EF7
External Fault
Yaskawa · Drive Fault Codes
What does EF7 mean?
An external fault detected by the drive, signaling an issue with a device connected to the external fault input terminals, specifically S1. The fault code (EF0-EF8) may indicate different external fault conditions defined by the user or manufacturer.
Common Causes
- Fault condition from an external safety device (e.g., thermal overload, emergency stop switch, limit switch)
- Incorrect wiring or loose connection to the S1 terminal, leading to an unintended fault signal
- Faulty external sensor or switch providing the fault signal to the drive.
Repair Steps & Checklist
Click steps to track your progress.
- 1
Inspect all external devices connected to the S1 terminal for their operational status and reset any tripped devices.
- 2
Verify the integrity of wiring connections to the S1 terminal and check for continuity.
- 3
Measure the voltage signal at the S1 terminal to ensure it is within the expected range (e.g., 24VDC when the fault is clear).
Verified technical data. Last updated: March 2026
Related Faults
Source: Yaskawa Drive Fault Codes