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Option 4.5 - Permanent gas pilot select (0 -1 intermittent pilot)*
This option parameter allows the selection of permanent pilot operation when the burner is firing on
gas. When firing on oil this operating parameter is ignored.
Option 4.6 - Pilot valve with/without main valve selection (0-1)*
This option parameter allows the selection of pilot operation with or without the main gas valve (#1)
when firing gas. When firing oil, this parameter is ignored and the pilot valve always operates with-
out the main gas valve. The option parameter should be set to suit the configuration of the gas train.
Option 4.7 - Limit Modulation
By default, the control modulator the burner between the set-points P3 (low fire) and Px (high fire),
where Px is the last set-point entered in commission rate mode. If oxygen trim is used, it is not possi-
ble for any drive position to be trimmed lower than point P3 (low fire) or higher that point PX (high
fire).
This option parameter allows the normal modulation range of the burner to be limited so that the
burner may only modulate between points P4 (one se-point above low fire) and Px-1 (one set-point
below high fire). Since oxygen trim is not affected by this limitation, each drive may be trimmed
between the points P3 and Px. This means that it is not possible to over-fire or under-fire the burner,
but full trim may still be achieved and high and low fire.
Option 4.9 - Direct Ignition on Oil (0/1)*
This Option allows the selection of direct ignition when firing oil. The main oil valve is energized at
Stage 11, refer to Table 1.
Option 5.1 and 5.2 - Lead drive for gas and oil respectively (0 - 1)*
These option parameters set the lead drive for the gas and oil profiles.
Note: The other drives do not ‘lag’ behind the lead drive - all drives move in step and stay in ratio
during modulation. Instead, the lead drive is used to calculate the current modulation rate and for
drive position checking. For this reason, the lead drive position should not be the same for any two
profile setpoints. If this is the case, the lead drive should be changed from fuel to air or vice versa.
Choose the servo-motor that has the furthest travel. Do not choose a servo-motor with a flat curve.
0
Non permanent pilot. (Interrupted pilot)
1
Permanent pilot operation, when firing on gas. (Intermittent pilot)
0
Pilot operates without the main gas valve when firing on gas.
1
Pilot operates with the main gas valve (#1) when firing on gas.
0
Not limited. Burner modulates from P3 to Px -Oxygen trim works over full range from P3 to Px
1
Normal modulation range limited to P4 to PX-1 -Oxygen trim works over full range from P3 to Px
0
Lead drive is air damper
1
Lead drive is currently selected fuel
