The Velonex Model 587 is a voltage‑ and current‑surge generator designed to produce ANSI/IEEE C62.41 waveforms (6 kV amplitude, up to 500 A) for low‑voltage AC line testing. Common failure modes include degraded output due to capacitor aging or leakage in the surge network, malfunctioning trigger input circuitry (2.5–10 V pulse), and distortion of the oscillatory waveform from worn transformer windings or faulty rectifier diodes. First‑check diagnostics should verify the power supply voltage and ripple, inspect the trigger input for proper signal integrity, and perform a visual inspection of the surge network and output capacitors for signs of bulging or leakage. Additionally, run a baseline waveform test to confirm compliance with C62.41 specifications before proceeding with component replacement.[oss-gpt-20b]