Schumacher PSC-12500A Proseries Owner's Manual page 8

3. If necessary, press the BATTERY TYPE button until the correct type is indicated.
4. Read the voltage on the digital display or press the Display Mode button to set the
tester to BATTERY % to read the voltage as a percent of charge.
Tester and Charger: When first turned on, the unit operates only as a tester, not as a
charger. To continue to use it only as a tester, avoid pressing the BATTERY SIZE button.
Selecting a charge rate activates the battery charger and deactivates the tester. Pressing
the BATTERY SIZE button when the ENGINE START LED is lit (except during the 180
second cool down) will shut off the charger and activate the tester.
Power-Up Idle Time Limit: If no button is pressed within 15 minutes after the battery
charger is first powered up, the charger will automatically switch from tester to charger if a
battery is connected. In that case, the charger will be set to the start up default settings.
Tester without Time Limit: If either the DISPLAY MODE or BATTERY TYPE button is
pressed within the first 10 minutes after the battery charger is powered up, the unit will
remain a tester (not a charger) indefinitely, unless a charge rate is selected.
Testing After Charging: After the unit has been changed from tester to charger (by
selecting a charge rate), it remains a charger. To change the battery charger back to a
tester, press the BATTERY SIZE button until all charge rate LEDs are off.
Tester Status LEDs: When the unit is operating as a battery tester, the status LEDs light
under the following conditions:
• The CHARGED (green) LED will light if a charged battery is tested.
• The CHARGING (yellow) LED does not light in the Battery Test Mode.
• The CONNECTED (yellow) LED will light if a properly connected battery is detected.
Initial Percent Calculation: When a battery % is calculated for the first time after
connecting a battery, the digital display will show three dashes ("---") for a period as long
as several seconds while the tester analyzes the battery.
Using the Alternator Performance Tester
Overview
This battery charger has a built-in alternator tester that displays an estimate of the alternator's
relative output compared to normal alternators. The alternator % values displayed should be
taken as a general reference, not a precise diagnosis. The alternator tester functions the same
as the built-in battery voltage tester (see previous section for details) with a few differences.
Testing Sequence: There are three basic steps required to operate this unit as an
alternator tester:
1. With the charger unplugged from the AC outlet, connect the charger to the battery
following the instructions given in Sections 6 and 7.
2. Plug the charger AC power cord into the AC outlet, following the instructions given in
Section 8.
3. Start the vehicle, and turn on the vehicle's headlights. Read the voltage on the digital
display or press the DISPLAY MODE button to set the tester to ALTERNATOR % to
read the voltage as a percent of charge.
Alternator Testing Note: The DISPLAY MODE cannot be set to ALTERNATOR %
during charging.
General Charging Notes
Fan: The charger is designed to control its cooling fan for efficient operation. It is normal
for the fan to start and stop when maintaining a fully charged battery. The fan does not run
in Tester Mode. Keep the area near the charger clear of obstructions to allow the fan to
operate efficiently.
Restart: If the Charge Mode is changed after charging has started (by pressing the
BATTERY SIZE or BATTERY TYPE button), the charging process will restart.
Voltage: The voltage displayed during charging is the charging voltage and is usually
higher than the battery's resting voltage.
Charging Tips
Read this entire manual before using your battery charger. The following tips serve only as
a guide for specific situations.
• If your vehicle won't start – It is not necessary to fully charge your battery to start
a vehicle. When the battery's charge is 77% or more, the battery has usually been
charged enough for the vehicle to start and operate normally. If operating the vehicle
continuously for an extended period (such as a long drive), the vehicle's charging
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