
5. USING THE BATTERY
27
• Charging while operating from DC12V external battery
This function is useful when operating from the BT-53Q rechargeable battery that is low and
needs charging.
Using the instrument with 12vDC external battery in ambient temperature
[10 to 35°C (50 to 95°F)], the rechargeable battery can be recharged while the instrument is
in use.
Optional accessory power cable (PC-17) is necessary to use the instrument with 12vDC
external battery.
“5.3 PC-17 (Power cable for 12vDC) *Optional accessory” (p.30)
Connect 12vDC external battery and turn the instrument ON, the BT-53Q will charge
automatically. The charging indicator LED on top of the BT-53Q will indicate charging status.
• The LED on the battery indicates charging status as follows:
Red ON
: Charging
Green ON
: Charging completed.
Green flashing : Internal error of BT-53Q rechargeable battery
Red flashing
: BT-53Q rechargeable battery protection feature* is working automatically.
The instrument can be used in this case.
*Automatic protection feature:
In case of overcharge or high or low ambient temperatures that exceeds charging
temperature range, charging will be stopped or changed to protect battery.