GTO Mighty Mule 352 User Manual

Installation Manual for the

UL325 SERIES

352

®

E-Z GATE OPENER

WARNING!

This equipment is similar to other gate or door equipment and meets or exceeds
Underwriters Laboratory Standard 325 (UL 325). However, gate equipment has
hazards associated with its use and therefore by installing this product the installer
and user accept full responsibility for following and noting the installation and
safety instructions. Failure to follow installation and safety instructions can result
in hazards developing due to improper assembly. You agree to properly install this
product and that if you fail to do so GTO, Inc. shall in no event be liable for direct,
indirect, incidental, special or consequential damages or loss of profits whether
based in contract tort or any other legal theory during the course of the warranty
or at any time thereafter. The installer and/or user agree to assume responsibility
for all liability and use of this product releasing GTO, Inc. from any and all liability.
If you are not in agreement with this disclaimer or do not feel capable of properly
following all installation and safety instructions you may return this product for full
replacement value.

READ ALL INSTRUCTIONS CAREFULLY AND COMPLETELY before attempting to
install and use this automatic gate opener. This gate opener produces a high level
of force. Stay clear of the unit while it is operating and exercise caution at all times.

All automatic gate openers are intended for use on vehicular gates only.

This product meets and exceeds the requirements of UL 325, the standard which regulates gate opener safety,

as established and made effective March 1, 2000, by Underwriters Laboratories Inc.

For more information on Mighty Mule’s full line of Automatic Gate Openers and Access Controls visit our website at www.mightymule.com

GTO Sales: (800) 543-GATE (4283) or [phone] • Fax [phone] or

For 24 hr/day, 7 day/week Technical Service visit http://support.gtoinc.com/support/troubleshooter.aspx

GTO Technical Service [phone] or [phone]

©

2008 GTO, Inc.

rev - 08/08/08

R352INST

The Mighty Mule® Gate Opener is intended for use with vehicular swing gates. The opener can be used in
Class I, Class II and Class III applications.

VEHICULAR GATE OPENER CLASS CATEGORIES

Residential Vehicular Gate Opener-Class I: A vehicular gate opener (or system) intended for use in a

home of one-to-four single family dwelling, or a garage or parking area associated therewith.

Commercial/General Access Vehicular Gate Opener-Class II: A vehicular gate opener (or system)
intended for use in a commercial location or building such as a multifamily housing unit (five or more
single family units), hotel, garages, retail store, or other building servicing the general public.

Industrial/Limited Access Vehicular Gate Opener–Class III: A vehicular gate opener (or system)
intended for use in an industrial location or building such as a factory or loading dock area or other
locations not intended to service the general public.

Conversion Chart

ConvertingMetricUnitstoEnglishEquivalents

When You Know Multiply By To Find Symbol

centimeters 0.3937 inches in. (or ")

meters 3.2808 feet ft. (or ')

kilograms 2.2046 pounds lb. (or #)

ConvertingEnglishUnitstoMetricEquivalents

When You Know Multiply By To Find Symbol

inches 2.5400 centimeters cm
feet 0.3048 meters m
pounds 0.4535 kilograms kg

Converting Temperature

deg. Celsius (ºC x 1.8) + 32 deg. Fahrenheit ºF
deg. Fahrenheit (ºF-32) ÷ 1.8 deg. Celsius ºC

FOR YOUR RECORDS

Please record the product serial number (located on the rear of opener arm),
and the date and place of purchase in the spaces provided below. Refer to this
information when calling GTO for service or assistance with your automatic
gate opener.

Serial Number ____________________ Date of Purchase ____________________

Place of Purchase ____________________

Remember to keep all receipts for proof of purchase.

Table of Contents

Gate Opener Class Categories ------------------------------------------------------------ inside cover
Units and Standards Conversion Chart ------------------------------------------------ inside cover

PLEASE READ THIS FIRST! ------------------------------------------------- page iii

KEEP THESE INSTRUCTIONS FOR FUTURE REFERENCE

Important Safety Instructions ---------------------------------------------- page 1

Disconnecting the Opener ------------------------------------------------------------- page 1
Important Safety Instructions for the Consumer ------------------------------- page 2
Secondary Means of Protection Against Entrapment ------------------------ page 5
Required Safety Precautions for Gates -------------------------------------------- page 6
Warning Signs and Labels ------------------------------------------------------------- page 7

Installation ------------------------------------------------------------------------ page 8

Parts List ------------------------------------------------------------------------------------- page 8
Tools and Items Needed for Installation ------------------------------------------- page 9
Technical Specifications ------------------------------------------------------------- page 10

Installation Overview -------------------------------------------------------------------- page 11

Installation of the Mounting Hardware --------------------------------------------- page 12
Mounting the Master Opener --------------------------------------------------------- page 16

Mounting the Second Opener -------------------------------------------------------- page 16
Installation of the Closed Position Stops ----------------------------------------- page 16
Trench and Lay Conduit for Wiring ------------------------------------------------- page 19

Preparing To Connect The Wires ------------------------------------------ page 19

Attaching Master Battery and Communication Cables ---------------------- page 20
Attaching Second Battery and Communication Cables -------------------- page 21
Powering Options: Transformer or Solar ------------------------------------------ page 22
Connecting the Battery ----------------------------------------------------------------- page 23
Connecting the Transformer ---------------------------------------------------------- page 24
Connecting Solar Panel(s) ------------------------------------------------------------- page 26

Master Control Board Settings -------------------------------------------- page 26

DIP Switches ------------------------------------------------------------------------------- page 26
Dual Mode DIP Switches --------------------------------------------------------------- page 26
Stall Force and Auto-Close ------------------------------------------------------------ page 27

Installing the Receiver ----------------------------------------------------------------- page 28
Setting the Closed Position Limit ---------------------------------------------------- page 29

Setting Your Personal Transmitter Code ------------------------------- page 30

Connecting Additional Safety Devices --------------------------------- page 31

Control Board Connections ------------------------------------------------ page 32

Connecting Accessories ----------------------------------------------------- page 33

Routing Wires Through the Access Panel ----------------------------- page 34

Final Step ------------------------------------------------------------------------- page 35

Push to Open Installation ---------------------------------------------------- page 36

Setting the Open Position Limit -------------------------------------------- page 37

Visual and Audible Diagnostic Indicators ----------------------------- page 39

Repair Service ------------------------------------------------------------------ page 41

Column Installation Information ------------------------------------------ page 42

Accessory Catalog ------------------------------------------------------------ page 43

PLEASE READ THIS FIRST!

®

E-Z GATE OPENERS

Thank you for purchasing a Mighty Mule® 352 E-Z Gate Opener—GTO's "do-it-yourself" automatic gate
opener! When correctly installed and properly used, your Mighty Mule® 352 E-Z Gate Opener will give
you many years of reliable service. Please read the following information and watch the enclosed video to
ensure you have the correct system for your particular needs. Furthermore, this manual and the video will
enable you to properly install your Mighty Mule® 352 E-Z Gate Opener.

The Mighty Mule® 352 E-Z Gate Opener is designed for installation on a pull-to-open dual gate leafs
(gates that open into the property). By purchasing an accessory bracket (FM148), the Mighty Mule®
352 E-Z Gate Opener can accommodate a push-to-open dual gate leafs (gates that open out from the
property). The gates must not exceed 8 feet and 550 pounds or exceed 16 feet and 150 pounds (please
see Technical Specifications on page 10). The Mighty Mule® 352 EZ Gate Opener can be used on vinyl,
aluminum, chain link, farm tube, and wrought iron gates.

Use on solid (surface) gates is not recommended. Solid surface gates have a
high resistance to the wind. If the wind is strong enough, the opener will obstruct
and stop, blow fuses, or may damage the equipment.

The Mighty Mule® 352 E-Z Gate Opener accommodates extra transmitters, digital keypads, solar panels,
push buttons, automatic gate locks, and other access control products. These optional accessories (see
the enclosed Mighty Mule® Accessory Catalog) are available at most stores. Your store should be able to
special order any accessory not in stock. If your store cannot special order accessories, please call the
GTO Sales Department (800-543-GATE).

The Mighty Mule® 352 E-Z Gate Opener features adjustable obstruction sensing. This safety feature
makes the gate stop and reverse direction within 2 seconds when it comes in contact with an obstruction.
MIN is the factory setting; meaning the gate will exert the minimum force on an obstruction before it stops
and reverses direction.

