Installation manual

Page 62 IM-487
Actuator Rotation Adjustment
The counterclockwise (as viewed from shaft end of actuator)
limit switch is adjustable on the Barber-Colman actuator. The
clockwise limit is not adjustable. The counterclockwise limit
setting can be changed in the field by inserting a screwdriver
through the opening in the top plate directly ahead of the ter-
minal block on the shaft side and engaging the screwdriver
blade with the edge of the notched cam nearest the front of
the actuator. Turning the cam clockwise (as viewed from the
shaft) increases the amount of actuator rotation. Each click of
the cam represents about 3 degrees of change in actuator
rotation. Set the actuator for 180-degree rotation.
DWDI Housed Supply Fan Vane Adjustment
Figure 56 on page 63 shows the supply fan vane linkage
assembly. Both sets of vanes on the supply fan must operate
in unison. Adjustments to the motor rod end and locknut
(Point A) as well as to the floating link ends (Point C) can be
made to provide uniformity between the linkage assemblies.
The vane actuators must have 180-degree rotation. Do not
make linkage adjustments to compensate for improper actua-
tor rotation, but correct the actuator rotation adjustment.
Refer to “Actuator Rotation Adjustment”
Note: There are three different actuator rotation configura-
tions. These are shown as three views in Figure 56
on page 63. Refer to Table 13 to determine which
view applies to a particular unit.
On units with vane controls on both the supply and return fan,
it is important that both actuators have exactly 180-degree
rotation to provide proper 'tracking" of the two actuators.
SWSI Supply Fan Vane Adjustment (RAH Only)
Refer to Figure 57 on page 64 for 40" wheels, Figure 58 on
page 64 44" wheels, and Figure 59 on page 65 for 49"
wheels. The vane actuator must have 180-degree rotation. Do
not make vane adjustments to compensate for improper rota-
tion, but correct the actuator rotation adjustment. (Refer to
“Actuator Rotation Adjustment” )
As the actuator moves from 0 degrees to 180 degrees, the
vanes should move from 0 degrees (closed) to 90 degrees
(full open). This can be adjusted by changing the linkage rod
length by loosening the nut and sliding the rod at Point A or
Point B and retightening the nut.
Return Fan Vane Adjustment
Refer to Figure 57 on page 64 for 40" wheels in the RAH 47,
Figure 58 on page 64 for 44" wheels and Figure 62 on
page 66 for all RDS 800-802 return fans (30" and 40"
wheels). The vane actuator must have 180-degree rotation.
Do not make linkage adjustments to compensate for
improper rotation, but correct the actuator rotation adjust-
ment. (Refer to “Actuator Rotation Adjustment” )
As the actuator crankarm rotates from 0 degrees to 180
degrees, the vanes should move from 0 degree (closed) to 90
degrees (full open). This can be adjusted by changing the
linkage rod length by loosening the nut and sliding the rod at
Point A or Point B and retightening the nut.
NOTICE
Inlet vanes must not be adjusted to close tight during
fan operation.
A minimum operating position of 5 degrees open is rec-
ommended to avoid pulsation.
Units with factory installed MicroTech II controls will auto-
matically open vanes 5 degrees prior to start-up.