3 NM SERIES SPRING RETURN DIRECT COUPLED ACTUATORS
31-00141M—03
4
Fig. 3. Spring Return DCA mounting orientation.
Measure Damper/Valve Shaft Length
If the shaft is less than 3.25 in. long for SCSA, the shaft
coupling must be located between the damper/valve and
actuator housing. If the shaft length is more than three
inches, the shaft coupling may be located on either side of
the actuator housing.
If the coupling must be moved from one side of the
actuator to the other, reverse the spring return direction
and flip the actuator. Follow these instructions (see Fig. 4):
1.
Remove the retainer clip from the shaft coupling and
set it aside for later use.
2.
Remove shaft coupling from one side of the actua-
tor.
3.
Replace the shaft coupling on the opposite side of
the actuator aligning it based on the stroke labeling.
4.
Replace the retainer clip on the shaft coupling using
the groove of the coupling.
Fig. 4. Mounting shaft coupling to actuator
opposite side.
Selecting Actuator Control Signal
(For MS7503 models only)
Selections are made using a dial that appears on both the
front and back of the actuator (see Fig. 5).
To select the control signal simply turn the mode selection
dial to the desired mode (as indicated on the device label)
without exceeding range indicators.
Fig. 5. Dials for control signal.
For MS31XX models only
These actuators are available with Sylk address selection
pot.
NOTE:
There are 5 effective Sylk addresses that you can
choose from. For example, to select Sylk address
11 move the range pot to 1.
Fig. 6. Address selection dial.
Non-Standard Stroke
Mechanical Stroke Limit Reduction
For applications requiring a span less than 95 degrees, a
simple adjustment can be made. When the rotational
mounting of the shaft coupling is changed, the actuator
drives less than the full 95 degrees stroke.
The stroke is adjustable in 7.5 degree increments. Once
adjusted, the actuator drives until the shaft coupling
reaches the mechanical stop (part of the housing). The
stop causes the motor to discontinue driving and the shaft
coupling drives no farther. When the actuator returns, it
stops at the fail-safe position. Mechanical limitation of
minimum position is prohibited. Use electronic or SW
limitation if needed.
To limit the stroke range, proceed as follows:
1.
Remove the retainer clip from the shaft coupling and
set it aside for later use.
2.
Remove shaft coupling from the actuator.
3.
Rotate the coupling to the desired position, aligning
it based on the stroke labeling. See Fig. 7.
NOTE:
The shaft coupling location determines the
travel span.
CCW TO CLOSE
(FAIL-SAFE POSITION)
CW TO OPEN
DAMPER BLADES
M37462
CW TO CLOSE
(FAIL-SAFE POSITION)
CCW TO OPEN
FRONT BACK
M37464
MODE SELECT
1 = 2... 10 VDC
2 = 10... 2 VDC
3 = 0... 10 VDC
4 = 10... 0 VDC
5 = FLOATING (FWD)
6 = FLOATING (REV)
1
2
3
4
5 6
ADDRESS SELECT
1 = ADDRESS 11
2 = ADDRESS 12
3 = ADDRESS 13
4 = ADDRESS 14
5 = ADDRESS 15
6 = TEST
1
2
3
4
5 6
