NATO SLAVE RECEPTACLE CHARGING PROCEDURES
This task is intended for use by standard military battery shops or units without access to chargers but with access
to the NATO slave receptacle cable and a vehicle capable of slave charging.
Connect charger to the NATO slave receptacle. Ensure cable clamps and contacts are tight and clean with
minimal corrosion to assure good connections. Ensure all current drawing devices are OFF i.e. lights,
electronic equipment etc.
If possible, use a constant voltage charger of newer technology, which may have multiple charge settings
and steps such as an Absorbed Glass Mat (AGM) setting. If charger has this switch setting select this switch
position. If voltage is adjustable the voltage should be set between 28.8 volts and 30.0 volts or 24 volt switch
setting selected and there should be at least 5 amp current per battery available for charging. Such settings
may give the operator the option of setting the charge voltage and current, to expedite charge time, and will
assure decreasing amperage output as the battery charges in Step 5.
Do not use the values listed in Step 3 for the vehicle's voltage regulator setting.
Consult appropriate Technical Manual (TM).
Before applying power to charger, select the charger setting for AGM. If the charger has adjustable voltage
output capabilities, adjust the voltage to 28.8 volts to 30.0 VDC.
If battery charger has no adjustments or switches (and is not a SMART Charger and output voltage is
> 30.0 VDC) the battery should be closely monitored every 15 minutes, during the first two hours of charge
process. If it shows signs of excessive heat when touching the exterior, gassing, leaking or swelling during
charge stage, charging should be stopped immediately. If charger is an older model and user is unsure as
to the output voltage of the charger, see (WP 0005) for testing procedure.
Charge batteries for 12 hours or longer (see Step 8). Weekend charging of 64 hours (Friday 1600 to
Monday 0800) can be performed, but it is best to have someone check the system at least once per day to
assure proper operation (no excessive gassing, leaking, proper voltage applied) and to determine whether
charge has been completed. Severely depleted batteries (OCV < 10 VDC) can take up to four days to
recharge. If Open Circuit Voltage (OCV) is not significantly improved (> 10 VDC) after four days it may never
make a full recharge.
Immediately remove any battery from charger that shows signs of excessive heating, gassing, leaking,
or swelling during charge stage. Battery should be disposed of. Battery should be marked with a permanent
marker with date and statement "CHARGED, TESTED BAD"; then processed for disposal.