Mitsubishi Electric MELSEC iQ-R Series - Page 87

5 SAFETY APPLICATION CONFIGURATION EXAMPLES
5.1 System Configured by a Safety CPU
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5
■Timing chart
Safety relay contact welding detection in this example (The same applies to other examples in this manual.)
M+SF_EDM_R is a safety FB that checks contact welding of safety relays or safety contactors connected to safety outputs of
a safety remote station. A safety remote station has the double input discrepancy detection function. Therefore, when either of
a safety relay or a safety electromagnetic contactor is welded, an error is detected both by the safety remote station and
M+SF_EDM_R. If either normally closed contact of safety relay is welded when o_bS_EDM_Out (output of M+SF_EDM_R)
turns on, M+SF_EDM_R does not detect the error while the safety remote station does. Accordingly, the program is created
using SA\SD1008 (Safety refresh communication status of each safety connection) to which the normally closed contact of
safety relay is connected so that i_bActivate may turn off to turn off the safety output of M+SF_EDM_R.
For the safety special register areas for the safety refresh communication status of each safety connection, refer to the
following.
Page 42 Clearing error in the CC-Link IE Field Network
Reset
switch
pressed
Reset
switch
pressed
Reset
switch
pressed
Start
switch
pressed
Start
switch
pressed
Start
switch
pressed
Start
switch
pressed
Start
switch
pressed
Start
switch
pressed
Reset
switch
pressed
Emergency
stop switch
pressed
CCIEF
remote (1)
error
When the reset switch is pressed,
the M+SF_ESTOP_R safety output
(SA\M1) is turned on, enabling the
M+SF_EDM_R.
When an error occurs in a safety remote
I/O module, inputs and outputs of the safety
remote I/O module are turned off.
Also, the M+SF_ESTOP_R and
M+SF_EDM_R are disabled.
When the start switch is
pressed, the M+SF_EDM_R
safety output is turned on
and the safety relay output
(SA\Y0) turns on.
Emergency
stop switch
pressed
Contact welding
detected in the
safety relay
When the emergency
stop switch is pressed,
the M+SF_ESTOP_R
safety output (SA\M1)
is turned off, disabling
the M+SF_EDM_R.
A safety remote I/O
module detects a double
input discrepancy.
Reset switch (reset_in)
M+SF_EDM_R reset input (SA\M3)
Safety refresh communication status
(SA\SD1008.0)
M+SF_EDM_R Error output (SA\M2)
M+SF_ESTOP_R safety output
(SA\M1)
Start switch (start_in)
Interlock status (SA\SD1232.0)
Interlock release request
(SA\SD1240.0)
Emergency stop switch (SA\X0)
Safety relay output (SA\Y0)
Safety relay output check (SA\Y1)