User Guide

VA-715x Electric Valve Actuator Product/Technical Bulletin 5
Incremental Control--VA-7150
1
2
3
Common
Down
Up
From
24 VAC
Suppl
y
Figure 10: Basic Incremental Wiring
Table 2: VA-7150 Action
Energizing Terminals Actuator Drive Screw
1-2
Extends
1-3
Retracts
Incremental control wiring should be connected to
terminals: (1) Common, (2) Down, and (3) Up.
(Terminal 17 is not used.) Providing power to
Terminals 1 and 2 will cause the actuator drive screw
to extend, pushing the valve stem down. Providing
power to Terminals 1 and 3 will cause the actuator
drive screw to retract, pulling the valve stem up.
Incremental Control with Feedback--
VA-7153
2k ohms
Down
From
24 VAC
Suppl
y
S
W
R
1
2
3
Common
Down
Up
Figure 11: Basic Feedback Wiring
Table 3: VA-7153 Resistance Change
Actuator Drive
Screw
Feedback Resistance
Change
R - W W - S
Extends
Decrease Increase
Retracts
Increase Decrease
Incremental control wiring should be connected to
terminals: (1) Common, (2) Down, and (3) Up.
Providing power to Terminals 1 and 2 will cause the
actuator drive screw to extend, pushing the valve stem
down. Providing power to Terminals 1 and 3 will cause
the actuator drive screw to retract, pulling the valve
stem up.
The position feedback potentiometer is connected to
Terminals R, W, and S. Terminals R and S are a fixed
2000 ohm resistance. The potentiometer wiper is
connected to Terminal W. Resistance change vs.
actuator travel is shown in Figure 12.
Stem
Up
Stem
Down
Terminals
R and W
Terminals
W and S
Increasing Resistance
Figure 12: Feedback Resistance
Proportional Control--VA-7152
4
3
2
Common
Common
1
+
Suppl
y
24 VAC
Controller
Input Si
g
nal
Figure 13: Basic Proportional Wiring
Note: Terminals 2 and 3 are tied together on the
circuit board.
Table 4: VA-7152 Action
Input Signal
Actuator Drive Screw
DA RA
Increase
Extends Retracts
Decrease
Retracts Extends
Voltage supply wiring should be connected to
terminals: (1) AC and (2) Common. Control wiring is
to terminals (3) Common (-) and (4) IN (+).
With a low control signal voltage applied across
Terminals 3 and 4, the actuator drive screw will be fully
retracted in Direct Acting (DA) mode, and fully
extended in Reverse Acting (RA) mode. With a high
control signal voltage applied across Terminals 3
and 4, the actuator drive screw will be fully extended in
Direct Acting (DA) mode, and fully retracted in Reverse
Acting (RA) mode.