Pilz PSS SB FT, Basic license - Manual (Page 50)

6-6 Modular Block System: Burner Management
Standard Function Blocks SB149
• RDY and NEXT
The output parameter NEXT from the current step must be supplied to
the input parameter RDY of the following step. This ensures that when
the next step is activated, the previous step is deactivated, thereby
ensuring only one step is active at any given.
• Activating a step
- To activate a step: the ready signal from the previous step must be
present ( RDY = 1) and all step enabling conditions must be fulfilled
( COND = 1).
- As soon as a step is active, the following occurs:
° output parameter NEXT from the step is set to 1
° the input parameter RDY of the current step and also the output
parameter NEXT from the previous step are reset to 0
° if W_V > 0, step monitoring time W_V is started
° if D_V > 0, time delay D_V is started,
otherwise D_E is immediately set to 1
SB152
BR_START
B - SSNR
X - NEXT
X - STRT
X - STOP
X - ERR
X - GUAR
X - AirP
X - CHAI
X - FLAs
X - FTRY
X - RUN
B - D_C
X - AuSt
X - RSET ENBL - X
RDY - X
STEP - X - M 80.00 .Burner2