3 NM, 5 NM SERIES SPRING RETURN DIRECT COUPLED ACTUATORS
5 62-0274—07
Actuator Damage Hazard.
Using actuator as shaft bearing causes device 
damage.
Use actuator only to supply rotational torque. Avoid 
any side loads to actuator output coupling bearings.
Equipment Damage Hazard.
Can damage the motor beyond repair.
Never turn the motor shaft by hand or with a wrench.
Forcibly turning the motor shaft can damage the gear 
train.
To mount the actuator to an external drive shaft of a damper, 
proceed as follows:
1. Place actuator over damper shaft; and hold mounting 
bracket in place. See Fig. 7.
2. Mark screw holes on damper housing.
3. Remove actuator and mounting bracket.
4. Drill or center-punch holes for mounting screws (or use 
no.10 self-tapping sheet metal screws).
5. Turn damper blades to desired normal (closed) position.
6. Place actuator and mounting bracket back into position 
and secure bracket to damper box with sheet metal 
screws.
7. Using 10 mm wrench, tighten shaft coupling securely 
onto damper shaft using maximum 240 lb-in. (27.1 Nm) 
torque.
NOTE: See Fig. 6 for proper mounting to a square 
damper shaft.
Fig. 6. Proper mounting to square damper shaft.
Fig. 7. Mounting actuator to damper housing.
WIRING
Electrical Shock or Equipment Damage Hazard.
Disconnect all power supplies before installation.
Motors with auxiliary switches can have more than 
one disconnect.
IMPORTANT
All wiring must comply with local electrical codes, 
ordinances and regulations.
Access Cover Removal (Fig. 8)
Equipment Damage Hazard.
Improper cover removal can damage electric 
connections.
Pull the cover along the axis of the actuator.
The cover contains contact sockets that must connect 
to actuator contact pins.
Bending these pins can permanently damage the 
device.
DAMPER SHAFT
M27717
M27718
ENSURE THAT MOUNTING ASSEMBLY PREVENTS ACTUATOR 
ROTATION AND ALLOWS ACTUATOR TO FLOAT ALONG 
INDICATED AXIS.  WHEN TOO TIGHT, THE RESULTING  BINDING 
CAN DAMAGE THE ACTUATOR OR REDUCE TORQUE OUTPUT.
THE BRACKET CAN BE BENT TO ALLOW MOUNTING THE 
ACTUATOR PARALLEL TO THE MOUNTING SURFACE.
1
PART NO. STRN-BRKT
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2
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