Maintenance And Care - Napa 90-620 Owner's Manual

TESTER AND CHARGER
When first turned on, the unit operates only as a tester, not as a charger. Selecting a charge rate or waiting
30 seconds (see Power-Up Auto-Start above) activates the battery charger and deactivates the tester.
Pressing the Rate Selection button when charging (indicated by the Charging LED lit) will stop charging and
activate the tester.
USING THE BATTERY VOLTAGE TESTER
1. With the charger unplugged from the AC outlet, connect the charger to the battery, following the
instructions given in previous sections.
2. Plug the charger AC power cord into the AC outlet.
3. Press the Battery Type button until the correct type is indicated.
4. Read the voltage on the digital display. Keep in mind that this reading is only a battery voltage reading;
a false surface charge may mislead you. Compare the reading to the following chart.
6V Battery
Voltage Reading
6.4 or more
6.1 to 6.3
Less than 6.1
TESTING AFTER CHARGING
After the unit has been changed from tester to charger (by selecting a desired rate), it remains a charger.
To change the battery charger back to a tester, press the Rate Selection button.
NOTE: The battery tester is only designed to test batteries. Testing a device with a rapidly changing
voltage could yield unexpected or inaccurate results.
USING THE ALTERNATOR PERFORMANCE TESTER
1. With the charger unplugged from the AC outlet, connect the charger to the battery, following the
instructions given in previous sections.
2. Plug the charger AC power cord into the AC outlet.
3. Use the Rate Selection button to select 6<>2A. After the Charging (yellow/orange) lights, press the
Rate Selection button again to put the charger in tester mode and avoid the 30 second auto start.
4. Start the vehicle, rev the engine at 2000 rpm for 30 seconds and turn on the vehicle's headlights or
other accessories.
5. Read the voltage on the digital display. If you get a reading between 13.4 volts and 14.6 volts, the
alternator is working properly. If the reading is less than 13.4 volts or more than 14.6 volts, refer to
your vehicle's manual or have the charging system checked by a qualified technician.

12. MAINTENANCE AND CARE

A minimal amount of care can keep your battery charger working properly for years.
• Clean the clamps each time you are finished charging. Wipe off any battery fluid that may have come
in contact with the clamps to prevent corrosion.
• Occasionally cleaning the case of the charger with a soft cloth will keep the finish shiny and help
prevent corrosion.
• Coil the input and output cords neatly when storing the charger. This will help prevent accidental damage
to the cords and charger.
• Store the charger unplugged from the AC power outlet in an upright position.
• Store inside, in a cool, dry place. Do not store the clamps clipped together, on or around metal, or
clipped to the cables.
12V Battery
Voltage Reading
12.8 or more
12.2 to 12.7
Less than 12.2
Battery
Condition
Charged
Needs charging
Discharged
• 7 •