Mitsubishi Electric Q06CCPU-V-H01, Руководство пользователя

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8
3.2 Fail-safe Circuit
DANGER
z Provide a safety circuit outside the C Controller module to
ensure that the entire system will operate safely even if an
external power failure or C Controller module failure
occurs.
Failure to do so could result in accidents due to erroneous
output or operation.
(1) For an emergency stop circuit, protection circuit and
interlock circuit that is designed for incompatible
actions such as forward/reverse rotation or for damage
prevention such as the upper/lower limit setting in
positioning, any of them must be provided outside the C
Controller module.
(2) When the C Controller module detects the following
conditions, it will disable the output (Y) from the user
program and writing to buffer memory in the case of
both (a) and (b) and turn off all outputs for (b).
Whether to hold or clear all the outputs is set by a
parameter.
(a) The overcurrent protector or overvoltage protector
of the power supply module is activated.
(b) An error such as a watchdog timer error is detected
by the self-diagnostic function of the C Controller
module.
If an error occurs in I/O control parts and the C
Controller module cannot detect the error, all the
outputs may turn ON.
Provide a fail-safe circuit or a preventive mechanism
outside the C Controller module so that machines will
operate safely in such a case.
(3) Output could be left on or off when there is a fault in an
output module relay or transistor.
So build an external monitoring circuit that will monitor
any output signal that could cause serious accidents.
z If load current more than the rating or overcurrent due to a
short circuit in the load has flowed in the output module for
a long time, it may cause a fire and smoke. Provide an
external safety device such as a fuse.
z Create the circuit so that the external power supply will turn
on after the C Controller system is powered on.
Turning on the external power supply first could result in
accidents due to erroneous output or operation.
z For each station's operating status in the event of a each
station error, refer to the corresponding each station
manual.
Not doing so could result in erroneous output or operation.