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How you notice that a rechargeable battery is defective or old:
- The operating time of the unit working with the battery decreases considerably.
- The rechargeable battery does not accept charging any more (status LED of the charging chamber flashes red
immediately after inserting the batteries and does not switch over to fast charging (red light) after a longer period
of time).
Functional description of the FISCHER AMPS rack-mount Chargers:
The
FISCHER AMPS
ALC chargers have 4 resp. 2 charging chambers (ALC 49 resp. ALC 81) in which –
depending on the type of charger – 9 V block batteries are charged individually, or AA batteries are charged in
pairs. The AA batteries are charged in pairs because they are used in pairs in the UHF systems. Each of the
charging chambers is controlled separately. After inserting the charging box with the battery into the charging
chamber, a voltage measurement process detects whether the battery is extremely deep-discharged.
In this case, the battery is charged in refresh mode with a small amount of current until a voltage has been reached
which allows fast charging. In fast charging mode, the status LED of the corresponding charging chamber flashes
red. A defective battery which cannot be charged any more is therefore detected, because it does not reach the
voltage required for fast charging. When a regularly discharged battery is inserted, fast charging starts
immediately.
In fast charging mode, the status LED of the charging chamber lights red. After a qualifying period for
voltage stabilisation at the battery, the charging current is switched off for a short time and the voltage of the
battery is measured.
When the charging processor detects that the battery is fully charged, the fast charging current is switched off and
the battery is kept full by means of trickle charging until it is removed, while the status LED lights green. The
battery can remain in the Charger for an indefinite period of time without danger of overloading.
A fully charged battery is detected as "charged" after approx. 10 to 15 min. when charged again (i. e.
switching on the Charger) and changeover to trickle charging mode is made.
Commissioning:
Power cable:
Plug in the enclosed 2-pole power cable into the 2-pole mounting jack at the rear connector panel of the Charger.
Inside the charger, there is an isolated, encapsulated switching power supply with an input voltage of 90V to
250VAC with 50Hz to 60Hz. Therefore the unit does not need to be grounded by a 3-pole grounded power cable.
Voltage adjustment of the units is made automatically depending on the mains voltage. The integrated
mains adapter of the unit has an electronic overload protection for short-circuit, defect or overvoltage.
Switching on the Charger:
The mains switch with a green LED is at the front of the Charger on the left. After changeover to position "On", the
red status LEDs of the charging chambers flash for a short time and the green Power ON LED lights. If the
batteries have already been inserted the charging process starts immediately. When charging, the LEDs light red.
