Fanuc Alarm AL-L FSSB Alarm Information by KFASLLC

KFAS: Fanuc CNC Parts, Service, & Repair

Fanuc ALARM AL-U aiSV-B

Alarm AL-U Fanuc 0iF or 31iB on aiSV-B means,
SV FSSB communication error (COP10A)
Cause and troubleshooting
(a) Replace the optical cable (COP10A) of the servo amplifier that is the furthest from the CNC of
those displaying L. (the cable between UNIT 2 and UNIT 3.)
(b) Replace the servo amplifier that is the furthest from the CNC of those displaying L. (UNIT 2.)
(c) Replace the servo amplifier on the COP10A side that is the furthest from the CNC of those
displaying L. (UNIT 3.)

A06B6240 aiSV-B B65515EN Maintenance Manual

*CAUTION: High Voltage present.
Note: Some Machine's electrical cabinet doors are equipped with "door interlock" that will cause the breaker to trip when the door is open.
See the machine's manual for information on how to bypass so that you can observe the alarm LED status

Fanuc CNC Alarm App for your smart phone