Mitsubishi Electric MELSEC iQ-R Series Safety Manual page 30

■When using a safety CPU and a safety remote I/O module (connecting extension module)
Connect the emergency stop switch to the main module of the safety remote I/O module. Connect the safety relay to the same
extension module of the safety remote I/O module. Safety CPU controls on/off of the safety relay according to the input from
the emergency stop switch.
• PFDavg/PFH of A: PFDavg/PFH value of a Safety CPU (paired with the safety function module) on the safety path
• PFDavg/PFH of B: PFDavg/PFH value when connecting the extension module (B2) to the main module (B1)
• PFDavg/PFH of C: Do not add this to PFDavg/PFH, since it uses safety remote I/O module same as B (A safety device can
be added for only once per safety path).
• PFDavg/PFH of D: PFDavg/PFH value of the emergency stop switch
• PFDavg/PFH of E: PFDavg/PFH value of the safety relay
PFDavg = (PFDavg of A) + (PFDavg of B1 and B2) + (PFDavg of D) + (PFDavg of E)
-5
= (1.02  10 ) + (4.66  10
-5
= (5.68  10
) + (PFDavg of D) + (PFDavg of E)
PFH = (PFH of A) + (PFH of B1 and B2) + (PFH of D) + (PFH of E)
-9
= (5.50  10 ) + (4.78  10
-8
= (1.03  10
) + (PFH of D) + (PFH of E)
A
B1
Input
D
Emergency
stop switch
4 PRECAUTIONS FOR USE OF SAFETY PROGRAMMABLE CONTROLLER
28
4.1 Precautions for Designing Safety Application
-5
) + (PFDavg of D) + (PFDavg of E)
-9
) + (PFH of D) + (PFH of E)
B2
Output
E
Safety
relay