Schumacher Automatic PSW-70300A - Manual (Page 7)

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CONTROL PANEL 11.
Timer
Timer Setting: • The timer allows you to set a specified time for charging. After the
timer expires, the charger stops charging your battery. The main function of the
timer is to prevent over charging while allowing a battery time to obtain a satisfactory
charge. To properly set the timer, you must know the size of the battery in ampere
hours or reserve capacity in minutes and the state of charge. It is important that you
determine the appropriate state of charge of your battery as specified in Section 13
and set the timer accordingly.
Hold • : This position defeats the timer function, allowing for continuous operation.
Automatic Modes: • Put the timer in the HOLD position when using the battery
charger in one of the Automatic Modes (4, 20 or 70 amp), otherwise the timer
will stop the charging process when the time expires regardless of whether
it is complete or not. The CHARGED (green) LED will light when charging is
complete and the charger goes into Maintain Mode. The charger will not shut off.
Manual Modes: • Put the timer in the HOLD position when using the battery
charger in the Manual Mode (40 amp) and when you want to charge more than
2¼ hours. Be sure to monitor the charging progress and stop it when the battery
is charged. Not doing so may cause damage to your battery or may cause other
personal property damage or personal injury.
Ammeter
The Ammeter indicates the amount of current, measured in amps, that is being drawn
by the battery. As a battery takes on a charge, it draws less current from the charger.
Correspondingly, the meter will show less current being drawn by the battery. When the
current stops decreasing, the battery is charged. The 4 amp charge rate may indicate
some activity on the meter, although the meter does not have the resolution to display
this low rate.
Voltmeter
The voltmeter indicates the voltage at the battery terminals. The charger need not be
plugged into an AC outlet. The timer should be in the OFF position. Then connect the
charger following the instructions in Sections 6 and 7. Observe the meter indication.
Keep in mind that this reading is only a battery voltage reading, a false surface
charge may mislead you. We suggest that you turn on the headlights for a couple of
minutes before you read the meter. Read it a couple of minutes after you have shut
the headlights off. If the reading is less than 10.5-volts, the battery may be bad or the
connection at the charger may be poor. If the reading is 10.5-volts to 12.8-volts, the
battery is low – recharge it. If the reading is above 12.8-volts, the battery is charged.
Charge Rate Selector Switch
Use the Charge Rate selector switch to select the charge rate or engine starting setting
you require.
4A Slow Charge Rate • – Intended for charging small batteries such as those
commonly used in garden tractors, snow mobiles and motorcycles.
20A and 40A Fast and 70A Rapid Charge Rate • – Use for charging automotive,
marine and deep-cycle batteries. Not intended for industrial applications.
300A Engine Start • – Provides 300 amps for cranking an engine with a weak or run
down battery. Always use in combination with a battery.
OPERATING INSTRUCTIONS 12.
Automatic Temperature Compensation
The charger adjusts the maximum charge voltage and maximum maintain voltage based
on the ambient air temperature. This permits optimum charging and safety.
Thermal Runaway
The charger automatically reduces the current if it detects the battery may be getting too
hot. This is a safety precaution.
Charging
Ensure that all of the charger components are in place and in good working 1.
condition, including the plastic boots on the battery clips. Make sure the electrolyte
(battery liquid) in each cell is at the correct level.
Set the charge rate switch and the timer to the OFF position. 2.