Always
O
n UPS Systems
M0704_NX_Series_Service_Manual V2.17 2012-06-12
56
Table 19.1
LED Operation for the 3A PCB
PCB FUNCTION LOCATION
NORMAL ABNORMAL
SOLUTION
PCB LED
LED
Illuminated
Description
LED
Illuminated
Description
3A Main Control PCB Module
LED A1
No
3T (R phase
working)
Yes
R phase failure
and UPS
shutdown
Check 3T (R phase) ensure cable connections
are secure and correctly attached.
Replace the board
LED A2
No
3S (S phase
working)
Yes
S phase failure
and UPS
shutdown
Check 3T (S phase) ensuring cable
connections are secure and correctly attached.
Replace the board
LED A3
No
3T (T phase
working)
Yes
T phase failure
and UPS
shutdown
Check 3T (T phase) ensuring cable
connections are secure and correctly attached.
Replace the board
LED A4
No
3G working
Yes
3G has problem
Check 3G and ensure cable connections are
secure and correctly attached.
Replace the board
LED A5,
A6
All Yes
PCB has power
All No
PCB has no input
power
Check 3B and ensure cable connections are
secure and correctly attached.
Replace the board