Advertisement
Checking Open Circuit Voltage
OCV may be used to estimate the Lawn and Garden battery state-of-charge. Observe
the following guidelines:
Use a voltmeter that has been verified as accurate. An inaccurate meter
will give inaccurate results. The meter should read to the nearest 0.01
volts.
When checking OCV, the vehicle engine and all current drains must be
OFF. Any current flow into or out of the battery will cause an incorrect
voltage reading.
The battery must be stabilized before reading the OCV. If the battery has
been charged or used in a vehicle in the past 12 hours, remove the
surface charge (apply a 300amp load for 15 seconds). If the battery has
just been discharged, allow at least 15 seconds for the voltage to
stabilize, then read the OCV.
Use the following table to estimate the state-of-charge based on the
battery temperature:
*Estimates Only. Batteries vary +10% by model.
Keep batteries at 65% of full charge or higher. If the OCV falls below 12.4V,
recharge the battery.
IMPORTANT: When a battery needs charging, always charge it fully. If
you don't:
:
Stabilized
% Charge*
OCV (Volts)
at 0°C (32°F)
12.75
12.70
12.60
12.45
12.20
Retests with electronic testers may be inaccurate.
Full shelf life will not be available if returned to storage.
% Charge* at
25°C (75°F)
100%
100%
100%
90%
90%
75%
75%
65%
65%
45%
INSTRUCTION SHEET
Advertisement
