Input phase loss protection
Mitsubishi · D700 Inverter
What does E.ILF mean?
This fault signifies a loss of one or more phases (R/L1, S/L2, T/L3) on the inverter's input power supply. This protection, which can be enabled by Pr. 872, stops the inverter to prevent damage to its internal converter section and DC bus capacitors. Continuous operation with an input phase loss can drastically shorten the inverter's lifespan. It may also trip due to large unbalanced phase voltages or if the load on the inverter is very light.
Complete Troubleshooting Guide
- 1
Check the incoming three-phase power supply for voltage presence on all phases (R/L1, S/L2, T/L3) using a multimeter.
- 2
Inspect all power connections between the main power supply (breaker, contactor) and the inverter input terminals for loose or broken wires.
- 3
Measure the phase-to-phase voltages of the input power supply to check for significant voltage unbalance.
- 4
Verify that Pr. 872 (Input phase loss protection selection) is set to '1' to enable this protective function.