Chapter 4: Maintenance; Battery - Global Water GL400 User Manual

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.
GL400-1-1
Sample Period Theoretical
Battery Life
1 second 88 hours
1 minute 65 days
30 minutes 478 days
1 hour 536 days
1 day 607 days
Checking the battery requires the GL400 en-
closure be opened.
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).
*See Recording Interval and Memory Management, pages 28 – 30
Global Water ● (800)876-1172 ● www.globalw.com
Recommended Time Between
Battery Check
72 hours
2 months
6 months
6 months
6 months
GL400-7-1
Sample Period Theoretical
Battery Life
1 second 15 hours
1 minute 12 days
30 minutes 234 days
1 hour 338 days
1 day 591 days
remove connectors
Maintenance
4
Recommended Time Between
Battery Check
12 hours
1 week
6 months
6 months
6 months
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