10
SERVOMOTOR (A)
The servomotor gives simultaneous regulation of the air
damper through the adjustable profile cam 4)(F) and the
pressure controller (A) pag. 11.
It rotates by 130° in approx. 35 s.
The factory settings must not be changed for the first fir-
ing, just check that they comply with the details below.
To open the servomotor, remove the screws and pull the
cover outward, fig. (A).
CAMS AND TRIM POTENTIOMETERS FUNC-
TIONS
Cam 1:
130°
Limits rotation towards maximum.
Cam 2:
0°
Limits rotation towards minimum, air damper closed on
stand by.
Cam 3:
20°
Limits ignition position.
Cams 4 - 5 - 6 - 7 - 8:
not used
Trim potentiometer MAX
Limits maximum modulation.
It must be set near the stroke end (cam 1) to exploit as
far as possible the variable profile cam.
Trim potentiometer MIN
Limits minimum modulation.
It must be set near the stroke end (cam 2) to exploit as
far as possible the variable profile cam.
Trim potentiometer POS
Limits an intermediate operating position between MAX
and MIN, supplying power to the "P" terminal in the ser-
vomotor (through an external command). This function
cuts out any external signals.
Note
Using the slide switch to select MAX or MIN, the servo-
motor goes into the position for the respective settings of
the MAX and MIN TRIM POTENTIOMETERS.
When the settings are complete, place the slide switch
on OPE.(operate)
(A)
(D)
(F)
D2277
(E)
1 Servomotor
2 Adjustable profile cam
3 Adjustment screws for cam
starting profile
4 Adjustment fixing screws
5 Adjustment screws for cam
and profile
D1229
(B)
D2585
NO
Figure above shows how the servo-
motor is released to manually check
there is no binding though its motion.
Don’t release the button indi-
cated in this figure: the syn-
cronization of the cams
made in factory would be
changed.
YES
(C)
Slide switch
Trim potentiometers
Position jumpers
