20160778
32
GB
Start-up, calibration and operation of the burner
5.8.4
Intermediate outputs
Adjustment of gas delivery
No adjustment of gas delivery is required.
Adjustment of air delivery
Place the selector 1)(Fig. 38, page 29) in manual position.
Place the selector 2)(Fig. 38, page 29) in middle position and set
the variable profile cam 4)(Fig. 43) by turning the screws 5).
If the burner operation is low-high it is sufficient to set only
minimum and maximum firing rates
If the burner operation is modulating, all the points of modula-
tion should be adjusted.
When the adjustment is complete, switch off the burner using the
switch 1)(Fig. 38, page 29), OFF position, release the mechanical
cam 8)(Fig. 35, page 28) to separate the gears of the servomotor
(Refer to paragraph “Disengage the gears of the servomotor” on
page 29), and by manually turning several times the mechanical
cam 8)(Fig. 35, page 28) backwards and forwards check that the
movement is smooth and without any hindrance.
As far as is possible, try not to move those screws at the ends of
the mechanical cam that were previously adjusted for the opening
of the gas butterfly valve to MAX and MIN output.
5.9
TRIM potentiometers functions calibration
5.9.1
Range Adjustment range
Place the selector 1)(Fig. 38, page 29) in AUTO position and adjust
the range of the analog signal to match the switch positions (mini-
mum and maximum position):
1
Set cam I to the required high-fire position (e.g. 130°; position
is indicated on the scale next to the cam).
2
2. Set cam V to the required low-fire position (e.g. 15°).
3
3. Pre-set the signal at the analog input according to the
required high-fire position (e.g. 20 mA).
4
4. Turn the max potentiometer for maximum angular rotation
a) clockwise, if the actuator has not yet reached its maximum
angular rotation, or
b) counter-clockwise until the actuator starts
5
Pre-set the signal at the analog input according to the low-fire
position (e.g. 4 mA).
6
Turn the min. potentiometer for minimum angular rotation
a) counter-clockwise, if the actuator has not yet reached its
minimum angular rotation, or
b) clockwise until the actuator starts
Modulation always takes place between high- and low-fire.
Also, it is possible to define a closed position or a separate ignition
position by setting cam VI (independent of cam V, e.g. for defining
a position higher than the low-fire position).
NOTE:
When starting up, the direction of rotation of the potentiome-
ter setting must be observed (Fig. 45).
NOTE:
The working range of the potentiometer setting, shown as an
example for the current input 4 ... 20 mA (Fig. 46).
WARNING
We recommend binding the mechanical cams
8)(Fig. 38, page 29) to the servomotor.
Max.
Min.
135°
0°
Fig. 44
S9805
Max. potentiometer (high-fire)
Min. potentiometer (low-fire)
Max.
Min.
135°
0°
Fig. 45
S9806
20
18
16
14
12
10
8
6
4
2
0
min.
0°
max.
135°
(V)
(I)
30 60 90 120 135
Fig. 46
S9807
Set-point (l/mA)
Positioning angle (°)
