower supply voltage 110V, AC should be shorted. At this point we leave the welding under load, access lines, disconnect line drive, and then power. Surveyors tube collector 110V back to normal, the line AC 110V line pulse when a short circuit is not normal, suspected line output transformer damaged, replace the power supply everything is normal.
Fault Summary: line output transformer is relatively easy to faulty component appears, it appears in addition to the exchange of internal short circuit between turns, but also prone to some obvious faults, may also open an internal coil or two coils shorted, no acceleration voltage fault, all must be replaced.