As a means of protection for the power supply PCB, the AC power supply input sideis equipped with a fuse and each DC circuit is equipped with a built-in overcurrentprotection circuit.If an overcurrent flows because of a short circuit in the power supply line, theprotection circuit will turn on to turn OFF the output of the power supply unit. If suchhappens, disconnect the power plug, and remove the cause of activation; then, turn ONthe power supply. The protection circuit may be reset by turning ON the AC power supplyonce again after keeping the AC power supply of the power supply unit OFF for about30 sec.If an overcurrent flows, the protection circuit turns on before the fuse of the AC inputblows; however, the AC input fuse may blow if the AC power supply is turnedON/OFF while the output of the power supply unit has a short circuit.C. Power Supply for Date/Time DisplayThe DC controller PCB is equipped with a lithium battery as a backup to be used inthe event that the power plug is disconnected by accident.The lithium battery is good for about five years with the power plug disconnected.When its life is exhausted, the date/time notation remains unchanged; the notationmechanism starts to operate once again when the power plug is connected.You cannot use the lithium battery once it reaches its life, i.e., you cannot rechargeit. (Replace it with a service part battery.)The service part battery will not discharge unless it is connected to a circuit, and it isgood as long as five years after it is first used.Keep in mind that the backup data will be lost when the battery reaches its life orwhen it is taken out for replacement; be sure to re-enter data as necessary.Replace the lithium battery only with the one listed in the Parts Catalog.Use of another battery may present a risk of fire or explosion.The battery may present a fire or chemical burn hazard if mistreated.Do not recharge, disassemble or dispose of it in fire. Keep the battery out of reachof children and discard any used battery promptly.COPYRIGHT © 1997 CANON INC. CANON NP6045 REV. 1 MAR. 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)CHAPTER 7 EXTERNALS/AUXILIARY MECHANISMS7-11Caution:Caution:
