Protective Functions - Canon iR3245 Series Service Manual

Chapter 9

9.4 Protective Functions

9.4.1 Protective Functions
iR3225 / iR3225N / iR3235 / iR3235N / iR3245 / iR3245N
As part of its protective mechanism, the machine has a thermo switch (TP1), triacs, and a relay.
Protective measures according to location are described below:
When the thermistor is out of order
Software detects a failure, and the triac and the relay are turned off.
The thermo switch is turned off.
When the CPU goes out of control
The latch circuit detects the excessive temperature rise, and the relay is turned off.
The thermo switch is turned off.
When the triac short-circuits
Software detects failure, and the relay is turned off.
The latch circuit detects the excessive temperature rise, and the relay is turned off.
The thermo switch is turned off.
9-6
DC-CON
Relay control
Triac control 1
CPU
Triac control 2
A/D
Latch circuit(M)
Latch circuit(S)
Tr
Connection detection
S_TH M_TH
Thermo switch
and
and
and
and
Fixing unit
AC driver
Triac 2
Triac 1
Relay
F-9-5
0018-9786