Installation Guide
vi MM371W / MM372W Installation Instructions MM371W / MM372W Installation Instructions vii
III. After Installation
1.  Attach the warning signs (included) to each side of the 
gate to alert the public of automatic gate operation. It is 
your responsibility to post warning signs on both sides 
of your gate. If any of these signs or warning decals 
becomes damaged, 
illegible, or missing, replace them immediately. 
Contact Nortek Security and Control for free 
replacements.
2.  The gate is automatic and could move at any time, 
posing serious risk of entrapment. No one should be in 
contact with the gate when it is 
moving or stationary.
3.  Do not attempt to drive into the gate area while the gate 
is moving; wait until the gate comes to a complete stop. 
4.   Do not attempt to “beat the gate” while the gate is 
closing. This is extremely dangerous.
5.  Do not allow children or pets near your gate. Never let 
children operate or play with gate controls. Keep the 
remote control away from children and unauthorized 
users; store controls where children and unauthorized 
users do not have access to them.
6.  KEEP GATE SYSTEMS MAINTAINED. Always turn power 
to operator OFF before performing any maintenance. See 
page 28 for maintenance procedures.
7.  To operate this equipment safely, YOU must know how to 
disconnect the operator for manual gate operation (see 
page iii). If you have read the instructions and still do not 
understand how to disconnect the operator, contact the 
Mighty Mule Service Department.
8.  Disconnect the operator ONLY when the power is 
TURNED OFF and the gate is NOT moving.
9.  Make arrangements with local re and law 
enforcement for emergency access.
10. Distribute and discuss copies of the 
IMPORTANT SAFETY INFORMATION 
section of this manual with all persons 
authorized to use your gate.
11. IMPORTANT: Save these safety instructions. Make sure 
everyone who is using or will be around the gate and 
gate operator are aware of the dangers associated 
with automated gate systems. In the event you sell the 
property with the gate operator or sell the gate operator, 
provide a copy of these safety instructions to the new 
owner. 
Should you need a replacement manual, a copy can 
be obtained by downloading one from the Mighty Mule 
web site (www.mightymule.com), by contacting Nortek 
Security and Control by calling 1-800-543-4283 and 
requesting a duplicate copy. 
FOR THE INSTALLER AND END USER FOR THE INSTALLER AND END USER
Mighty Mule gate operators utilize Dual Sense Technology™ 
entrapment protection. Dual Sense Technology
™ is built 
into every Mighty Mule and provides redundant methods of 
entrapment protection for open and close gate directions.
In addition to Dual Sense Technology, every Mighty Mule 
gate controller has provisions for the connection of 
additional obstruction detection devices such as sensing 
edges and photo beams.
These devices may be located where there is an increased 
risk of obstruction. Refer to the diagram below.   
One or more edge sensors may be located at the leading 
edge, bottom edge, and post edge, both inside and outside 
of a vehicular swing gate system.
Wiring to sensors must be located and arranged so the 
wiring between the sensor and the gate operator is not 
subjected to mechanical damage.
A wireless sensor such as one that transmits radio frequency 
(RF) signals that promote safety shall be located where the 
transmission of the signals is not obstructed or impeded by 
building structures, natural landscaping or similar objects.
Vehicular GateVehicular Gate
Photo Beam
(recommended, not included)
Photo Beam
(recommended, not included)
Sensing Edges
(recommended, not included)
Sensing Edges
(recommended, not included)
Leading Edges
of gates
Gate Warning Sign
Gate Warning Sign
Control Box
Leading Edge
of the gate
Photo Beam
(recommended, not included)
Photo Beam
(recommended, not included)
Sensing Edges
(recommended, not included)
Vehicular Gate
Gate Warning Sign
Control Box
Entrapment and Obstruction Protection 
Mighty Mules’s Dual Sense Technology™ provides entrapment protection. Since all installations are different, you may need to add 
photo beams or sensing edges to help prevent damage to vehicle or other items that could be hit by a moving gate.
Entrapment Alarm
The Mighty Mule Automatic Gate Operator is designed to stop and reverse the gate when the gate comes in contact with an 
obstruction. Additionally, these operators are equipped with an audio entrapment alarm which will activate if the unit obstructs twice 
while opening or closing. This alarm will sound for a period of 5 minutes, or until the operator receives an intended signal from a 
hard wired entry/exit source (e.g. push button control or keypad). Turning the power switch on the control box OFF and back ON will 
also deactivate the alarm. Wireless controls such as transmitters and wireless keypads will not deactivate the alarm.
Important Safety Information Important Safety Information
Example of MM372W Installation
(Installations vary slightly on different types of gates)
Example of MM371W Installation
(Installations vary slightly on different types of gates)
NOTE: Photo beams should 
always be located on the 
non-travel side of the gate.










