Calculating Charge Time; Power-Up Idle Time Limit; Testing After Charging; Using The Alternator Performance Tester - Schumacher XC75 Owner's Manual

6 Volt Battery
Voltage Reading
Less than 6.1
Tester and Charger: When first turned on, the unit operates only as a tester, not as a
charger. Selecting a charge rate activates the battery charger and deactivates the tester.
Pressing the CHARGE RATE 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 10 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.
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 CHARGE RATE switch until all charge rate LED's are off.
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 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. 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, have
the charging system checked by a qualified technician.
12.

CALCULATING CHARGE TIME

Find your battery's rating on the chart below, and note the charge time given for each
charger setting. The times given are for batteries with a 50% charge prior to recharging.
Add more time for severely discharged batteries.
NR means that the charger setting is NOT RECOMMENDED.
BATTERY SIZE/RATING
Motorcycle,
SMALL
BATTERIES
tractor, etc.
200 - 315 CCA
CARS/ 315 - 550 CCA
TRUCKS
550 - 1000
MARINE/DEEP CYCLE
Voltage Reading
6.4 or More
6.1 to 6.3
6 - 12 AH
garden,
12 - 32 AH
40 - 60 RC
60 - 85 RC
80 - 190 RC
CCA
80 RC
140 RC
160 RC
180 RC
12 Volt Battery
12.8 or More
12.2 to 12.7
Less than 12.2
XC75
CHARGE RATE/CHARGING TIME
3 AMP
1¼ - 2½ hrs
2½ - 6¾ hrs
7½ - 9½ hrs
9½ - 12¼ hrs
12¼ - 23¼ hrs
11¾ hrs
18 hrs
20 hrs
22 hrs
8
• •
Battery Condition
Charged
Needs Charging
Discharged
5 AMP
¾ - 1½ hrs
1½ - 4 hrs
4½ - 5¾ hrs
5¾ - 7½ hrs
7½ - 14 hrs
7 hrs
10¾ hrs
12 hrs
13¼ hrs
10 - 20 AMP
NR
NR
1¼ - 3 hrs
1½ - 3¾ hrs
1¾ - 7 hrs
1¾ - 3½ hrs
2¾ - 5½ hrs
3 - 6 hrs
3½ - 6¾ hrs