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Battery Load Test

CAUTION: Wear a safety face shield when load testing a battery to prevent possible personal injury.

TOOLS REQUIRED
J 39200 Digital Multimeter

IMPORTANT: Do not load test a frozen battery.




1. Connect a J 39200 and a battery load tester (2) across the battery terminals.
2. Apply a 300 ampere load for 15 seconds to remove the surface charge from the battery (1).
3. Remove the load and wait 15 seconds to let the battery recover.
4. Apply 250 amperes to the battery.
5. Measure the battery voltage after 15 seconds.
6. Remove the load.
7. If the voltage does not drop below the minimum voltage listed below, the battery is good and should be returned to service. (The battery temperature must be estimated by feel and by the temperature the battery had been exposed to for the preceding few hours).
8. If the voltage drops below the minimum listed below, replace the battery.

BATTERY LOAD TEST VOLTAGE

Estimated Temperature Minimum Voltage
21°C (70°F) 9.6 VDC
10°C (50°F) 9.4 VDC
0°C (30°F) 9.1 VDC
-10°C (15°F) 8.8 VDC
18°C (0°F) 8.5 VDC
Below -18°C (0°F) 8.0 VDC