4 check battery charger voltage, 5 check battery terminals and connecting wires, 6 check output voltage – Alpha Technologies GMX-915 User Manual
Page 52: 7 check output current, Check battery charger voltage, Check battery terminals and connecting wires, Check output voltage, Check output current

52
017-932-B0-002, Rev. B
6.0
GMX Power Supply Maintenance, continued
6.4 Check Battery Charger Voltage
The advanced three-stage charging features of the GMX Power Supply are completely self-
monitoring. During normal power supply operations, the power supply continuously verifies
the operating condition of the battery charger. If, for any reason, the battery charger fails, a
Charger Fail alarm displays on the Smart Display. No operator voltage checks are required.
6.5 Check Battery Terminals and Connecting Wires
Check each battery terminal and connection. Verify the posts are clean and the crimped
connectors are tight. Terminal connectors should be torqued in accordance with the battery
manufacturer's recommendation. If there is an in-line fuse in the battery cable, check the fuse
holder and fuse. Verify the terminals are properly protected with an approved battery terminal
corrosion inhibitor such as NCP-2. Record date of maintenance in the maintenance log.
6.6 Check Output Voltage
Measure the AC output voltage at the GMX Power Supply Transformer Module’s V
out
±
terminals (Output test points) using a true RMS AC voltmeter. Only use a True RMS meter, as
other meters may not give a correct reading.
Output voltages should appear within ±5% of rated output at a nominal line input.
Record the voltages in the maintenance log. Output voltages can also be observed by using
the Smart Display.
Whenever the battery breaker is turned off, or the batteries are not connected, the GMX Power Supply
automatically reports a No Batteries alarm. This is normal, and is a built in safety feature. The unit does not
attempt inverter operations, either standby or test, during a No Battery alarm.
NOTE:
Setting
Low (-5%)
High (+5%)
87Vac
82.65Vac
91.35Vac
63Vac
59.85Vac
66.15Vac
6.7 Check Output Current
With the GMX Power Supply in normal operating mode observe the Smart Display Output
Current. The value of output current will be dependent on the total amount of load connected
to the power supply. Record the current in the maintenance log.