The Mighty Mule® 352 E-Z Gate Opener also has an adjustable auto-close feature. After the gate
reaches the fully open position, it can be set to remain open up to 120 seconds before automatically
closing. Pressing the transmitter button at any time after the gate opens fully will cause it to close
immediately. OFF is the factory setting; meaning the gate will stay open until you press the transmitter (or
keypad, etc.) again.

PLEASE NOTE—If your application requires any of the following:

Slide gates;
Heavy duty or commercial uses;
Professional installation;

please call GTO at (800) 543-GATE [4283] or [phone] for information about our GTO/PRO
professional line of gate openers and accessories. Our Sales Department will be glad to give you the name
and phone number of a GTO/PRO dealer near you.

BEFORE YOU BEGIN TO INSTALL YOUR AUTOMATIC GATE OPENER:

watch the enclosed video and read these instructions carefully and completely
to become familiar with all parts and installation steps. The video is only designed
as an overview of the installation procedure. You must read the installation manual

for detailed instructions on gate opener safety and proper use of the gate opener.

iii

IMPORTANT SAFETY INSTRUCTIONS

Clevis Pin

Hairpin Clip

Gate Bracket

Front Mount

0caVW\U

Because automatic gate openers produce high levels of force, consumers need to know the potential
hazards associated with improperly designed, installed, and maintained automated gate opener systems.
Keep in mind that the gate opener is just one component of the total gate operating system. Each
component must work in unison to provide the consumer with convenience, security, and safety.

This manual contains various safety precautions and warnings for the consumer. Because there are many
possible applications of the gate opener, the safety precautions and warnings contained in this manual
cannot be completely exhaustive in nature. They do, however, provide an overview of the safe design,
installation, and use of this product. CAREFULLY READ AND FOLLOW ALL SAFETY PRECAUTIONS,

WARNINGS, AND INSTALLATION INSTRUCTIONS TO ENSURE THE SAFE SYSTEM DESIGN,
INSTALLATION, AND USE OF THIS PRODUCT.

Precautions and warnings in this manual are identified with this warning symbol. The symbol
identifies conditions that can result in damage to the opener or its components, serious injury, or death.

Because GTO automatic gate openers are only part of the total gate operating system, it is the
responsibility of the consumer to ensure that the total system is safe for its intended use.

To Manually Open and Close the

Gate, Follow the Procedure Below:

CAUTION: The gate will move freely and uncontrolled when the gate
opener is removed from the gate. ONLY disconnect the opener when the
opener power switch is OFF and the gate is NOT moving.

Disconnecting the Opener

1. Turn opener power switch OFF.

2. Remove hairpin clip, clevis pin, and

bushing from the front mounting point.

3. Remove the opener from the mount.

The gate can be opened and closed manually
when the opener is disconnected.

IMPORTANT:

front mount - it will break from the arm weight.

CAUTION: Because the Mighty Mule gate

opener is battery powered, disconnect the opener
ONLY when the power switch on the opener is
turned OFF. Unplugging the transformer does not
turn power to the opener OFF.

NEVER allow opener arm to hang by the

NOTE: Substitute a Pin Lock (FM133) for the clevis pin

on the front mount only of the gate opener to prevent
unauthorized removal of the opener from the gate

(see Accessory Catalog).

Mighty Mule 352

1

IMPORTANT SAFETY INSTRUCTIONS

Gate in the
Open Position

Gate in the
Open Position

ZONE 2

ZONE 3

ZONE 4

ZONE 5

Driveway

ZONE 1

ZONE 2

ZONE 4

ZONE 5

ZONE 3

For The Consumer

WARNING: To reduce the risk of injury or death:

1. READ AND FOLLOW ALL INSTRUCTIONS. Failure to meet the requirements set forth in the instruction
manual could cause severe injury and/or death, for which the manufacturer cannot be held responsible.

2. When designing a system that will be entered from a highway or main thoroughfare, make sure the
system is placed far enough from the road to prevent traffic congestion.

3. The gate must be installed in a location that provides adequate clearance between it and adjacent
structures when opening and closing to reduce the risk of entrapment. Swinging gates must not open
into public access areas.

4. The gate and gate opener installation must comply with any applicable local codes.

I. Before Installation

1. Verify this opener is proper for the type and size of gate, its frequency of use and the proper class rating.

2. Make sure the gate has been properly installed and swings freely in both directions. Repair or replace
all worn or damaged gate hardware prior to installation. A freely moving gate will require less force to
operate and will enhance the performance of the opener and safety devices used with the system.

3. Review the operation of the system to become familiar with its safety features. Understand how to
disconnect the opener for manual gate operation (see page 1).

4. This gate opener is intended for vehicular gates ONLY. A separate entrance or gate must be installed
for pedestrian use (see page 6).

5. Always keep people and objects away from the gate and its area of travel. NO ONE SHOULD CROSS
THE PATH OF A MOVING GATE.

6. Pay close attention to the diagram below and be aware of these areas at all times.

Entrapment Zones for a
Pull-To-Open Application

2

Mighty Mule 352

IMPORTANT SAFETY INSTRUCTIONS

Moving Gate

Area

Moving Gate

Area

Driveway

10'10'

10'10'

10'10'

NEVER INSTALL

any control device

within gray area

Entrapment Zones for a proper Pull-To-Open installation:
Zone 1 – leading edge of the master and second gate.
Zone 2 – between the gate and the gate post.
Zone 3 – the path of the gate.
Zone 4 – the space between the gate in the open position and any object such as a wall, fence, tree, etc.
Zone 5 – pinch points between the opener and gate.

II. During Installation

1. Install the gate opener on the inside of the property and fence line. DO NOT install an opener on the
outside of the gate where the public has access to it.

2. Be careful with moving parts and avoid close proximity to areas where fingers or hands could be pinched.

3. Devices such as contact sensors (safety edges) and non contact sensors (photo beams) provide
additional protection against entrapment.

4. If push buttons or key switches are installed, they should be within sight of the gate, yet located at least
10 feet from any moving part of the gate (see diagram below). Never install any control device where a

user will be tempted to reach through the gate to activate the gate opener.

5. Do not activate your gate opener unless you can see it and can determine that its area of travel is clear of
people, pets, or other obstructions. Watch the gate through its entire movement.

6. Secure outdoor or easily accessed gate opener controls in order to prohibit unauthorized use of the gate.

Pull-To-Open
Application

Mighty Mule 352

3

IMPORTANT SAFETY INSTRUCTIONS

III. After Installation

1. Attach the warning signs (included) to each side of the gate to alert the public of auto matic gate
operation. It is your responsibility to post warning signs on both sides of your gate. If any of these signs
or warning decals become damaged, illegible or missing, replace them immediately. Contact GTO for
free replacements.

2. The gate is automatic and could move at any time, posing a serious risk of entrapment. No one should
be in contact with an activated 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 controls away from children and unauthorized users; store controls where children and
unauthorized users do not have access to them.

6. KEEP GATES PROPERLY MAINTAINED. Always turn power to opener OFF before performing any
maintenance. Clean the push-pull tube with a soft, dry cloth and apply silicone spray to it at least once
per month. Grease hinges, spray push pull tube with high quality silicone spray.

7. To operate this equipment safely, YOU must know how to disconnect the opener for manual gate
operation (see page 1). If you have read the instructions and still do not understand how to disconnect
the opener, contact the GTO Service Department.

8. Disconnect the opener ONLY when the power is TURNED OFF and the gate is NOT moving.

9. Make arrangements with local fire and law enforcement for emergency access.

10. Distribute and discuss copies of the IMPORTANT SAFETY INSTRUCTIONS 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 opener are aware of the
dangers associated with automated gates. In the event you sell the
property with the gate opener or sell the gate opener, provide a copy
of these safety instructions to the new owner.

Additional copies of this manual can be obtained by downloading

one from the Mighty Mule® web site (www.mightymule.com), by
contacting GTO, Inc., at 3121 Hartsfield Road, Tallahassee, Florida
32303 or by calling 1-800-543-4283 and requesting a duplicate copy.
One will be provided to you free of charge.

4

Mighty Mule 352

IMPORTANT SAFETY INSTRUCTIONS

Bottom Edge Contact Sensor

on both sides of the gate

Leading Edge Contact Sensor

on both sides of the gate

Post Edge Contact Sensor

on both sides of the gate

Post Edge Contact Sensor

on both sides of the gate

Vehicular GateVehicular Gate

Secondary Means of Protection Against
Entrapment

As specified by Gate Opener Safety Standard, UL 325 (30A.1.1), automatic gate openers shall have
an inherent entrapment sensing system, and shall have provisions for, or be supplied with, at least one
independent secondary means to protect against entrapment. The Mighty Mule® 352 utilizes Type A, an
inherent (i.e., built-in) entrapment sensing system as the primary type of entrapment protection. Also, the
Mighty Mule® has provisions for the connection of Type B2 protection to be used as the secondary type
of entrapment protection.

1. For gate openers utilizing a contact sensor (e.g., safety edge sensor– Type B2) in accordance with
UL 325 (51.8.4 [i]):

A. One or more contact sensors shall be located at the leading edge, bottom edge, and post edge,

both inside and outside of a vehicular swing gate system.

B. A hard wired contact sensor shall be located and its wiring arranged so that the communication

between the sensor and the gate opener is not subjected to mechanical damage.

C. A wireless contact sensor such as one that transmits radio frequency (RF) signals to the gate

opener for entrapment protection functions shall be located where the transmission of the signals
are not obstructed or impeded by building structures, natural landscaping or similar obstruction.

A wireless contact sensor shall function under the intended end-use conditions.

ENTRAPMENT ALARM (UL 325; 30A.1.1A)

The Mighty Mule® 352 Gate Opener is designed to stop and reverse within 2 seconds when the
gate comes in contact with an obstruction. Additionally, these openers 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 opener receives an intended signal from a hardwired
entry/exit source (e.g. push button control or keypad) and the gate returns to a fully open or fully closed
position. 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.

Mighty Mule 352

5

IMPORTANT SAFETY INSTRUCTIONS

1. KEEP CLEAR! Gate may move at any time.

2. Do not allow children to operate gate or
play in gate area.

3. This gate is for vehicles only. Pedestrians
must use a separate entrance.

Moving Gate Can Cause

Injury Or Death

WARNING

!

Warning SignWarning Sign

Contact Sensor

(

recommended, not included

)

Contact Sensor

(

recommended, not included

)

Pedestrian Gate

Bulldog Pedestrian

Gate Lock

(recommended, not included

)

Vehicular GateVehicular Gate

Contact Sensor

(

recommended, not included

)

Contact Sensor

(

recommended, not included

)

Required Safety Precautions for Gates

Install Warning Signs

Warning signs alert people of automatic gate operation and are required when installing the Mighty Mule®
352 E-Z Gate Opener. Furthermore, a walk-through gate must be installed if pedestrian traffic is expected
near the vehicular gate. We recommend using the GTO Bulldog Pedestrian Gate Lock (Call the GTO
Sales Department) for controlled access.

Entrapment Protection

GTO’s inherent obstruction settings, even when properly adjusted, may not be sensitive enough to
prevent bodily injury in some circumstances. For this reason, safety devices such as safety edge

sensors (or photoelectric sensors), which stop and reverse gate direction upon sensing an obstruction,
are suggested for enhanced protection against entrapment.

Warning Signs

The warning signs (at right) must
be installed on both sides of the
gate (see page 7 for details).

6

Mighty Mule 352

!

Warning signs (4 enclosed) to be installed on each side
of the gate (3–5 feet above the bottom of the gate).

This label is located

under rear mount on the opener.

Logo and warning labels (2) installed on each side of
opener housing.

1-800-543-GATE (4283) • www.mightymule.com

1. KEEP CLEAR! Gate may move at any time.

2. Do not allow children to operate gate or play in gate area.

3. This gate is for vehicles only. Pedestrians must use separate entrance.

Can Cause Injury or Death

MOVING
GATE!

®

E-Z GATE OPENER

UL325 SERIES

®

352

! !

TO MANUALLY OPEN AND CLOSE THE GATE

1. Turn opener power switch OFF.

2. Disconnect front or rear mount from
mounting bracket.

3. Pull opener away from mounting bracket
and move gate.

Disconnect opener ONLY when the power
switch is OFF and the gate is not moving.

Maximum Gate: 550 lbs. (249.4 kg); 16 ft. (4.9 m) • Voltage: 12 Vdc; Frequency: 0Hz; Power: 25W • Class I, II, and III Vehicular Swing Gate Operator

GTO DC SWING Series
Conforms to UL325
5th Edition Standards

Serial No. MM350DUAL-0000000

05/14/08

GTO, Inc. - Ta llahassee, Florida USA

Product identification label

IMPORTANT SAFETY INSTRUCTIONS

These warning labels should be
found at the locations specified
below. If any of them are
missing, immediately contact
GTO for replacements.

Mighty Mule 352

7

Parts List - Opener and Mounting Hardware

Hairpin Clip (4)

3/8" x 1-1/2" Clevis Pin (4)

5/16" x 1-3/4" Bolt (2)

3/8" x 2" Bolt (2)

3/8" x 3" Bolt (4)

3/8" x 8" Bolt (8)

8" Nylon Cable Tie (14)

3/8" Washer (18)

3/8" Lock Washer (14)

5/16" Washer (2)

3/8" Nut (14)

5/16" Nut (2)

Hardware Bag Contents

Second Opener (1)

Master Opener (1)

Post Pivot Bracket (2)

3/8" Bushings (4)

32’ Communication
Cable (1)

Gate Bracket (2)

Post Bracket (4)

Closed Position
Stop Plate (1)

2" Mounting Screw (5)

Installation Video (1)

Customer Support Card (1)

Transformer (1)

Warning Signs (4)

1. KEEP CLEAR! Gate may move at any time.

2. Do not allow children to operate gate or
play in gate area.

3. This gate is for vehicles only. Pedestrians
must use a separate entrance.

Moving Gate Can Cause

Injury Or Death

WARNING

!

Receiver (1)

10’ Master
Battery
Harness (1)

GTO Transmitter (1)

32’ Second Opener
Battery Harness (1)

10’ Master
Battery Harness (1)

8

Mighty Mule 352

Tools Needed

• Center Punch

• Open End Wrenches — 3/8", 7/16", 1/2", and 9/16"

• Small (Flat Bladed) Screwdriver

• Tape Measure

• Level

• Wire Strippers

• Phillips Screwdriver/ Large

• C-Clamps — small, medium, and large

• Power Drill

• 3/8" Drill Bit

• Hacksaw or Heavy Duty Bolt Cutters

• Extra person will be helpful

YOU MAY ALSO NEED THESE ITEMS BEFORE YOU BEGIN THE INSTALLATION
(Some of these items can be found in the Accessory Catalog page 42):

• Low voltage wire (RB509) will be needed to run from the transformer to the opener control board;
length depends upon the distance between the transformer power supply and the opener arm. See
Powering Options: Transformer or Solar on page 22, and the Accessory Catalog.

• If your gate is more than 1000' away from AC power source you will need to use at least one

Mighty Mule® 10 watt Solar Panel (FM123) to charge the 12 Volt automotive or marine type battery
(not included). See the Accessory Catalog.

• If your fence post is made of wood and is less than 6" in diameter or 6" square, see page 12.

• Metal plate or washer between nuts and fence posts to prevent pulling bolts out of wood.

• If your fence post is larger than 6" in diameter you will need threaded rods or carriage bolts longer

than 8". See page 15.

• Low prole ground stop page 17.

• PVC conduit.

• If you have thin walled tube or panel gates, see Recommended Reinforcement Examples on page 12.

• Depending on the type of gate, a horizontal cross member or mounting plate may be needed to
mount the front of the opener and gate bracket to the gate. See page 11, step 2; page 15, step 10.

• Surge protection for transformer.

• Some types of installations require U-Bolts.

• Spade terminal for transformer page 25, step 4.

Mighty Mule 352

9

Technical Specifications

Gate Weight

Gate Length

Number of Cycles Per Day

Mighty Mule 352 Gate Capacity /Cycle Chart

Estimated number of daily cycles, based on use with a transformer and one(1) 12 Volt battery.

550 lbs.
450 lbs.
350 lbs.
250 lbs.
150 lbs.
100 lbs.

50 lbs.

62
67
72
77
82
87
92

5’ - 6’

57
62
67
72
77
82
87

8’

57
62
67
72
77
82

10’

57
62
67
72
77

12’

57
62
67
72

14’

57
62
67

16’

NR
NR
NR
NR

NR
NR
NR

NR
NR

NR

MIGHTY MULE® 352 E-Z GATE OPENER

DRIVE

• Low friction screw drive (linear actuator) rated for -5 ºF to +160 ºF (-21 ºC to +71 ºC).

• Powered by a 12 V motor with integral case hardened steel gear reducer. Motor speed reduced to 260 rpm.

Generates 520 inch lb. of torque at 12 V.

• Maximum opening arc of 110º. Approximate opening time (90º): 18 seconds, depending on weight of gate.

POWER

• The system is powered by a 12 Vdc automotive or marine battery.

• Battery charge is maintained by a 120 Vac, 18 Vac output transformer [rectied to 14.5 Vdc (40 VA) through

the GTO control board] or by optional GTO Solar Panels [the panel should generate minimum of 10 W at
600 mA]. A diode on the control board prevents battery discharge.
IMPORTANT: Never use both transformer and solar panel - this will damage the battery and control board.

• One (1) blade-style control board fuse is rated for 15 A.

NOTE: The transformer should not be directly connected to any battery. Do not replace fuses with

higher ampere rated fuses; doing so will void your warranty and may damage your control board.

CONTROL

• GTO microprocessor-based control board is set for dual leaf, pull-to-open gate installations. DIP switches can

be adjusted to accommodate an optional kit for push-to-open gates (see Accessory Catalog).

• Control board has temperature compensated circuits.

• A circuit on the control board regulates charging. "Sleep draw" is 25 mA; "active draw" is 2 to 5 A.

• Auto-memorization of digital transmitter code.

• GTO remote-mounted RF receiver tuned to 318 MHz.

• Opener length with push-pull tube fully retracted is 37

• Adjustable auto-close timer (OFF to 120 s), and obstruction sensitivity.

• Power terminal bock accommodates a transformer or solar panels.

• DIP switches simplify setup of gate opener.

• Accessory terminal block fully compatible with all Mighty Mule access controls.

• Control board allows connection of safety edge sensors and photoelectric sensors.

• Audio entrapment alarm sounds if unit encounters an obstruction twice while opening or closing.

1

/

4", mounting point to mounting point. Max stroke 19".

OPERATIONAL CAPACITY

• The Gate Capacity Chart shows approximate cycles, per day, you can expect from the Mighty Mule 352 Au-

tomatic Gate Opener when powered with a transformer. Actual cycles may vary slightly depending upon the

type and condition of gate and installation.

NOTE: BALL BEARING HINGES SHOULD BE USED ON ALL GATES WEIGHING OVER 250 LB.
To determine the number of cycles the gate opener will perform using solar panels, please see the specifications

listed on page 22 or call [phone] or [phone] for more information.

* An operation cycle is one full opening and closing of the gate.

10

NOTE: "NR" indicates
this size and weight
combination is not
recommended for the
Mighty Mule 352.

* These specifications are subject
to change without notice.

Mighty Mule 352

32 foot power cable connects
SLAVE to 12 Volt marine or
automotive type battery. (run in
PVC conduit)

32 foot communication cable
allows the MASTER and SECOND
gate openers to operate as an
integrated dual gate system. (run
in PVC conduit)

You will need to trench across the
driveway in order to lay conduit
for the second battery harness
and communication cable.

120 Volt indoor

Transformer

(surge protector

not supplied)

Fence Post
Set in Concrete

Run 1000' (max.) of low
voltage wire to battery
from transformer
(wire not included).

PVC conduit (not included)
to protect wire from lawn
mowers and weed eaters.

Gate Swings Evenly and Freely
Hung Firmly and Plumb

Receiver

Gate Bracket

Master Opener

10'

Battery Harness

Second Opener

Closed Position Positive Stop Plates

Installation Overview

Horizontal Cross Member

Vertical Cross Member

Pull-to-Open Gates (Gate Opens into the Property)

The diagram shown below is an example of a pull-to-open installation on a chain link fence and dual
gate. Mounting the openers on masonry columns requires special procedures; see Column Installation
Information on page 42 if you intend to mount the openers on columns. Furthermore, if you have push-
to-open gates, you will need to purchase 2 push-to-open brackets (FM148) (see Accessory Catalog) to
properly configure your system. See push-to-open installation on page 36 before proceeding.

Preparation of the Gate

Step 1

The gate must be plumb, level, and swing freely
on its hinges. Wheels must not be attached to
the gate. The gate must move throughout its arc

without binding or dragging on the ground.

Note that gates over 250 lb. should have ball
bearing hinges with grease fittings.

Step 2

The fence post must be secured in the ground
with concrete so it will minimize twist or flex
when the opener is activated. We recommend
you position the opener near the centerline
of the gate to keep the gate from twisting and
flexing and to avoid backsplash from rainwater.
The addition of a horizontal or vertical cross
member (if one is not already in place) to provide
a stable area for mounting the gate bracket is
also important.

Mighty Mule 352

11

Thin Walled Tube Gate

Steel Pipe Cut in Half

Gate Bracket

Gate Bracket

Wood or Metal
Reinforcement

Gate Bracket

Panel Gate

1" x 6" Wood Reinforcement

(not supplied)

(not supplied)

Installation of Mounting Hardware

Post 
Bracket

Post 
Pivot Bracket

Metal Plate

Wooden Post

Post
Bracket

Post
Pivot Bracket

Metal Plate

Wooden Post

Center of Gate Hinge

Pull-to-Open Installation

Larger than 6" diameter post

The position of the post bracket determines the leverage and efficiency of the opener. The post bracket
position also sets the clearance between the opener and gate in the open and closed positions (minimum
2 inches for safety reasons).

The curved design of the post bracket works well for installations on round and square fence posts.
Because the post bracket carries the entire thrust of the active opener, bolts that completely penetrate

the fence post must be used.

On wooden posts, place a metal plate or
washer (not supplied) between the nuts
and the fence post to prevent the thrust
of the opener from pulling the bolts and
washers out of the wood.

NOTE: A fence post smaller than 6" in
diameter or 6" square should be made
of metal instead of wood so that it will
remain stable while the opener is moving
the gate.

On round posts of 6" diameter or larger, the post pivot
bracket may not be necessary for the installation. In this
instance, the two post brackets are mounted by themselves.

IMPORTANT:

We strongly recommend using steel pipe, wood or metal to reinforce thin walled tube gates or wood to
reinforce panel gates as shown. These reinforcement methods will prevent damage to the opener and gate
when the opener is installed.

Recommended Reinforcement Examples

12

Mighty Mule 352

Determining the Mounting Position

3/8" x 2" Bolt

3/8" Nut

Post Pivot Bracket

Post Bracket

Post Bracket

3/8" Lock Washer

Post Bracket Assembly

3/8" Washer

Clevis Pin

Hairpin Clip

Post Bracket Assembly

Bushing

Rear Mount

Opener

Clevis Pin

Hairpin Clip

Bushing

Gate Bracket

Front Mount

Level Opener

Fence Post

Gate In Open Position

LEVEL horizontal cross member

Post Bracket Assembly

Gate Bracket

of the Post Bracket Assembly and the Gate Bracket

Step 3

Insert the 3/8" x 2" bolt
through the center hole
of the post brackets
and post pivot bracket
as shown. Fasten a

3

/8" washer, 3/8" lock

3

washer and

/8" nut on
the end of the bolt. DO
NOT overtighten the nut
because the post pivot
bracket will have to be
adjusted later.

NOTE: The following steps are
intended for pull-to-open gate
installations. If you are mounting
your opener on a push-to­open gate (e.g., a gate on a
sloped driveway) you will need
to purchase a Push To Open

bracket (FM148) (see Accessory
catalog). Also, see Push-to-

Open Installation beginning on
page 36.

Step 4

Attach post bracket assembly and gate bracket to the opener with the clevis pins and bushings. Secure the
clevis pins with hairpin clips.

Step 5

With the gate in the open position (up to 110º from its closed position), and the opener fully retracted,

adjust the post bracket assembly and gate bracket until the opener is level. While holding the opener
level, use C-clamps to temporarily keep the post bracket assembly and gate bracket in their respective
positions on the fence post and gate.

Mighty Mule 352

13

Gate in the

CLOSED POSITION

Pinch Area

Gate in the
OPENED POSITION

Pinch Area

2" minimum

2" minimum

Be sure gate opener
and bracket don't bind.

IMPORTANT: While determining the mounting point for the post pivot bracket assembly, be sure that the

position allows for minimum 2 inches of clearance between the gate and the opener in both the open and
closed positions, as shown in the diagrams below. This clearance will give the opener the most efficient
leverage point for opening and closing the gate and more importantly provides the least possible pinch area.

Step 6

After verifying that you have the best position for the post pivot bracket in the open position, insert the
5/16" x 1-3/4" bolt through the aligned holes of the post bracket and post pivot bracket to hold it in place.
Remove the clevis pin from the front mount and while supporting the gate opener, swing the gate and gate
opener to the closed position. With the gate and gate opener in the closed position check the clearance
and be sure that the gate opener is not binding at the post pivot bracket.

If you don't have 2 inches of clearance or the gate opener is binding on the post pivot bracket, remove the

5/16" x 1-3/4" bolt and readjust the pivot bracket until you can achieve these important clearances.

With the post pivot bracket in the optimum position for clearance and freedom of movement, reattach
the opener to the gate bracket in the open position and recheck the gate opener level and make sure the
brackets are clamped securely.

TIP: Turning the pivot bracket over

gives more hole alignment options for
the post pivot bracket assembly. You
can also move the entire post pivot
bracket assembly to different positions
on the gate post to help achieve the
proper clearances.

14

Mighty Mule 352

Installing the Post Bracket Assembly and Gate Bracket

Round Tube & Chain Link Gate

Square Tube Gate

Mounting Plate 
Created for 
Decorative Gate
(required but not
supplied)



Remove excess bolt length 
with hacksaw or bolt cutters

FRONT VIEW

SIDE VIEW

FRONT VIEW

SIDE VIEW

Round Metal Post

Round Wood Post

Square Metal Post

Square Wood Post

Remove excess bolt length 
with hacksaw or bolt cutters

SIDE VIEW

TOP VIEW

EXAMPLES

Post Bracket
Assembly

Mark fence post through 
middle of bracket slots
and drill 3/8" holes

Gate In Open Position

LEVEL horizontal cross member

Mark cross member through middle of
gate bracket slots and drill 3/8" holes

Step 7

Mark reference points for bolt holes on the fence
post through middle of bracket slots. Marking
reference points in this manner allows room for
adjustment when mounting the post bracket
assembly and gate bracket. After marking your
reference points, remove the opener and brackets
from the fence and gate.

Step 8

Drill 3/8" holes into fence post as marked.

Step 9

Fasten post bracket assembly to the fence post

3

using (4)
and nuts (provided). Remove excess bolt length
extending beyond the tightened nuts with a hacksaw
or bolt cutters.

NOTE: In cases where the fence post has a
diameter larger than 6", threaded rods or carriage
bolts longer than 8" (not supplied) must be used.

/8" x 8" bolts, washers, lock washers,

Step 10

Mark reference points for bolt holes on the gate
cross member through middle of gate bracket slots.

Drill 3/8" holes into the gate
cross member as marked.

Mount gate bracket using (2)

3

/8" x 3" bolts, washers, lock
washers, and nuts (provided).
Cut off excess bolt length
extending beyond the
tightened nuts.

Gate Bracket Mounting Examples

Mighty Mule 352

15

Mounting the Master Opener

Level Opener

Gate In Open Position

Post Bracket Assembly
bolted to fence post

Clevis Pin, Bushing, and Hairpin Clip

Clevis Pin, Bushing, and Hairpin Clip

Gate Bracket bolted
to gate cross member

Fence Post

LEVEL horizontal cross member

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Ab]^>ZObSa

5ObS6W\US

0/BB3@G0=F

5ObS6W\US

BVSUObSZSOTQO\]^S\
c^b]Ò[Of

=^bW]\OZ5`]c\RAb]^

PS\SObVUObS

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c^b]Ò[Of

;/AB3@5/B3A31=<25/B3

Step 11

Attach the opener to the securely bolted post bracket assembly and gate bracket using clevis pins, bushings, and
hairpin clips, or optional Pin Locks (see Accessory Catalog). Verify that the opener is level and adjust the post bracket
assembly if necessary.

Mounting the Second Opener

Step 12

Install the second opener on the remaining gate leaf by repeating Step 3 through Step 11, starting on page

13. After you have mounted the second opener, proceed to Installing the Positive Stops.

Installation of the Closed Position Stops

The Mighty Mule® 352 Gate Openers firmly hold the gates in the closed position using
positive stops. The positive stops help stabilize the gate leaves in the closed position.
To further enhance stability and security, we strongly recommended using an optional
Mighty Mule® Automatic Gate Lock (see Accessory Catalog) with your dual gate.

16

Illustration A

Mighty Mule 352

IMPORTANT: You need to

determine which side of the
driveway you will place the battery.
The MASTER gate and gate opener
should be mounted on the same
side as the battery. The gate and
gate opener on the opposite side
of the driveway from the MASTER
and battery will be referred to as the
SECOND gate and gate opener.

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V]`Wh]\bOZZg]\[SbOZ^]abeWbVCP]Zba

A31=<25ObS4`O[S

;/AB3@5ObS4`O[S

B=>D73E

4@=<BD73E

Step 1

Closed Position Stop Plate mounted
on the gate leaf that CLOSES FIRST

Closed Position Stop Plate


Low Profile Ground Stop
in Near the Center of Driveway

FRONT VIEW

SIDE VIEW

Mount Vertically

Attach the horizontal closed position stop plate
to the MASTER gate leaf.

Detach the gate operators from the gates
and move the gates to their closed position
(Illustration A). Using appropriate hardware
for your type of gate (U-bolts for tube or chain
link; screw or bolts for wood or metal - not

supplied) attach the closed position stop
plate (horizontally) about mid height on

the MASTER gate frame. Do not tighten it
completely at this time. Slide the stop plate
toward the frame of the SECOND gate leaf
until they touch (Illustration B). Once you have
moved the stop plate to the correct position,
tighten its hardware completely.

Illustration B

NOTE:

The optional ground stop post is used to provide a secure point for the
SECOND gate to close against. If you will be using the GTO Horizontal Gate Lock
accessory with your gate opener system, the closed position ground stop is REQUIRED,
as shown in Steps 2 and 3.

Step 2

Install a low profile ground stop (not provided)
beneath the SECOND gate stop plate.

The ground stop needs to be positioned near
the end of the gate as shown in Illustration A and
may be made of metal or concrete and should
be firmly secured in the ground (we recommend
setting it in concrete).

Illustration C

Step 3

Attach a vertical closed position stop plate to the SECOND gate.

Using appropriate hardware for your type of gate attach the vertical closed position stop plate to the
SECOND gate frame at the point where it will come in contact with the ground stop post. Do not tighten
it completely at this time. You must slide the closed position stop plate toward the ground stop until they
touch (Illustration C). Once you have moved the stop plate to the correct position, tighten its hardware
completely.

NOTE: For a push-to-open installation (gates open out from the property) attach the closed position stop
plate to the outside of the gate.

Mighty Mule 352

17

Post Bracket Assembly

Gate Bracket

MASTER Gate Opener

Closed Position
Positive Stop Plates

SECOND Gate Opener

OPTIONAL Closed Position
Ground Stop Post

At this stage of the installation, the openers should be installed on the
gate leaves and the open and closed position stops should be in place.

Check List

• The gate is plumb, level, and swings smoothly on its hinges.

• A plate or support was added for the gate bracket (if necessary).

• The openers are level and mounted on the centerline of the gate.

18

Mighty Mule 352

Master OpenerSecond Opener

Trench cut across driveway for
routing of the Communication Cable
and Second Battery Harness Cable.

32 foot Second Battery Harness Cable
and 32 foot Communication Cable
routed through the PVC conduit.

3/4 inch or larger
PVC Conduit

Trench and Lay Conduit for Wiring

Bottom
Access Panel

ON

OFF

ON/OFF
Switch

Step 1

Trench and place 3/4 inch or larger PVC conduit from Master Opener Arm to Second Opener Arm.
At this time you may also choose to trench and lay conduit from an AC power source to the gate for
connecting the 18V transformer.

NOTE: If using solar power, trenching for the transformer is not necessary

Step 2

Route the 32 foot second battery harness cable and 32 foot Communication Cable through the PVC conduit
running from the Second Opener Arm to the Master Opener Arm.

IMPORTANT: After trenching driveway follow these guidelines for PVC installation and running wire.

• DON'T use too many curves in PVC. Use sweeping 90° angles. Wire should be easily removeable if needed.

• DON'T splice wire. This can cause a voltage drop and can interfere with sequencing and the rev counter.

• DON'T run wire in same conduit as AC wiring. This causes communication interference and electrical noise.

• DO use minimum of 3/4" ID (interior diameter) PVC conduit available at your local home improvement store.

Preparing to Connect the Wires

In order to have easy access to the control boards during the rest of the installation,
remove the master and second openers and remount them upside

IMPORTANT:

Return opener arms to the
upright position when installation
is complete to prevent water
damage to the control board.

down.

Mighty Mule 352

19

ON/OFF

C

ontrol Board Access Cover

Control Board

Master Battery
Harness
Connector

Receiver Wires

Communication
Cable (LINK)

ON/OFF Switch

ON/OFF

ON/OFF

ON/OFF

Master

Battery Harness Connector

10 Foot

Battery Harness Cable

Attaching Master Opener Battery and Communication Cables

Conduit

Second
Battery Harness
Cable

Communication

Cable

Master Opener in

Upside Down Position

NOTE: At this point your 32 foot Power Cable and 32 foot Communication Cable should be run
through conduit to connect your master and second.

Step 1

With the MASTER opener mounted in the
upside down position remove the Control
Board Access Panel on the bottom of the
opener arm.

Step 2

Place the 12 Volt automotive or marine type
battery and its weatherproof case within 6 feet
of the fence post where the master opener arm
is mounted.

Step 3

Connect the Communication Cable coming out
of the conduit from the Second Opener to the
LINK terminal on the master opener arm control
board. Be sure to leave enough slack in the
cable to accomodate routing of cable through
access panel.

Step 4

Run the end of the10 foot Master Battery
Harness cable up to the Master Opener and
plug it into the Battery Harness Connector
located in the opener access panel. DO NOT
connect the other end of the Battery Harness
cable at this point.

Step 5

IMPORTANT: Make sure the power switch on
the opener arm is in the OFF position.

20

Mighty Mule 352

ON/OFF

ON/OFF

C

ontrol Board Access Cover

Control Board

Second Battery Harness
Connector (32’)

Communication
Cable (LINK)

ON/OFF Switch

ON/OFF

Master OpenerSecond Opener

Attaching Second Opener Battery and Communication Cables

Step 1

With the SECOND opener mounted in the
upside down position remove the Control
Board Access Panel on the bottom of the
opener arm.

Step 2

Connect the Communication Cable coming
out of the conduit from the Master Opener to
the LINK terminal on the second opener arm
control board. Be sure to leave enough slack
in the cable to accomodate routing of cable
through access panel.

Step 3

Run the end of the Second Battery Harness
Cable up to the Second Opener and plug it
into the battery harness terminal on the control
board. DO NOT connect the other end of the
Battery Harness cable at this point.

Step 4

IMPORTANT: Make sure the power switch on
the opener arm is in the OFF position.

At this point your gate openers should be connected like the picture below.

Mighty Mule 352

21

Powering Options: Transformer or Solar

IMPORTANT:

• The Mighty Mule 352 is designed and intended for use with a 12 Volt automotive or marine type

battery. The battery must be placed inside a weatherproof case and located within 6 feet of the
opener arm. The 10 foot harness supplied connects the battery to the master arm.

• The battery charge is maintained by the 18 Volt transformer included or by using optional solar
panel(s). The transformer or solar panel is connected to the opener arm control board using
low voltage, 16 gauge, dual conductor, multi-stranded, direct burial wire (RB509) (see page 24

and the Accessory Catalog).

• All low voltage wire used with the Mighty Mule® 352 Gate Opener must be 16 gauge dual

conductor, multi-stranded, direct burial wire (see page 24 and the Accessory Catalog). Do not
run more than 1000 feet of wire.

• The transformer is designed and intended for indoor use. If the transformer can be plugged
only into an outside electrical outlet, a weatherproof cover or housing (available at local
electrical supply stores) must be used.

• If your gate is more than 1000 ft. from an ac power source, you will need to use at least one

10 watt Solar Panel to charge the battery (see Accessory Catalog). Refer to the Solar Panels

and Gate Activity chart below.

NEVER USE TRANSFORMER AND SOLAR PANEL(S) AT THE SAME TIME

– it will damage the control board –

Solar Panel and Gate Activity Chart

The table and
map illustrate the
maximum number
of gate cycles to
expect per day in
a particular area
when using from 10

to 30 watts of solar
charging power. (see Accessory
Catalog). The figures shown are
for winter (minimum sunlight) and
do not account for the use of any
accessory items.

Accessories connected to your
system will draw additional
power from the battery and will
require additional solar panels.

Winter Ratings Zone 1 Zone 2 Zone 3

12 v dual gate (10 watts) solar charger 4 8 13
12 v dual gate (15 watts) solar charger 7 13 20
12 v dual gate (20 watts) solar charger 10 18 27
12 v dual gate (25 watts) solar charger 13 23 34
12 v dual gate (30 watts) solar charger 16 28 41

* Use up to 250 feet of 16 AWG
wire to place solar panel in a
good location.

22

Mighty Mule 352

Master Opener

PVC Conduit

BLACK to NEGATIVE

32 ft Second Opener
Battery Harness Cable
run through PVC

10 ft Master Opener
Battery Harness Cable

32 ft Communication Cable

RED to POSITIVE

Connecting The Battery

Attach the 10 foot battery harness wires provided, to the terminals of the battery. Take care to attach the
BLACK wire to the NEGATIVE terminal and the RED wire to the POSITIVE terminal. Reverse connection will
cause damage to the control board.

IMPORTANT: Make sure the power switch on the both opener arms is in the OFF position

Mighty Mule 352

23

Connecting the Transformer

GTO indoor
Transformer

(surge protector

not supplied)

Run 1000' (max.) of low
voltage wire to control
board from transformer

(wire not included).

PVC conduit (not included) to protect
wire from lawn mowers and weed eaters.

Master Opener

IMPORTANT: Never connect the transformer and a solar panel to the opener control board at the same
time. It will damage the control board.

If you are using SOLAR PANEL(S) to charge the opener battery, skip this section and go to "Connecting
Solar Panel(s)" section on page 26.

IMPORTANT INFORMATION ABOUT LOW VOLTAGE WIRE

The only wire acceptable for use with GTO products is 16 gauge multi-stranded, low voltage,
PVC sheathed wire. This particular gauge enables the transformer to provide an adequate
charge through the control board to the battery at distances up to 1000 ft.

DO NOT use telephone wire or solid core wire. Unlike multi-stranded wire, these types of wire

are inadequate for use with your gate opener system. Telephone wire and solid core wire do
not deliver enough voltage for your gate opener to function and will cause the system to go
into a condition known as "low voltage lockout."

NEVER splice wires together. Splicing permits corrosion and seriously degrades the wire's

ability to carry an adequate current.

Step 1

Select the 120 Volt electrical outlet into which you will plug the transformer. Lay the low voltage wire in a
trench following a path from the selected electrical outlet to the control box. Wires coming up from the
ground should be run through PVC conduit to protect them from lawn mowers, weed eaters, and grazing
animals. Be sure to bury the wire laid in the trench.

Step 2

Bring enough wire up through the PVC
conduit to allow for gate movement
from open to closed position. See
example right.

24

Mighty Mule 352

AC@53>@=B31B=@

Transformer

Step 3

Spade Tongue Terminal
(not provided)

1

ON

2 3 4

15

CHARGING
POWER

STATUS

RF

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

OFF 120

MIN MAX

STALL FORCE

CLOSE TIME

SET

LIMIT

LEARN

REMOTE

AUX

OUT

SOLAR
PANEL

18VAC

RCVR

GRN

BLK

RED

EXIT

SAFETY

EDGE

CYCLE

COMMON

LINK

Low Voltage Wire
from Transformer

Master Arm

Control Board

Strip 3/16" off the ends of the low
voltage wire and twist tightly.
Insert these ends to the 18 VAC
terminal block located on the
control board (see illustration at
right). The wires can be inserted
into either terminal regardless of
color. Be certain not to let the

exposed wires touch each other!

Tighten set screws against
exposed end of wires. A dab of
household petroleum jelly on
each terminal will help prevent
corrosion.

Step 4

At the AC outlet strip
the ends of the low voltage wire. Attach these
stripped ends to the transformer terminals.

1

/2" of insulation from

A dab of household petroleum jelly on each
terminal will help prevent corrosion.

We suggest crimping a spade tongue terminal
(not provided) to the end of each wire before
attaching it to the transformer.

Make sure the exposed wires do not touch
each other!

Step 5

Plug the transformer into the electrical outlet.
(Use of a surge protector with the transformer is
strongly recommended - not included) If electrical
outlet is located outdoors, outlet and transformer
should be protected by a weatherproof cover.

