COPYRIGHT © 1999 CANON INC. CANON 660/2100 REV.0 FEB. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)C. Protective MechanismsThe +24 VB power supply circuit and the +5 V power supply circuit are equipped withan overcurrent protective mechanism and an overvoltage protective function, which auto-matically shuts off output voltage to prevent damage to the power supply circuits in theevent that a load should suffer a short circuit or overcurrent/overvoltage.If the overcurrent protective mechanism or the overvoltage protective mechanismturns on to cut of the DC voltage from the low-voltage power supply circuit, turn off thepower switch, disconnect the power cable, and correct the fault on the load in question;then, connect the power cable, and turn on the power switch.The circuit is quipped with a circuit breaker (CB101) and a fuse (F1), which shut offthe output voltage in response to overcurrent (i.e., CB101 turns off). If such has occurred,wait about 60 sec and then turn on the power once again.Note that an overvoltage blows F1 to shut off the power.CHAPTER 7 EXTERNALS/AUXILIARY MECHANISMS7-7Download free service manual at http://printer1.blogspot.com