Mitsubishi A2USCPU(S1), User Manual

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SAFETY PRECAUTIONS
(Be sure to read these instructions before use.)
Before using the product, read this and relevant manuals carefully and handle the product correctly with full
attention to safety.
In this manual, SAFETY PRECAUTIONS are classified into 2 levels: "DANGER" and "CAUTION".
Under some circumstances, failure to observe the CAUTION level instructions may also lead to serious
results.
Be sure to observe the instructions of both levels to ensure the safety.
Please keep this manual in a safe place for future reference and also pass this manual on to the end user.
[DESIGN PRECAUTIONS]
DANGER
Create a safety circuit outside the programmable controller to ensure the whole system will operate
safely even if an external power failure or a programmable controller failure occurs.
Otherwise, incorrect output or malfunction may cause an accident.
(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 created outside the programmable
controller.
(2) When the programmable controller detects the following error conditions, it stops the operation
and turn off all the outputs.
• The overcurrent protection device or overvoltage protection device of the power supply
module is activated.
• The programmable controller CPU detects an error such as a watchdog timer error by the
self-diagnostics function.
In the case of an error of a part such as an I/O control part that cannot be detected by the
programmable controller CPU, all the outputs may turn on. In order to make all machines
operate safely in such a case, set up a fail-safe circuit or a specific mechanism outside the
programmable controller. Refer to "LOADING AND INSTALLATION" in this manual for example
fail safe circuits.
(3) Depending on the failure of the output module's relay or transistor, the output status may remain
ON or OFF incorrectly.
For output signals that may lead to a serious accident, create an external monitoring circuit.
DANGER
Indicates that incorrect handling may cause hazardous conditions, resulting in
death or severe injury.
CAUTION
Indicates that incorrect handling may cause hazardous conditions, resulting in
minor or moderate injury and/or property damage.