Recharging; Low Battery; Continuous Operation - Wahl Heat-Prober 2500MX Instruction Manual

2.3.1 Recharging

To recharge the batteries, use the recharger supplied. Plug in directly to a 120-volt,
60-cycle wall plug and insert the jack into the socket on the left side of the Heat-
Prober. (For overseas 220-volt lines, use a Franzus converter adapter with the recharg-
er supplied or request a 220-volt recharger).

2.3.2 Low Battery

Ni-Cad batteries have a stable voltage throughout their charge life. Near the end of the
power cycle the voltage will drop abruptly. This voltage is sensed by the meter.
Low-battery indication is registered on the display by "L" on LED models and "LO
BATT", or "←", on LCD models. This indicates that you have approximately two minutes
to complete your measurement. After that, the falling battery voltage may cause erro-
neous readings. Continued use of the meter will result in total loss of display. The
recharger should be put on immediately after the low battery light comes on. Recharge
time is 10 to 12 hours, but a partial charge can be obtained in 1 hour or less.

2.3.3 Continuous Operation

The Heat-Prober can be continuously operated by using a battery recharger to restore
or recharge the batteries as they are depleted. The instrument operates from the bat-
teries only. The recharger will charge the batteries with the switch "OFF", or make-up
battery power when the instrument is operating. The recharger supplied with the
instrument will enable continuous operation. It the battery pack is in an extremely low
charge condition, it may take two to three minutes before the display will function.
NOTE: The instrument cannot rectify AC current. A DC charger with open circuit volt-
age of 9 volts and approximately 120 milliamperes will maintain the battery charge.
This occurs when the switch is on and the instrument is operating. Do not connect a
voltage source to the batteries unless its current is limited to 120 milliamperes.
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