Product Overview

D-9502 Product Bulletin 3
Starting Point
The starting point is the point at
which the actuator begins to
stroke. It is adjustable form 2 to
12 PSIG (14 to 84 kPa) using
the starting point adjusting
screw located under the cover
(see Fig. 3). Turning the screw
counterclockwise will increase
the starting point and clockwise
will decrease the starting point.
Note: The sum of the starting
point pressure and the
operating span must not
exceed the supply air
pressure to the positioner. A
typical supply pressure is
usually between 20 and
25 PSIG (140 and 175 kPa).
Maintain a starting point
pressure and corresponding
operating span accordingly.
Mounting
The D-9502 Positioner is
furnished with a mounting
bracket for attachment directly
onto the actuator body. When
mounting the assembly, allow
space for removal of the cover
and adjustment of the relay.
When a D-3000 Series Damper
Actuator is ordered with a
positioner, the positioner is
factory installed on the actuator
(see the appropriate actuator
product data literature for more
details).
Calibration
The following is a typical
example of how a D-9502
Positioner is used to adjust the
operating range and change the
span of a damper actuator.
Assume an actuator has a
spring range of 8 to 13 PSIG
(56 to 91 kPa) resulting in a
span of 5 PSI (35 kPa), and that
it is desirable to use a D-9502
Positioner to obtain an operating
range of 6 to 13 PSIG (42 to
91 kPa) resulting in a span of
7 PSI (49 kPa). To make the
adjustment, refer to Fig. 3 and
proceed as follows:
1. Attach one end of the
positioner spring to the hole
in the lever arm which
corresponds to a 7 PSI
span. The other end of the
positioner spring must be
relocated to make the
spring perpendicular to the
lever arm.
2. Apply a controller output
pressure of 6 PSIG to the
positioner.
3. Remove the positioner
cover and turn the starting
point adjusting screw
clockwise until the actuator
just begins to stroke. Note:
The output pressure
reading can be taken
either using a pressure
gage in the output line or
at the hypodermic needle
test point on the
positioner body.
4. Increase the controller
output to 13 PSIG. At this
point, the actuator should
be fully stroked.
Note: In some cases,
adjusting the starting point
will affect the operating span
and a different hole in the
lever arm will need to be
selected.
The D-9502 will now position the
damper actuator over a range of
6 to 13 PSIG.
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