Schumacher SC-8020A - Manual (Page 14)

• 12 •
The CHARGED (green) LED will light if a charged battery is tested. •
The CHARGING LED does not light in the battery test mode. •
The • CONNECTED LED lights when a properly connected battery is de-
tected.
When the tester digital display is set to
• VOLTAGE, the CHARGED and
CHARGING LEDs won’t light (it could be testing a battery or an alterna-
tor).
iNiTiAL pERCENT CALCULATiON 14.7
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.
NOTES FOR TESTiNg BATTERy %
14.8
A recently charged battery could have a temporarily high voltage due
to what is known as “surface charge.” The voltage of such a battery will
gradually drop during the period immediately after the charging system is
disengaged. Consequently, the tester could display inconsistent values for
such a battery. For a more accurate reading, the surface charge should be
removed by temporarily creating a load on the battery, such as by turning
on lights or other accessories.
The battery % ranges from 0 to 100.
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 BUiLT-iN ALTERNATOR TESTER 15.
This battery charger has a built-in alternator tester that displays either
an accurate alternator voltage or an estimate of the alternator’s relative
output compared to normal alternators. The Alternator % values displayed
should be taken as general reference, not precise diagnosis. The alterna-
tor tester functions the same as the battery tester (see previous section of
this manual for details) with a few differences.
TESTiNg SEqUENCE
15.1
There are three basic steps required to use the SC-8020A as an alternator
tester.
1. Connect the battery clamps (see sections 6 and 7).
2. Connect the charger power cord to a 120V AC wall outlet (see section 8).
3. Start the vehicle and turn on the vehicle’s headlights. Read the voltage
on the digital display or press the DIGITAL DISPLAy button to set the
tester to ALTERNATOR % and read the alternator percent.
TESTER STATUS LEDs 15.2
When the SC-8020A is operating as an alternator tester, the status LEDs