Mains failure

What does #36 mean?

A power shortage or interruption occurred in the main power supply while the compressor was running, leading to an unexpected loss of power to the unit. This can result in system disruption, unexpected shutdowns, and potential data loss if not properly addressed. It prevents consistent operation of the unit.

• Loss of one or more phases (e.g., L1, L2, L3) from the incoming utility power supply to the equipment.
• Blown fuse (e.g., F1, F2, F3) or tripped circuit breaker (e.g., CB1) on the main input power line to the unit.
• Loose or corroded connections at the main power input terminals (e.g., R, S, T) of the control panel or drive.
• Faulty input rectifier bridge or DC bus capacitors within the drive, leading to an inability to maintain DC link voltage during transients.
• Supply voltage sag below the minimum operating threshold (e.g., 340V AC) during heavy load demands on the upstream electrical network.

Click steps to track your progress.

1. 1

   Measure the incoming line voltage (e.g., L1-L2, L2-L3, L3-L1) at the main disconnect switch (e.g., QF1) using a multimeter.

2. 2

   Check the continuity of all input fuses (e.g., F1, F2, F3) or verify the tripped status of main circuit breakers (e.g., CB1) visually.

3. 3

   Inspect all main power connections from the incoming supply to the drive input terminals for tightness and signs of overheating or arcing.

4. 4

   Verify that the main power supply contactor (e.g., K1) is correctly engaged and its auxiliary contacts provide proper feedback to the control system.

5. 5

   Check drive parameter P1-10 (Minimum Input Voltage Trip) to ensure it is set appropriately for the nominal supply voltage and tolerance.