Canon BJC-55 Series, Сервисный бюллетень

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a) Pre-recharging Circuit
When the lithium ion battery voltage is low, the pre-recharging circuit and small
amounts of electrical current are used to raise the voltage. Once the voltage level
rises to the normal level, this circuit is stopped.
b) Constant Current/Voltage Recharging Circuit
Constant current is maintained until the lithium ion battery voltage reaches 12.3 V.
Once it reaches 12.3 V, the control mode switches to constant voltage to maintain a
stable 12.3 V supply. When the voltage is less than 6 V, the ICP2 blocks recharging
and the battery will not start recharging even after receiving a charge ON signal.
4.3.4 Lithium Ion Battery
a) Properties of the lithium ion battery
Advantages of a lithium ion battery are the high concentration of electrical energy,
high rate of charge preservation and no memory effect. Also, it contains no toxic
compounds such as cadmium, lead or mercury.
However, once the battery is over discharged beyond zero charge, the battery may
deteriorate rapidly. Under high temperatures, self-discharge is accelerated and this
may lead to rapid over discharge. Chances of reviving an over discharged battery
that was left unused for an extended period of time is very slim. Over discharge can
be prevented by regularly charging the battery. The battery must not be stored in
high temperature places.
b) Recharging mechanism
The recharging circuit for the battery is found on the printer. With power supply
from the Universal adapter, the battery is charged using the constant
current/constant voltage recharging process. The battery is recharged automatically
when the printer is either OFF or ON but in stand-by. When a BJ cartridge is
installed, recharging will take place only if the BJ cartridge is capped. In other
words, recharging will stop temporarily during printing or when the cartridge is
uncapped. When the scanner cartridge is installed, recharging takes place when the
scanner driver is not operating.
The voltage of the Lithium ion battery cannot be measured directly.
Low charge is indicated by the charge indicator lighting green when the
battery is installed in the printer and the Universal adapter is plugged.
Part 4: Technical Reference
BJC-50
4-42