FANUC Alarm SRVO-201 — SERVO Panel E-stop or SVEMG abnormal
Error- Hardware
- emergency stop and dual safety chains
- Controllers
- R-J3iB / R-30iA
- FANUC class
- SERVO
- Hardware family
- FANUC emergency stop, pendant and dual safety chain alarms
FANUC SRVO-201 (“SERVO Panel E-stop or SVEMG abnormal”): The operator panel emergency stop push button is pressed and miswiring on SVEMG is detected. First check: Check the wiring of SVEMG.
Updated 2026-10-22 · LogrobotLM reference
Description
The operator panel emergency stop push button is pressed and miswiring on SVEMG is detected. Or the operator panel emergency stop push button is pressed slowly so that SVEMG signal is delayed.
Remedy
Check the wiring of SVEMG. If the wiring of SVEMG is not connected, correct the wiring of SVEMG. If the wiring has no problem, twist the operator panel emergency stop push button clockwise to release. Press RESET. Refer to the maintenance manual for details.
Field diagnosis
A press on the operator panel E-stop button was detected, yet the hardware stop chain remains closed: the contact and the stop line tell two different stories.
What to check
- Release the button and reset.
- If the code returns on every press, the emergency stop board or the panel board no longer sees one of the two channels: diagnose before continuing.
- A very slow press on the button can also produce the code, without any fault.
- Note: Non-latched variant of SRVO-277: 277 requires a power cycle to clear.
Related codes
Indicative field information — the robot manufacturer's manual and safety procedures always prevail. Never bypass a safety device; apply lockout/tagout (LOTO) before any physical intervention. How this reference is built →