Mighty Mule 352

25

1

ON

2 3 4

15

CHARGING
POWER

STATUS

RF

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

OFF 120

MIN MAX

STALL FORCE

CLOSE TIME

SET

LIMIT

LEARN

REMOTE

AUX OUT

SOLAR
PANEL

18VAC

RCVR

GRN

BLK

RED

EXIT

SAFETY

EDGE

CYCLE

COMMON

LINK

1

ON

2 3 4

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

1

ON

2 3 4

15

CHARGING
POWER

STATUS

RF

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

OFF 120

MIN MAX

STALL FORCE

CLOSE TIME

SET

LIMIT

LEARN

REMOTE

AUX
OUT

SOLAR
PANEL

18VAC

RCVR

GRN

BLK

RED

EXIT

SAFETY

EDGE

CYCLE

COMMON

LINK

Low Voltage Wire
from Solar Panel(s)

REDBLK

Connecting Solar Panel(s)

RED

RED

BLACK

BLACK

attach BLACK to negative (–) solar terminal on control board
attach RED to positive (+) solar terminal on control board

Solar Panels connect in PA RALLEL

IMPORTANT: Never connect the transformer and a solar panel
to the opener control board at the same time. It will damage the
control board.

If you are using the transformer included with the Mighty Mule
352 to charge the opener battery, skip this section and go to
"MASTER CONTROL BOARD SETTINGS" below.

3

Strip

/16" off the ends of the low voltage wire from

the solar panel and twist tightly. Attach the RED solar

panel wire to the SOLAR terminal marked (+) and the
BLACK solar panel wire to the SOLAR terminal marked

(–) on the MASTER control board.

Tighten set screws against exposed end of wires. A dab
of household petroleum jelly on each terminal will help
prevent corrosion.

NOTE: For multiple panels wire the panels in parallel as
shown in this diagram.

Master Control Board Settings

DIP Switches

Main DIP Switch Settings (MODES)

DIP Switch #1 - Push/Pull-to-Open

If your gates open into the property the DIP Switch

is set to OFF (factory default). If your gates open out
from the property the DIP Switch must be set to the
ON position. NOTE: if you have a Push-to-Open gate
application you will need Push-to-Open brackets
(see Push-to-Open Instructions on page 36).

MODE 1 MODE 2

DIP #2 DIP #3 Dual Mode Sequence

OFF OFF

ON OFF MASTER opens 1st, SECOND opens 2 seconds later.

OFF ON MASTER opens 1st, SECOND opens 2 seconds later.

ON ON MASTER and SECOND simultaneously open and close.

DIP Switch #4 - Lock/Beacon

This DIP selects the mode of operation of the "AUX OUT" terminal. The OFF (factory) setting is selected

when the Mighty Mule Automatic Gate Lock is used with the Mighty Mule 352. The RED wire from the

lock is connected to the "AUX OUT +" terminal and the BLACK wire from the lock is connected to the

"AUX OUT –" terminal. Factory default-(OFF position provides a timed pulse of voltage to the accessory
while the gate opener is activated). Lock and circuit board will be damaged if #4 is on.

The ON setting is selected when a beacon or light is used with the Mighty Mule 352. One wire from the

low voltage beacon or light is connected to the "AUX OUT +" terminal and the other to the "AUX OUT –"

terminal. (ON position provides a continuous voltage to the accessory while the gate opener is activated).

Important: Make sure your light or beacon is a 12Vdc system that draws less than 2 amps or less than 25 watts.

26

Single Gate Mode

SECOND closes 1st, MASTER closes 4 seconds later. (factory)

SECOND closes 1st, MASTER closes 8 seconds later.

Mighty Mule 352

1

ON

2 3 4

CHARGING
POWER

STATUS

RF

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

OFF 120

MIN MAX

STALL FORCE

CLOSE TIME

SET

LIMIT

LEARN

REMOTE

SOLAR
PANEL

18VAC

RECR

GRN

BLK

RED

EXIT

SAFETY

EDGE

CYCLE

COMMON

LINK

OFF 120

CLOSE TIME

1

ON

2 3 4

RF

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

OFF 120

MIN MAX

STALL FORCE

CLOSE TIME

SET

LIMIT

LEARN

REMOTE

RECR

GRN

BLK

RED

SAFETY

EDGE

CYCLE

COMMON

MIN MAX

STALL FORCE

15

STAT

MIN

MAX

STALL FORCE

SET

LIMI

Stall Force Potentiometer Setting

IMPORTANT: For safety reasons the obstruc-
tion setting or Stall Force on the Mighty Mule®
352 control board comes from the factory set at
MIN (minimum). In many gate installations this
setting will need to be adjusted to overcome the
weight and size of the gates.

The Stall Force potentiometer on the con­trol board operates like a volume control on a
radio. It controls the obstruction sensitivity (or
the amount of force the opener will apply to an
obstruction) before it automatically stops and
reverses direction for approximately two (2)
seconds.

Use a small slotted screwdriver to turn the arrow
in the center of the potentiometer. Adjust the
sensitivity from the MINIMUM position where the
gate operates without obstructing from its own
weight or the wind conditions in your area.

NOTE: You may need to increase the
stall force in cold weather due to increased
resistance from gate hinges.

ALWAYS KEEP SAFETY AT THE TOP OF YOUR LIST WHEN ADJUSTING OR

SERVICING YOUR AUTOMATIC GATE OPENER!

Setting Auto-Close Time

MASTER ARM CONTROL BOARD ONLY

CLOSE TIME (auto close timer): Determines how long

the gate will remain open before it automatically closes.
The limits are OFF to 120 seconds. The factory setting
is the OFF position.

Note: Gate will NOT automatically close unless both
gates are at the fully open position regardless of the
auto-close timer setting.

MASTER

Control Board

SECOND

Control Board

Mighty Mule 352

27

Installing the Receiver

Use the transmitter to check the range of the receiver before permanently mounting it.

Consider the following when mounting the receiver:

• Standard receiver cable length is 10 feet (receivers with a longer cable are

available as special order items; call the GTO Sales Department). NEVER splice
receiver cable!

• Run the cable through PVC conduit to protect it from damage.

• DO NOT run cable through metal conduit because the receiver signal range will

be decreased.

• DO NOT coil excess cable or store it in the control box.

• DO NOT run cable in conduit containing ac wiring.

• The receiver range can vary from 50 to 100 feet depending upon weather,

topography, and external interference.

NOTE: Do not mount upside down.

FCC Regulation

This device complies with FCC rules Part 15. Operation is subject to the
following conditions:

1. This device may not cause harmful interference.

2. This device must accept an interference that may cause undesired
operation.

Transmitter distance may vary due to circumstances beyond our control.

NOTE: The manufacturer is not responsible for any radio or TV
interference caused by unauthorized modifications to this equipment.
Such modifications could void the user’s authority to operate the
equipment.

28

Mighty Mule 352

Fully Open Position

Fully Closed Position

Setting the Closed Position Limit

1

ON

2 3 4

CHARGING
POWER

STATUS

RF

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

OFF 120

MIN MAX

STALL FORCE

CLOSE TIME

SET

LIMIT

LEARN

REMOTE

SOLAR
PANEL

18VAC

RECR

GRN

BLK

RED

EXIT

SAFETY

EDGE

CYCLE

COMMON

LINK

SET LIMIT Button

MASTER CONTROL BOARD

SET LIMIT Button

SECOND CONTROL BOARD

15

STATUS

MIN

MAX

STALL FORCE

SET

LIMIT

LINK

ON/OFF

* NOTE: You may need to set the stall force slightly off of minimum
depending on the size and weight of the gate.

For PULL-TO-OPEN Installation
Turn the power switches on the
opener arms to the ON position

Your Mighty Mule 352 has two Limit Settings

1) OPEN Limit setting: (gates in the OPEN POSITION /
FACTORY SET & NOT ADJUSTABLE) The open limit setting
is the fully open position. At this point the arms are

fully retracted.

2) CLOSED Limit setting:

The CLOSED Limit setting (gates in the CLOSED POSITION)
To achieve optimum closed position, you are required to complete

the following FOUR STEPS:

Step 1

While programming, be sure the gate is in the OPEN POSITION and
the operator is mounted upside-down with “SET LIMIT" PROGRAM
BUTTON visible on the control board.

Step 2

Activate your opener by pressing the entry transmitter. Your gates
should now be moving from the fully open position toward the
closing position. Press the transmitter again to stop the gate at the
desired closed position. Note: whichever gate reached its desired
closed position first that will be the first one to be programmed.

• If the second arm is stopped at the desired closed position,
press the 'SET LIMIT' on the SECOND ARM for 5 seconds.

• If the master arm is stopped at the desired closed postion,
press the 'SET LIMIT' on the MASTER ARM for 5 seconds.

Step 3

Save the setting by pressing the transmitter and allowing the gate to
return to the fully open position. YOUR CLOSED POSITION LIMIT IS
NOW PROGRAMMED.

Step 4

Repeat step 2-3 for the other arm that has not been programmed in
step 2.

