A/D conversion circuit diagnostic function
The R60DA8-G for diagnostics regularly inputs an analog value to the R60AD8-G set to SIL2 mode to internally diagnose the
A/D conversion circuit of the R60AD8-G.
Internal diagnostics is executed at the following timing.
• When the entire system starts operating normally after power-on (at start-up)
• In the cycle specified by "A/D conversion circuit diagnostic cycle setting" (during operation)
This function uses the SIL2 safety program FB (M+SIL2ADG_ADConv_R) and SIL2 standard program FB (M+SIL2ADG-
• During operation, A/D conversion circuit diagnostics is executed paired with the double input discrepancy
• If system switching occurs during A/D conversion circuit diagnostics, the A/D conversion circuit diagnostics
is suspended, and after the system switching is complete, the diagnostics is resumed at the point where it
• When the safety operation mode of SIL2 Process CPU is TEST MODE, the start-up A/D conversion circuit
diagnostics can be skipped by turning on i_bInitDiagSkip (start-up diagnostics skip request) of the SIL2
safety program FB (M+SIL2ADG_ADConv_R).
To use the A/D conversion circuit diagnostic function, the following module parameter setting and a program by the SIL2
diagnostic FB library are required.
• "A/D conversion circuit diagnostic cycle setting"
■"A/D conversion circuit diagnostic cycle setting"
Set a cycle to perform A/D conversion circuit diagnostics.
[Navigation window] [Parameter] [Module Information] [R60AD8-G(S2M)] [Module Parameter] [Application
setting] [A/D conversion circuit diagnostic cycle setting]
A/D conversion circuit diagnostic cycle setting
■Program by the SIL2 diagnostic FB library
With a project on the SIL2 Process CPU side, create a safety program and standard program and define the I/O of the SIL2
diagnostic FB library. Refer to the following to create programs.
Page 297 EXAMPLE OF OPERATION
10.8 SIL2 A/D Conversion Function
60 to 480min