BatteryMINDer 28252-AA-Series - Manual (Page 11)

Rev. I-100511 Page 11 P/N VDC28252-AA-Series-MNL
BatteryMINDer ® Model 28252-AA-Series
TESTING A SEALED, AGM
LEAD ACID BATTERY
These batteries have no filler caps or manifold-type covers. Because you
cannot gain access to the interior of your battery you cannot test it with a
hydrometer.
USE A DIGITAL VOLTMETER ONLY:
1. Recharge the battery with the BatteryMINDer to ensure it is as
completely charged as possible, before you determine its condition. Allow
battery to “rest” (see pg. 9) overnight before testing with a digital voltmeter
only.
Failure to test a “rested” (see pg. 9) battery will cause false readings. Be
certain to read and understand all safety related instructions (pages 3 to
7) before proceeding further.
2. Measure battery’s voltage, without any load attached. If the voltage
is less than 25.2 volts (Typically 75% of charge) the battery may be too
heavily sulfated to be fully recoverable. If voltage is 25.2-V or higher
recovery can be expected, given sufficient time.
3. Press desulfation button to start process of dissolving sulfate crystals.
Ensure battery is removed from aircraft prior to desulfation. Continue
in this mode for 72 hours. Stop process by pressing desulfation button.
Test battery voltage and compare to table 2 below. If voltage is not in the
full capacity range restart the desulfation process and continue for an
additional 72 hours before retesting. Continue repeating this procedure
until no further increase in battery voltage is observed.
Note: Do not expect to completely dissolve sulfate in a day. Long
established sulfate will require a longer period to be fully dissolved. Be
patient and you will be rewarded with a “sulfate-free” battery. If not
seriously damaged by sulfate, battery has a very good chance of meeting
80% Cap (Airworthy) Test.
OCV - “Rested”
Voltage
Full Capacity
Percentage
25.8 - 26.2 Volts 100%
25.2 - 25.8 Volts 75%
24.8 - 25.2 Volts 50%
24.4 - 24.8 Volts 25%
24.0 - 24.4 Volts 0%
<22 Volts
= shorted
OCV=Open Circuit
No Load Voltage
TABLE 2