Fail-Safe Measures When A System Of This Product Fails - Mitsubishi Electric MELSEC iQ-R Series User Manual

AC and DC power
1.
Turn the power of this product ON.
2.
Change the operating status of this product to the Y OUT state.
3.
RA2 turns ON when DC power is established.
4.
XM turns ON when RA2 turns ON, and the processing is started by a user program after DC input signal is fully
established.
5.
Turn the start switch ON.
6.
The output devices are activated by a user program when the relay (MC) turns ON.
User program
Create a program to perform the following operations when this product starts.
■Turning Ym ON when the battery voltage drop is detected
Use the mdBdReceiveEx function and the mdBdDevSetEx function.
■Turning Yn ON when the user program is started
Use the mdBdReceiveEx function and the mdBdDevSetEx function.
■Starting the system processing once XM turns ON and the DC input signal is established
(after DC input signal settling time)
Create a program that starts the system processing once the DC input signal setting time has passed after XM turns ON. The
ON status of XM can be checked with the mdBdReceiveEx function. (The DC input signal setting time indicates a time from
when RA2 turns ON to when the DC input signal is fully established. The time must be set to 0.5 seconds.)
However, the DC input signal settling time does not need to be set on the user program when using a voltage relay for RA2.

Fail-safe measures when a system of this product fails

Failures of this product can be detected with the self-diagnostics function; however, failures which occur in a part, such as an
I/O control part, may not be detected.
In this case, all inputs or outputs may turn ON or OFF, or normal operation and safety of the control-target device may not be
ensured depending on the failure.
Even though Mitsubishi programmable controllers are manufactured under strict quality control, they may fail due to some
reasons. Configure fail-safe circuits external to this product so that no machine is damaged and no accident occurs.
APPX
296
Appendix 9 General Safety Requirements