General Functions - Mitsubishi Electric MELSEC iQ-R Series Safety Function Block Reference

2.3

General Functions

Whether safety FBs are active or not
Input signal, i_bActivate, sets whether to activate a safety FB or not. In addition, whether the safety FB is active or not can be
checked with output signal, o_bReady. If i_bActivate is OFF, all values of the output signals are set to the default values.
Inputting the signal of the safety refresh communication status for CC-Link IE Field Network inactivates the safety FB when an
error occurs in the safety station and then prevents unnecessary signals from outputting.
Reset selection
A reset method of safety FBs can be selected from i_bS_StartReset (after safety FBs are activated) and i_bS_AutoReset
(after safety inputs are restored).
■ Manual reset
In this method, a safety output signal is not set to ON immediately even though safety input signals are correctly set. By
changing i_bReset safety input signal from OFF to ON while the safety input signals are correctly set, the safety output signal
is set to ON.
■ Automatic reset
In this method, a safety output signal is immediately set to ON when safety input signals are correctly set.
WARNING
The automatic reset can only be activated if it is ensured that no hazard can occur when a safety FB is activated (with i_bS_StartReset input) or a safety input
is set (with i_bS_AutoReset input). (Also, the manual reset switched from the automatic reset or the automatic reset switched from the manual reset can be
activated.)
Therefore, the use of automatic reset requires implementation of other systems or application measures to ensure that unexpected (or unintended) startup
does not occur.
Securing of input signal Reset
To prevent a machine startup in the event of switch failures (contact welding, damaged springs), the safety FB can only be
activated when Reset input signal is set to ON. If Reset remains ON without detecting that it is set to ON, the safety FB
detects an error.
Safety FB status check
The current status of safety FBs can be checked with output signal, o_wDiagCode (hexadecimal number). If an error occurs in
the safety FB, o_bError output signal is set to ON and an error code is output to o_wDiagCode. If more than one error occurs,
only the error code corresponding to the error detected at first is output. If an error does not occur in the safety FB, o_bError
output signal is OFF and a status code is output to o_wDiagCode.
WARNING
Take action against error messages and perform reset operations properly.
2 GENERAL SPECIFICATIONS
2.3 General Functions
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