Fault Phenomenon: Komatsu 830E-5 mining truck inverter reports low coolant level or insulation fault, water stains at the bottom of the cabinet.

Troubleshooting Process:
– Checked hoses: cooling hoses aged and cracked or fittings loose.
– Checked water pump: water pump seal failed, leaking.
– Checked radiator: radiator core corroded and perforated.
– Checked coolant: coolant contained impurities, corroding lines.

Root Cause: Rubber hoses in the inverter water cooling system aged and cracked due to long-term high temperature, causing coolant to leak onto electrical components.

Required Parts: Replace all aged cooling hoses and add specialized coolant.