Pilz PSS SB FT, Basic license - Manual (Page 167)

8-3 Modular Block System: Burner Management
ERR: If an error is present a controlled shutdown occurs, with
AuSt = 1 automatic start (without reset).
CHAI: If an error is present a safety shutdown occurs.
The following SBs are a component part of this group:
- SB060 (E_STOP cat.2)
- SB061 (E_STOP cat.4)
- SB067 (Feedback loop)
- SB151 (Transient suppression)
- SB153 (Drive and position monitoring of the flaps)
- SB154 (Drive and position monitoring of the valves)
• ENBL of the SBs without RSET as input parameter, but with NEXT
as input parameter and
RDY as output parameter.
For all SB enables whose error messages are reset from the step
sequence SB149, the negative edge must be monitored in the
application program. The negative edge should set a flag to “0” for one
PSS-cycle. This pulse flag must be supplied to the AND-operation before
the global input
ERR or to the AND-operation before the global input
CHAI from SB 152 “Burner: Start and operator elements”. The decision
for
ERR or CHAI depends on the user and the respective standards
regarding error reaction.
ERR: If an error is present a controlled shutdown occurs, with
AuSt = 1 automatic start (without reset)
CHAI: If an error is present a safety shutdown occurs
The following SBs are component parts of this group:
- SB155 (Pre-purge)
- SB156 (Tightness control)
- SB158 (Ignition)
- SB159 (Run)