4. SAFETY OBSERVATION FUNCTION
4.4.5 Position feedback fixing diagnosis function
(1) Summary
The position feedback fixing diagnosis function generates [AL. 79.8 Position feedback fixing error] to
make the amplifier STO state when position data from the encoder is fixed.
(2) Operation summary
The position feedback fixing diagnosis function will be enabled when the safety observation function is
enabled and moreover the amplifier is not STO state. When a position feedback does not change for the
time set with [Pr. PSA22 Position feedback fixing error detection time], [AL. 79.8 Position feedback fixing
error] occurs and the STO function operates.
Position (P)
ON (no alarm)
ALM (Malfunction)
OFF (alarm)
ON (disabled)
STOS (STO output)
OFF (enabled)
4 - 20
Rotation
Stop
[Pr. PSA22]
Position change: 0 pulse
STO status
Servo motor
position