ETS-Lindgren HI-6153 Electric Field Probe - Manual (Page 94)

94 | Series H-491198-48 Battery Charger for NiMH Batteries
B ATTERY L IFE
The NiMH battery powering the battery-operated probe has high energy density
for maximum operating time between charges, but also has a significant self-
discharge characteristic. When the probe is stored for longer than a week or two,
the battery will discharge even though not in use. Leaving the battery in a
discharged condition for long periods of time may result in reduced battery life.
For optimum testing time, charge the battery before use.
The battery charger is microprocessor controlled to charge the battery in the
fastest possible manner. When the charger senses that the battery is fully
charged, the charging current drops to a maintenance level. This level is
sufficient to maintain the battery fully charged without causing battery damage. It
is acceptable to leave the probe connected to the battery charger for extended
periods of time.
With proper care, the battery should last two to three years. Follow these
recommendations to ensure maximum battery life and optimum testing
performance:
 Set the power switch on the probe to the OFF position when the probe
is not in use. Leaving the power switch in the ON position for extended
periods of time will damage the battery. When the battery is
discharged, the flashing power
ON indicator will not function.
 When possible, leave the probe connected to the battery charger, and
the battery charger connected to the mains electrical supply (charger
operating). The battery charger status indicators will show
CHARGER
ON and COMPLETE when the battery is on a maintenance charge.
 Operate the probe only within the optimum operating temperature
range of +20
º C to +30 º C (+68 º F to +86 º F). Although NiMH batteries
are rated for operation in temperatures from -20 º C to +65 º C
(-4 º F to +140 º F), operating the probe at temperature extremes
reduces the operating time of the batteries.
 Make sure the battery is fully charged before resuming operation. The
battery does not require periodic deep discharges to reverse the effect
caused by repeated shallow discharges, but undercharging can reduce
battery capacity.