Johnson Controls VA-8051 - Manual (Page 3)

VA-8051 Product Bulletin 3
Wiring is to a terminal strip
labeled DWN (Down), COM
(Common) and UP,
respectively. Wiring is to the
terminals labeled R (Retracted
end), W (Wiper), and S (Stroked
end) for the feedback
potentiometer.
(See Fig. 6).
Retrofit Installation
! CAUTION: Do not use on
valves having a stroke over
3/4 in. Actuator travel over
3/4 in. will damage the
actuator.
! WARNING: Equipment
Damage Hazard. Do not
drive the VA-8051 actuator
unless it is mounted to a
valve. This can result in
permanent damage to the
actuator.
1. Remove the V-3000
actuator, upper spring plate
and spring. (See Fig. 2).
a. Disconnect the air line
to the actuator.
b. Remove the actuator
by loosening the
actuator set screw on
the bottom of the lower
diaphragm case. Lift
the actuator off of the
valve.
c. Hold the stem
extension firmly with a
9/16 in. box-head
wrench and with a
small screwdriver,
loosen the stem locking
screw.
d. For V-3000 valves,
compress the spring
using the X-200-8058
spring compression
tool. For V-3800
valves, compress the
spring with hand
pressure.
e. Using a 9/16 in. box-
head wrench, unscrew
the stem extension. Lift
the spring and upper
spring plate off the
valve. Remove the
spring compression
tool if used.
f. Thread the lower spring
plate up the
centerpiece stuffing box
to increase spacing
between the spring
plate and the flat valve
yoke mounting surface.
2. Unpack the actuator and
make sure the lever plate is
within 1/4 in. of the upper
stop.
3. Install the valve packing
that is provided according
to the instructions included
with the parts.
4. Thread the 1/4 in. Palnut,
open side down, onto the
valve stem and all the way
to the end of the threads.
5. Loosely install the actuator
by sliding the actuator yoke
between the spring plate
and the yoke surface.
Finger tighten the plate to
hold the actuator in place.
(See Fig. 3).
6. Obtain a source of 24 volt
AC power. Wire a switch to
allow control of the 24 volts
AC to the DWN and COM
terminals of the actuator.
7. Thread the coupler onto the
valve stem while applying
24 volts AC as necessary.
The coupler should thread
down the stem until
approximately 1/8 in. of
thread remains between the
coupler and the Palnut.
Fig. 2: Exposed V-3000 Actuator