ML7284 NON-SPRING RETURN DIRECT COUPLED DAMPER ACTUATOR
63-2504—2
4
Disengaging Cycles:
100
CAUTION
Disengaging (pressing manual release button) with
load on actuator can damage actuator gear train.
Approvals:
UL873 (UL94-5V Enclosure: Plenum rating).
UL Listed: File number E4436, Guide number XAPX.
CSA Listed: File number LR95329-17.
Environmental Protection Ratings:
NEMA1 standard with damper shaft in horizontal position.
Accessories:
205617 Hub insert, 3/4 in. round.
205753 Hub insert, 3/8 in.
205758 Hub insert, 5/8 in.
205820A 3-Point Mounting Kit.
205685 Crank-Arm Accessory.
205850C End Stop Kit.
INSTALLATION
When Installing this Product…
1
Read instructions carefully. Failure to follow them could
damage the product or cause a hazardous condition.
2
Check ratings and description given in the
specifications to make sure the product is suitable for
your application.
3
Installer must be a trained, experienced service
technician.
4
After installation is complete, check out product
operation as provided in these instructions.
CAUTION
1.
Disconnect power before installation to prevent
electrical shock or equipment damage.
2.
Never turn motor output hub by hand or wrench
unless declutch button is fully depressed.
3.
Do not install actuator in areas with acid fumes or
other deteriorating vapors that could attack the
metal parts of the actuator.
4.
Do not install actuator in areas with escaping gas
or other explosive vapors that could be ignited by
a spark from the actuator or attached
accessories.
Location
Install the actuator in any location free from acid fumes or
other deteriorating vapors that could attack the metal parts of
the actuator. Make sure the location is not subject to escaping
gas or other explosive vapors that could accidentally be
ignited by a spark from the actuator or its attached parts.
Install the actuator in a location that allows enough clearance
for mounting accessories and for servicing.
Mounting
The ML7284 Non-Spring Return Direct Coupled Damper
Actuator is designed to operate a damper by driving the
damper shaft either cw
or ccw
depending on
damper design. All actuators are shipped in the fully ccw
position.
The ML7284 Non-Spring Return Direct Coupled Damper
Actuator is designed with removable hub inserts to
accommodate specific damper shaft sizes. Proper insert
selection is necessary to avoid excessive strain on the output
gear. Most ML7284 Actuators are shipped with a 1/2 in. hub
insert. For field use, three hub insert sizes are available. See
the Accessories listing in the Specifications section. Shaft
sizes are stamped on the inserts.
The ML7284 Non-Spring Return Direct Coupled Damper
Actuator is designed for single-point mounting when using a
mounting bracket. Single-point mounting is typically used
when the actuator is mounted on the damper shaft.
The ML7284 Non-Spring Return Direct Coupled Damper
Actuator can be mounted directly on the damper shaft with
the actuator in any position.
A mounting bracket (see Fig. 1) is provided with some models
to aid in installing the actuator. The bracket can be bent to
any shape to allow the mounting bracket tab to be centered in
the actuator slot. Install the mounting bracket so that the
mounting bracket tab is centered in the actuator slot.
CAUTION
The mounting bracket must not bind or clamp the
actuator to the duct. The mounting bracket is used to
prevent the actuator housing from rotating.
The ML7284 Direct Coupled Damper Actuator has a
reversible output hub. The hub is factory mounted on the top
of the actuator gear housing. When attaching to damper
shafts lest than 2.5 in. (64 mm) long, or for ease of mounting,
the output hub can be mounted to the back of the actuator
gear housing. See Fig. 3. Be careful when removing the
retaining ring which secures the output hub sleeve to the
actuator housing. Use a flatheaded screw driver to pry the
ring loose. A typical actuator mechanical connection is shown
in Fig. 4; wiring diagrams in Fig. 5 through 8.
The ML7284 Non-Spring Return Direct Coupled Damper
Actuator can also be three-point mounted using the three
frame slots. Three point mounting is used for foot mounting
the actuator or internally mounting the actuator in the duct
when direct shaft coupling is not possible.
CAUTION
Do not use the actuator as a shaft bearing. The
actuator must be used only to supply rotational torque.
To prevent damage to the actuator, avoid any side
loads to the actuator output coupling bearings. Also,
provide clearance for actuator sleeve on the back.