
MEP-4201/4501/4901
1
Installation Guide
Installation Guide
Tri-State/Two-Position Actuators (25/45/90 in-lb.)
MEP-4201/4501/4901
Mounting 1
Wiring 2
Maintenance 2
More Information 2
Mounting
Illustration 1—Overview (Direct-Coupled Mounting)
1. Ensure the damper can move freely through its
entire range of motion, and fix any binding before
installing the actuator. Turn the damper blade to
its fully closed position.
2. Press (to the right) and hold the gear disengage-
ment lever (see Illustration 1), rotate the actuator
to the fully closed position, and release the lever.
NOTE: Depending on the damper-seal design,
backing the actuator off its stop
approximately 5° may provide tight
damper shut-off.
3. Align the actuator and slide it onto the shaft.
4. Leaving a gap between the actuator and
mounting surface to prevent any binding, finger-
tighten the nuts on the V-bolt.
5. Insert the provided (HMO-4001/4002, dependent
on model) non-rotation bracket into the slot at the
base of the actuator and secure the non-rotation
bracket with two #8 or #10 self-tapping screws.
6. Evenly tighten the V-bolt nuts (30–35 in-lb.
on MEP-4201 model or 60–70 in-lb. on MEP-
4501/4901).
7. If desired, use a 7/64-inch hex key wrench to
loosen and position the end-stop screw.
NOTE: The two holes at the top of the actuator
are NOT for use in direct-coupled
applications.
(They are for
remote
mounting, such as with the optional
HLO-4001 Crank Arm Kit.)
For mounting
to valves, see the appropriate valve
installation guide.
Gear
Disengagement
Lever
HMO-4002
Non-Rotation
Bracket
Mounting
Surface
1.625
(41.3)
6.000
(152.4)
3.406
(86.5)
Adjustable
Stop
° Rotation
Indicators
1.563
(39.7)
2.812
(71.4)
Gear
Disengagement
Lever
Removeable Conduit Fitting with
(2)1/2" NPS Threaded Holes (for
use with flexible conduit only)
HMO-4001 Non-Rotation “T”
Bracket included with MEP-4901
HMO-4002 Non-Rotation
Bracket included with
MEP-4201& MEP-4501