American Power Conversion DC Series user manual Fault Finding / Symptoms, Fault Symptoms

7 Fault Finding / Symptoms

The sub-system is designed for maximum reliability and therefore faults during normal operation are unlikely. If faulty operation does occur the source of the failure can usually be readily determined by inspection of the LED meter and the LED’s.

7.1 Warnings

POTENTIALLY LETHAL VOLTAGES AND SOURCES OF HIGH ENERGY ARE PRESENT WITHIN THE POWER SYSTEM. EXTREME CAUTION MUST BE OBSERVED AT ALL TIMES. ACCESS TO THE INTERIOR OF THE SYSTEM FOR INSTALLATION, COMMISSIONING, MAINTENANCE AND REMOVAL AND REPLACEMENT PURPOSES IS LIMITED TO FULLY TRAINED SERVICE PERSONNEL ONLY.

RINGS, WATCHES AND JEWELLERY SHOULD BE REMOVED AND ONLY SINGLE ENDED INSULATED TOOLS SHOULD BE USED WHEN WORKING OR MAKING MEASUREMENTS INSIDE THE SYSTEM. A SOLDERING IRON MUST NOT BE USED UNLESS THE INPUT, OUTPUT AND BATTERY (IF CONNECTED) HAVE FIRST BEEN ISOLATED.

7.2 Fault Symptoms

Typical fault symptoms and their possible causes are shown in table below. If the fault cannot be diagnosed contact the manufacturer.

SYMPTOM	POSSIBLE CAUSE(S)
Output voltage is zero at load	1. Failure of AC supply.
	2. Distribution device(s) tripped (check dist trip LED).
	3. Failure of external disconnect device.
All Rectifiers Input Healthy LED’s are lit (4 LED	1. Rectifiers have tripped due to over-voltage.
rectifiers) or Rectifier Fail LED not lit (single	2. System output not enabled, could be set to remote
LED Rectifier) but system bus voltage is zero	enable instead of local enable. (see section 2.5.4)
(LED display extinguished).
One or more rectifiers “output healthy” LED is	1. Rectifiers tripping due to over temperature condition,
extinguished temporarily (4 LED rectifiers). Or	(Local ambient may be above rated level). (see section
one or more “Rectifier Fail” LED lit temporarily	2.1.1)
(single LED Rectifier).
One or more rectifiers output healthy LED	1. System in overload condition (check current limit
extinguished (4 LED rectifiers). Or one or more	LED’s).
“Rectifier Fail” LED lit (single LED Rectifier).	2. System tripped due to over-voltage condition (check
	rectifier over-voltage LED’s).
Battery String not connected to system.	1. Battery connection switch set to “off”.
	2. Battery connection switch set to “auto” and battery
	string voltage below LVD level (see section 4.4.2)
	3. System output voltage is below low voltage reconnect
	level.
Battery string doesn’t disconnect when voltage	1. Battery disconnect switch set to “on” instead of “auto”
drops below LVD level.	(see section 4.4.2)

User Manual 990-9178A	Page 43 of 44	18th FEB 02
DC MX06 40A Shelf