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Global Water
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4
Maintenance
Battery
Global Water recommends that the battery voltage be physically checked based on your recording interval*.
Refer to the following table.
Note, that the GL400 uses 160µA while “sleeping” and 10mA plus the signal current while taking readings.
This table is based on the worst-case scenario where all sensors are providing the maximum signal of
20mA.
Temperature can also affect battery life. A GL400 in an environment that has a sustained temperature of
23° C will run 5% longer than a unit that has a sustained temperature of 0° C.
*See
Recording Interval and Memory Management
, pages 28 – 30
Checking the battery requires the GL400 en-
closure be opened.
remove connectors
Test the battery with a voltage meter. The datalogger will not work reliably if the battery voltage is below
10V. If the battery is allowed to drain below 9V it may not charge back to 12V when the charger is applied.
The battery can be recharged using the included transformer, see Appendix D for charging instructions. If
the battery needs to be replaced, use a 12V, 2 AH lead acid gel cell for reliable service. Insert the battery
into the battery slot and reattach the battery connectors to terminals (blue connector to black terminal first
and red connector to red terminal second).
GL400-1-1
Sample Period
Theoretical
Battery Life
Recommended Time Between
Battery Check
1 second
88 hours
72 hours
1 minute
65 days
2 months
30 minutes
478 days
6 months
1 hour
536 days
6 months
1 day
607 days
6 months
GL400-7-1
Sample Period
Theoretical
Battery Life
Recommended Time Between
Battery Check
1 second
15 hours
12 hours
1 minute
12 days
1 week
30 minutes
234 days
6 months
1 hour
338 days
6 months
1 day
591 days
6 months
Maintenance
