• 10 •
MAINTAIN MODE
When the green Charged/Maintaining LED is lit, the charger has started Maintain Mode. This mode of
operation is known as Float Mode Monitoring. In this mode, the charger keeps the battery fully charged by
delivering a small current, when necessary. The voltage is maintained at a level determined by the battery
type selected.
GENERAL CHARGING NOTES
• The board-mounted fans run, based on the corresponding board temperature or charging current level.
• If the charge mode is changed after charging has started (by pressing the Charge rate or Battery type button),
the charging process stops and begins again automatically at the new selection.
• The voltage displayed during charging is the charging voltage and usually will be higher than the
battery’s resting voltage.
• (DSR137) Use the 30A Service rate with a fully charged battery. This mode will prevent battery discharge
by providing up to 30A of current for ancillary functions during service or when idle in a showroom.
12. USING THE VOLTMETER TO TEST BATTERY STATE OF CHARGE
OVERVIEW
The charger has a built in voltmeter to test your battery’s state of charge. The charger does not have
a built in load tester. As such, 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 eventually 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 by turning on the lights or other accessories.
The battery tester is only designed to test 6V and 12V batteries. Testing a device with a rapidly changing
voltage could yield unexpected or inaccurate results.
TESTING SEQUENCE
There are three basic steps required to test the battery state of charge:
1. Connect the battery charger’s clips to the battery. Be sure to follow all of the precautions listed under
sections 6 and 7.
2. Connect the charger’s power cord to a 120 VAC outlet. Again, be sure to follow all of the precautions
listed under sections 6 and 7.
3. Press the Display Mode button and select the Voltage setting or % setting (DSR137). Read the
voltage or % shown on the digital display.
TESTER AND CHARGER (DSR137)
When first turned on, the charger begins as a tester until the START/STOP button is pressed or it auto
starts 30 seconds from being turned on, at which point it is a charger.
TESTING AFTER CHARGING
After the unit has been changed from tester to charger (by pressing the START/STOP button or auto
starting), it remains a charger as long as it’s connected to a battery. Press the START/STOP button
again to change back to tester mode.
13. BATTERY PERCENT AND CHARGE TIME (FOR MODEL DSR137)
This charger adjusts the charging time in order to charge the battery completely, efficiently and safely.
The duration of the charging process depends on three factors:
Battery State
If a battery has only been slightly discharged, it can be charged in less than a few hours. The same battery
could take up to 10 hours if very weak. The battery state can be estimated by using the built-in tester. The
lower the reading, the longer charging will take.
Battery Rating
A higher rated battery will take longer to charge than a lower rated battery under the same conditions. A battery
is rated in Ampere-Hours (AH), Reserve Capacity (RC) and Cold Cranking Amps (CCA). The lower the rating,
the faster the battery will charge.
