Honeywell Direct Drive Damper Actuator M847D Installation Guide
- June 7, 2024
- Honeywell
Table of Contents
Direct Drive Damper Actuator M847D
This is a legacy product document supported by Resideo. It is no longer
manufactured
Direct Drive Damper Actuator M847D
APPLICATION
The M847D is a two position, 24 Vac spring return damper actuator designed to
operate directly driven zone dampers, used to control air flow in ducts. The
synchronous motor actuator can be driven open (or closed) using any 24 volt
rated two position switch – e.g. a wall switch or a thermostat subbase switch.
The M847D replaces the RDMH and RDMZ damper actuators for use on Trol-A-Temp®
ARD and ZD dampers.
SPECIFICATIONS
Electrical Rating: 24 Vac 60 Hz 0.32 Amp., 8 VA
Electrical Connection: 1/2″ conduit
Nominal Angular Rotation: 90° (max. 105°)
Torque: Min. 423 mNm (60 in. oz) output torque available when motor is
energized and device is at the spring returned initial start position.
Nominal Motor Timing: ( @ 25° C ambient) Energized at rated load – 30 seconds.
De-energized (spring return) – 10 seconds.
Ambient Temperature Rating: 5 to 60° C (+40 to 140° F)
Finish: zinc plated steel, anodized aluminium
Direction of Shaft Rotation: clockwise, when energized and viewed from the
base or shaft end.
Mounting Means: direct connection to damper shaft.
Mounting Position: Multi-poise.
Dimensions: See Figure 1.
mNm = milli newton meter.
INSTALLATION INSTRUCTIONS
Table 1. Nominal Device Dimension
A
B
C
D
E
F
mm
60
84.5
88
8.2
31.5 19.3
in
2-3/8 3-3/8 3-1/2 5/16 1-1/4
3/4
G
H
J
K
L
M
mm
15.8 58.6 29.3 33.5
6.4
40.4
in
5/8 2-5/16 1-3/16 1-5/16 1/4 1-9/16
Put Bar Code Here 95C-10905-02
DIRECT DRIVE DAMPER ACTUATOR M847D
Fig. 1. Dimensional Details.
INSTALLATION AND CHECKOUT
CAUTION
1. Read these instructions carefully. Failure to follow them could cause a
hazardous condition.
2. Disconnect power supply before beginning of installation and wiring of
control to prevent electrical shock or equipment damage.
3. Check the ratings given in the instructions and on the product to make
sure the product is suitable for your application.
4. All wiring must comply with local electrical codes, ordinances, and
regulations.
5. Installer must be a trained, experienced service technician.
6. After installation is complete, check out the product operation as
provided in these instructions.
3. Observe that the damper blades are in the normal, spring open or spring
closed position.
4. Place the new motor onto the shaft and tighten the coupling.
5. Reconnect the motor wiring.
ALTERNATE MOUNTING (For 7/16″ dia. coupling style dampers) Before installing
the M847D actuator to a damper with a 7/16″ coupling, insert the drive shaft
extension into the drive shaft and tighten with the set screw provided. See
Fig. 2. Also install the anti-rotation extension to the end of the anti-
rotation rod. Install the actuator on the damper and tighten the coupling
screw.
WARNING
1. DO NOT install this actuator on a flue damper. 2. DO NOT attempt to rotate
the actuator by turning
the connection coupling or the damper shaft when it is connected to the
actuator or damage to the gear train may occur.
STANDARD MOUNTING (For 5/16″ dia. damper shaft) The M847D can be attached
directly to the protruding 5/16″ diameter damper shaft using the sleeve of the
output shaft. Drill a 5/16″ (8 mm) hole 1-5/16″ (33.5 mm) directly below the
damper shaft opening to accept the anti-rotation shaft protruding from the
base of the motor. The length of the damper shaft to which the connection
coupling is attached is such as to firmly hold the actuator in a position to
adequately engage the anti-rotation pin in the warm air duct. See Figure 1 for
the critical dimensions.
Replacing M847D on a Trol-A-Temp® ARD damper 1. Disconnect the motor wiring.
2. Using a 1/8 in. hex wrench to loosen the motor coupling from the blade
shaft, remove the existing motor assembly.
Fig. 2. For 7/16″ Coupling Models Only.
Replacing M847D on a Trol-A-Temp® ZDS or ZDB damper 1. Disconnect the motor
wiring. 2. Using a 3/16 in. hex wrench to loosen the Allen screw located above
the faceplate at the motor coupling. 3. Remove the existing motor. 4. Observe
that the damper blades are in the open position with the setscrew pointing
toward the damper label. 5. Attach the new motor to the coupling. Make sure
that the standoff on the motor is positioned in the grommet on the faceplate.
6. Tighten the set screw. 7. Reconnect the motor wiring.
95C-10905–02
2
DIRECT DRIVE DAMPER ACTUATOR M847D
Wiring
See Figure 3 for typical wiring hook-ups of the M847D.
1
24 VAC 60 HZ
ZONING SWITCH
ORANGE
2
YELLOW
OPERATOR MOTOR
1 PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
2 NOMINAL CURRENT 0.32 AMP.
M32381
Fig. 3. Typical M847D Hookup.
CHECKOUT
After completing the installation, check that the equipment operates correctly
as follows:
1. When 24 Vac is applied to the motor leads, the motor powers to the closed
or open position.
2. When power is removed, the motor releases and spring returns to the normal
position.
If full opening and closing is not achieved, check the lower adjustment lever
is to the extreme left and the upper lever is to the extreme right. See Fig. 4
(Air Flow Adjustments).
Air Flow Adjustments
NOTE:
The following describes the adjustments available with the actuator installed in the power closed mode. If the damper you are installing is to operate in the power open mode, the function of the upper and lower levers is reversed.
1. When viewed on end, the lower lever is normally positioned to the extreme
left (See Fig. 4). This position allows the damper to fully open 90° when de-
energized.
2. To restrict the air flow in the open position, loosen (do not removed) the
wing nut and move the lower lever to the right until the desired position is
reached. Tighten the wing nut. In the extreme right position the damper should
open approx. 50° with the power off.
3. The upper lever is normally positioned to the right to provide complete
shut off when the actuator is energized (See Fig. 4).
4. If desired, to prevent complete closure of the damper, loosen (do not
remove) the wing nut on the bottom of the unit and move the upper lever to the
left until the desired position is achieved. Tighten the wing nut. In the
extreme left position the damper should close to approx. 40° with the power
on.
5. If additional rotation is required beyond 90°, an additional 15° may be
obtained by removing the Upper Lever. To do this, first remove the actuator
from the damper. Remove the wing nut and retaining ring then remove the
levers. Reassemble and install.
Fig. 4. Air Flow Adjustment
3
95C-10905–02
DIRECT DRIVE DAMPER ACTUATOR M847D
Automation and Control Solutions Honeywell International Inc. 1985 Douglas Drive North Golden Valley, MN 55422 customer.honeywell.com
® U.S. Registered Trademark © 2010 Honeywell International Inc. 95C-10905–02 T.D. Rev. 12-10 Printed in U.S.A.