ABB PCS100 UPS-I - Page 63

PCS100 UPS-I User Manual 63
LED 6
No SCR short
Indicates that no UD SCR is shorted, or stack is not bypassed
(e.g., FSB closed). Led 6 is off when there is a very low voltage
across an SCR.
Note:
This LED indicates a shorted SCR by detecting a lower-than-
expected voltage across the SCR. This condition also occurs
when an FSB or external Bypass is closed, or if load current is
very low or zero. Indication is meaningful when in online mode
with >10% load current.)
LED 3
Open FSB
Command exists from the master to open the FSB. This will
occur when the PCS100 UPS-I is Online and there are no faults.
LED 7
FSB Open
The FSB is open (feedback from the ACB aux contacts)
Table 7-11: Utility Disconnect Status LEDs