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FREQUENTLY ASKED QUESTIONS
Q. How do I know if the battery is charged?
A. The battery charger’s GREEN ‘FULLY CHARGED’ LED will illuminate to indicate when the battery is fully
charged. Alternatively use a Battery Hydrometer (Projecta Part No. BH100). A reading of 1.250 or more
in each cell indicates a fully charged battery.
Q. Why does the battery charger have two ratings?
A. Battery chargers for automotive use have traditionally been given an RMS rating in the past. This rating
is now used as an industry reference only. Australian Standards now require all battery chargers to be rated
at the charger’s continuous output at a nominated voltage, we express this as mA (milliamps) rather than
A (Amps) to avoid confusion.
Q. Why does the ‘FULLY CHARGED’ LED come on straight away?
A. There are four possible reasons why the ‘FULLY CHARGED’ LED may come on straight away.
1. The battery is fully charged.
2. The battery has taken a surface charge.
3. The battery has a faulty cell.
4. The BATTERY VOLTAGE setting on the charger is set lower than the battery voltage.
Q. What is Surface Charge?
A. Batteries unused or left flat for some time build up a resistance to being recharged. When the charger is
first connected, these batteries will take a surface charge, and the ‘FULLY CHARGED’ LED will illuminate
within a short while. The battery however is not fully charged, the charger is voltage sensitive and cannot
differentiate between a surface charge and a fully charged battery. After a few hours the battery may start
to accept some charge but most batteries with this condition will not recover.
Q. What is a Faulty Cell?
A. 12 Volt batteries contain 6 cells and one faulty cell is enough to ruin your battery. If after eight hours of
charging your battery is still flat, you should test the cells using a hydrometer. If one reading is lower than
the rest it indicates a faulty cell. It is pointless to continue charging, as the battery needs replacing.
Q. I have connected the charger properly but the ‘Orange’ charging light does not come on?
A. In some cases batteries can be flattened to the point where they have very little or no Voltage. This can
occur if a small amount of power is used for a long time, for example a map reading light is left on for a
week or more. Projecta automatic chargers are designed to charge from as little as 3 Volts. If the voltage
is lower than 3.0V press the override button to start the charger.
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