User Manual

Worcester Actuation Systems Series 75 Electric Valve Actuator FCD WCAIM2013-01 - 08/04
6
Options and Adjustments
(Factory Installed)
NOTE:
For wiring of the following options, please refer to the appro-
priate option wiring diagram(s) located inside actuator cover or
included with option kit. Wiring diagrams for most options are also
included in this manual for reference.
All wiring to terminal strip should be inserted only to mid-point of
terminal strip.
For some options with AC actuators, multiple wires are going to terminal
1. A short white wire is provided and connected to terminal 1, then
spliced to the other white wires (common) using a closed end splice.
A. Center-Off (180° Rotation)
1. Readjustment of “Center-Off” Cams (if necessary):
a. With the cover removed and the actuator placed with the
terminal strip facing the operator, switches 1 and 3 are to
the right and switches 2 and 4 are to the left of the main
shaft.
b. There are four cams and two spacers on the shaft. Per the
drawing on the following page, these cams are numbered
1 through 4, from bottom to top. (See proper drawing for
approximate location and correct orientation of the center-
off cams.)
c. Using the manual override (see page 12) as necessary, set
the actuator shaft to a “center-off” location.
Set cam #3 such that hook of switch 3 lever arm has just
dropped off the cam. Tighten cam screw without moving
cam.
a
CAUTION:
Do not bend the limit switch lever arm.
Set cam #4 such that hook of switch 4 lever arm will
match the arch of cam #4. Tighten cam screw without
moving cam.
a
CAUTION:
Do not bend the limit switch lever arm.
Release manual override.
d. Power the actuator to the full clockwise (CW) limit, to the
0° reference position. Check position of ball and valve stem
to verify that valve is in the true 0° position, as required by
the application.
e. Repeat the above step for the 180° or full CCW position.
Verify that the driven device is in the required position.
f. Apply power to terminals 1 and 7 for AC (+ to 7 and - to 8
for DC) to verify proper operation of center-off switches.
With the actuator shaft positioned at the 180° position,
power applied to terminals 1 and 7 for AC (+ to 7 and - to
8 for DC) moves the actuator shaft clockwise (CW) to the
center-off position.
With the actuator shaft at the full clockwise position, 0
degrees, apply power to terminals 1 and 7 for AC (+ to 7
and - to 8 for DC). The actuator shaft should move counter-
clockwise CCW to the center-off position.
View “A”
Typical View Showing Location of Center-Off Cams
and Limits Switches Set Up at the Center-Off Position
Standard 90° Actuator
Series 75W, X, and Z Shown
180° Center-Off Actuator Series 75W, X, And Z Shown