Liebert 1500 - Manual (Page 45)

Maintenance 39
5.2 Troubleshooting
Table 39 provides a list of the problems that may occur on the Helios DC System 4000/48, along
with their possible causes. Blown fuses and tripped circuit breakers should always be investi-
gated before utilizing Table 39.
Table 39 Fault diagnosis
Fault symptom Possible causes
No DC output current Open AC circuit breaker
Open DC circuit breaker
Faulty connection between the power shelf and the rectifier (Helios
Rectifier 100/48)
Faulty connection between the rectifier and the power plant
Sense leads opened
Incorrect indication of the DC
output current Incorrect meter calibration
Loose shunt leads connection
Low float voltage Faulty rectifier(s)
Shorted battery cell(s)
Prolonged power failure
Incorrect float voltage adjustment
Sense leads opened
Low recharge voltage Incorrect float voltage adjustment
Discharge load greater than the rectifier’s capacity (batteries are
recharging or the system is in manual bypass)
Sense leads opened
High float or recharge voltage Faulty rectifier(s)
Incorrect Float/Equalize adjustment
Failure to generate alarms
during alarm conditions Incorrect connections between the controller and the rectifiers and
distribution panels
Failure to generate cabinet
alarm during minor or major
alarm conditions Faulty LP fuse on the controller (F31)
Faulty cabinet alarm lamp
Faulty or loose connection
Failure to generate RFA alarm
under appropriate conditions Faulty rectifier
Faulty wiring
Faulty RFA LED
Failure to generate FA alarm Faulty wiring
Faulty fuse
Faulty FA LED
Loose connection
HV lamp lit High discharge voltage condition
Incorrect HV level adjustment
LV lamp lit Low discharge voltage condition
Incorrect LV level adjustment
HF lamp lit High discharge voltage condition
Incorrect HF level adjustment
LF lamp lit Low discharge voltage condition
Incorrect LF level adjustment
FA lamp lit Blown fuse or extended FA alarm
CFA lamp lit Blown charge fuse
DFA lamp lit Blown distribution fuse
RECT MIN lamp lit One rectifier has failed
RECT MAJ lamp lit Two or more rectifiers have failed
RECT FAN lamp lit Defective rectifier fan(s)