Pilz PSS SB FT, Basic license - Manual (Page 110)

6-66 Modular Block System: Burner Management
Standard Function Blocks
• Sequence for seal check
- NEXT = 0: Seal check was not activated
° Enable
→
ENBL = 1
° Seal check step not active
→
RDY = 0
° Safety valve closed
→
VAV1 = 0
° Main valve closed
→
VAV3 = 0
° Exhaust valve closed
→
VAV4 = 0
° Test output
→
GP- = 0
° Test output
→
GP+ = 0
- NEXT, Bit 00 = 1: Ventilate
° Enable
→
ENBL = 1
° Seal check step 1 is active
→
RDY, Bit 00 = 1
° Safety valve closed
→
VAV1 = 0,
if V4? = 0: open main valve
→
VAV3 = 1
if V4? = 1: open ventilation valve
→
VAV4 = 1
° Test output
→
GP- = 0
° Test output
→
GP+ = 0
- NEXT, Bit 01 = 1: Testing for air pressure
° Enable
→
ENBL = 1
° Seal check step 2 is active
→
RDY, Bit 01 = 1
° Safety valve closed
→
VAV1 = 0
° Main valve closed
→
VAV3 = 0
° Exhaust valve closed
→
VAV4 = 0
° Test output
→
GP- = 1
° Test output
→
GP+ = 0
- NEXT, Bit 02 = 1: Filling
° Enable
→
ENBL = 1
° Seal check step 3 is active
→
RDY, Bit 02 = 1
SB156