11. MOVING TO THE
LOW FIRE
POSITION
The safety shutdown output (PC1-2) and the controlled shutdown
output (PC3-4) are both closed.
All selected drives (motors and inverters) are driven to their low fire
(P3) positions.
The unit will proceed to status 12 if :
• The drives have stopped moving.
• The low fire hold time has expired (see option parameter 08.2)
• If selected, a 'release to modulate' signal is received via serial
comms or an auxiliary input (see option parameters 15.1 and
15.2)
If the burner select input (PC12) is turned off or the profile selection
(PC13, 14 and/or 17) is changed the unit returns to status 3 (or status
13 if a post purge has been selected using option parameter 09.1).
The high/low initiate input (PC11) is ignored.
If the drive positions are outside the ignition and low fire positions, the
unit will change to status 2 with a drive positioning fault.
12. MODULATION The unit modulates all selected drives in ratio to the required
modulation rate. Trim will be applied after the transport delay has
expired (if selected).
If the burner select input (PC12) is turned off, the profile selection
(PC13, 14 and/or 17) is changed or the measured value exceeds the
high control limit, the unit returns to status 3 (or status 13 if a post
purge has been selected using option parameter 09.1).
The high/low initiate input (PC11) is ignored.
If any selected drive deviates from its profile setpoint, the unit will
change to status 2 with a drive positioning fault.
13. MOVING TO
POST PURGE
The safety shutdown output (PC1-2) is closed but the controlled
shutdown output (PC3-4) is open, preventing the burner from firing.
All selected air and option drives are driven to their purge (P1)
positions.
All fuel drives are driven to their close (P0) positions.
The unit will proceed to status 14 when the air and option drives have
stopped moving.
The burner select input (PC12), profile select inputs (PC13, 14 and
17) and the high/low initiate input (PC11) are ignored.
14. POST PURGE The safety shutdown output (PC1-2) and the controlled shutdown
output (PC3-4) are both closed.
All selected air and option drives are driven to their purge (P1)
positions.
All fuel drives are driven to their close (P0) positions.
The unit will return to status 3 when the post purge time has expired
(see option parameter 09.1).
The burner select input (PC12), profile select inputs (PC13, 14 and
17) and the high/low initiate input (PC11) are ignored.
If the measured air or option drive positions do not match P1, the unit
will change to status 2 with a drive positioning fault.