ABB AC31 Assembly And Operation Manual page 109

1.5.4.2.1 LED display
The LED display on the replacement device is changed:
Fig. 68: AO523
No.
1
2
3
4
2018/09/24
Display of module
8 yellow LEDs to indicate the signal status of the analog inputs (X2 and X3)
8 yellow LEDs to indicate the signal status of the analog inputs (X6 and X7)
2 red LEDs to indicate errors (of AO523 module)
1 green LED to indicate the status of the supply voltage of the AO523 module (is
supplied via X4)
The replacement device does not provide a test button to measure functionality.
3ADR010122, 8, en_US
Replacement devices: I/O modules > Replacement device 07AC91-AD
AC31 Adapters
109