Safety Circuit Fault

What does E.SAF mean?

The inverter output has been shut off due to a detected fault in the safety circuit or a functional safety-related issue. This can be caused by a broken wire in the safety input terminals (S1, S2, PC) when using safety functions, or general functional safety failures in Safety Communication models. This critical fault ensures machinery cannot operate unsafely.

• Open circuit or damaged wiring between the external safety device and inverter safety input terminals (S1, S2, or PC).
• Failure of external safety relay contacts or safety device outputs to close or open correctly.
• Short circuit between safety input terminals (S1, S2, or PC) and ground, or between the terminals themselves.
• Incorrect configuration of internal safety parameters or discrepancies between safety function settings (e.g., STO, SS1).
• Internal hardware fault on the inverter's control board related to the safety input monitoring circuit.

Click steps to track your progress.

1. 1

   1. Measure continuity of wiring from external safety device output to inverter terminals S1, S2, and PC (expected: < 1 Ohm when active).

2. 2

   2. Verify the operating status of the external safety relay by checking its output contacts (e.g., using a multimeter, expected: 24VDC when enabled).

3. 3

   3. Check for short circuits between terminals S1 and PC, S2 and PC, and S1/S2/PC to ground using a multimeter (expected: infinite resistance).

4. 4

   4. Review inverter parameters related to safety functions (e.g., Pr.1044 STO enable, Pr.1045 SS1 function) for correct configuration.

5. 5

   5. Temporarily bypass the external safety circuit with a jumper wire between S1, S2, and PC (if permissible by safety procedures) to isolate the fault source.