TESTING YOUR CLOSED LIMIT SETTING:

Press your entry transmitter and allow your gate to close. If CLOSED
position is not correct or needs to be changed you will need to CLEAR
your CLOSED LIMIT (see below) setting and follow steps 1 through 3
again.

CLEARING PROGRAMMED CLOSED LIMIT SETTING:

If you make a mistake and set the limit at the wrong position – press your
transmitter to return the gate to its fully opened position, then press and
hold the "SET LIMIT" button on the corresponding arm for 5 seconds. This
will clear the memory for the closed limit position. Follow Steps 1-3 again.

Mighty Mule 352

29

1

ON

2 3 4

CHARGING
POWER

STATUS

RF

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

OFF 120

MIN MAX

STALL FORCE

CLOSE TIME

SET

LIMIT

LEARN

REMOTE

SOLAR
PANEL

18VAC

RECR

GRN

BLK

RED

EXIT

SAFETY

EDGE

CYCLE

COMMON

LINK

LEARN REMOTE
Button

Master Arm

Control Board

Setting Your Personal Transmitter Code

+

0

ECE

1 2 3 4 5 6 7 8 9

1 2 3 4 5 6 7 8 9

ECE

A23S 12V

ALKALINE BATTERY

+

0

–

LED

All GTO transmitters are set to a standard code at the factory and are ready to operate your Mighty Mule®
352 Gate Opener

®

. For your safety and security, however, we strongly recommend that you replace the

factory setting with your own personal code. Follow the directions below:

1. Remove the Transmitter Cover

On the back of the transmitter use a small phillips head screw driver
to remove the two screws on the sides of the visor clip and separate
the front cover from the transmitter. With the front cover removed,
the battery and the DIP switches will be exposed. To set a new code,
use a small screwdriver to move the switches.

2. Set the transmitter DIP Switches

There are nine (9) transmitter DIP switches; each can be placed in three
different positions (+, 0, –). DO NOT set all the switches in the same
position, such as all +, all 0, or all –. Once the DIP switches have been set to
a personal code, replace and close the access cover.

WARNING: No other adjustments should be made inside the transmitter.

3. “Teach” the New Code to Control Board Memory

A. Press and hold transmitter button.
B. Press and hold the LEARN REMOTE button on
the control board until it beeps.
C. Release transmitter button.
D. Release LEARN REMOTE button. The new code
is stored in control board memory.

30

Mighty Mule 352

Connecting Additional Safety Devices

Although GTO strongly recommends the use of additional safety devices, we do not endorse any

specific brand names. Only use products that are certified and listed to be in compliance with any

applicable UL standards (Underwriters Laboratories) and national and regional safety codes.

Call GTO Sales at 1-800-543-4283 for information on compatible

products for your specific application.

Mighty Mule 352

31

3

1

6

4

5

7

8

9

10

1ON2 3 4

15

CHARGING

POWER

RF

PULL-PUSH

MODE1

MODE2

LOCK/BEACON

OFF 120

MIN MAX

STALL FORCE

CLOSE TIME

SET

LIMIT

LEARN

REMOTE

AUX

OUT

SOLAR

PANEL

18VAC

RCVR

GRN

BLK

RED

EXIT

SAFETY

EDGE

CYCLE

COMMON

LINK

2

Control Board Connections

1 AUX OUT (+): (Typically for use with automatic gate lock or light)

• Provides 12Vdc power @ a maximum of 2 Amps or less than 25 watts when the gate is in motion.

2 AUX OUT (-): (Typically for use with automatic gate lock or light)

LOCK OUTPUTSCHARGE POWER INPUTSACCESSORY INPUTS

• Provides 12Vdc power @ a maximum of 2 Amps or less than 25 watts when the gate is in motion.

NOTE:

• Allcontrolinputsaredry-contact,normallyopen,inputs.DONOTapplyexternalvoltagesourcestotheseinputs.

 • AllinputsareconnectedwithrespecttoCOMMON terminal.
 • Thestatuslightwillblinkoncewhenitscorrespondinginputisactivated.

3 SOLAR PANEL (-)

  • Input for 18-22Vdc charge power from solar panel

4 18 VAC

• Input for 18-22Vac charge power from transformer

5 SOLAR PANEL (+):

  • Input for 18-22Vdc charge power from solar panel

• Input for 18-22Vac charge power from transformer.

6 EXIT: (Typically for use with exit loop or wand)

• Activation of this input will open the gate if it’s not already at

the open position

• Activation of this input while at open limit will restart the auto

close time (if enabled).

7 SAFETY: (Typically for use with photo beam device, loop
detector or other non-contact sensors)

• Activation of this input while the gate is closing will cause

the gate to stop and return to the opened position.

• Activation of this input while the gate is opening has no effect

(gate will continue to open).

• Activation of this input while gate is idle will prevent gate from

closing.

8 EDGE: (Typically for use with safety edge device or other
contact sensor)

• Activation of this input while the gate is operating will cause the

gate to stop and reverse direction for approximately 2 seconds.

• Activation of this input while gate is idle will prevent gate

from opening or closing.

9 CYCLE: (Typically for use with doorbell button or hardwired keypad)

• Each activation at this input will cycle the operation as follows:

….→ OPEN → STOP → CLOSE → STOP → OPEN → …

10 COM: Circuit common (reference for all logic input)

• Two (2) terminals to provide extra common connection point.

32

Mighty Mule 352

CHARGING
POWER

RF

AUX

OUT

SOLAR
PANEL

18VAC

RCVR

GRN

BLK

RED

EXIT

SAFETY

EDGE

CYCLE

COMMON

LINK

GTO Photo Beams

GTO Loop Detector

GTO
Automatic Lock

Mighty Mule
Push Button Control

According to
Application

Mighty Mule
Vehicle Sensor

Refer to Vehicle Sensor
manual for additional
connections.

Edge Sensor

ON

1 2 3 4 5 6 7 8 9 10

DIP

NO
COM
NC
V +
V –
LOOP
LOOP

LOOP

NOTE: Connections are
for typical applications.
There may be additional
connection options for
applications that are not
illustrated here.

8

10

10

1010

7

10

6

Mighty Mule
Keypad

GTO Universal Receiver

6

7

9

10

1

2

ABC

3

DEF

4

GHI

5

JKL

6

MNO

7

PRS

8

TUV

9

WXY

0

8

1 2 3 4 7 8 9 105 6

1

10

10

10

1

1

1

10

10

Ch 2 Wireless Wand

Ch 1 Remotes

Red

Blue

Black

Shield

Yellow

Red + Power

Black - Power

6

9

10

AUTOMATIC
GATE LOCK

®

ELECTRONIC SECURITY LOCK

2

1

NOTE: When
connecting Automatic
Lock make sure
DIP #4 is set to off.

Connecting Accessories

Mighty Mule 352

33

ON/OFF

– o

Battery Harness Wires

Transformer or Solar Wires

Receiver Wires

Communication Cable (LINK)

Accessory Wires

Neatly arrange all
wires to lay flat as
they come out of
the opener.

Mighty Mule 352
Master Opener
Wire Routing

Routing Pin

20 amp fuse

20

Wire Slot

To avoid stripping screw
holes - tightening screws
by hand with a hand held
screwdriver is recommended.

ON/OFF

– o

Battery Harness Wires

Communication Cable

Neatly arrange
both wires to lay
flat as they come
out of the opener.

Mighty Mule 352
Second Opener
Wire Routing

Routing Pin

Routing Wires Through The Access Panel

Master Opener

The master opener's battery harness wire has an in-line 20 Amp fuse

that must be placed inside the opener prior to closing the access
panel. The illustration to the right shows the best place­ment for the battery harness wire, connector and in-line
fuse, communication cable, receiver wire, transformer
or solar panel and any accessories that have been
installed. All wires must be routed down the sides of the
opener and flatly out the slot in the back of the opener.

It is IMPORTANT that the wires lay flat and run inside the
routing pins at the back of the opener and out the slot
without being pinched when the control board access
cover is replaced. See the illustrations to the right and
below.

Second Opener

The battery harness and
communication cable must be
routed down the sides of the opener
and flatly out of the slot in the back
of the opener.

It is IMPORTANT that the wires lay
flat and run inside the routing pins
at the back of the opener and out
the slot without being pinched when
the control board access cover is
replaced. See the illustrations to the
right and below.

34

If you have any questions please
call GTO Technical Service at

1-800-543-1236.

Mighty Mule 352

Final Step

When everything has been connected to the opener...

Replace the control board access
cover. If you were working with the
opener with the control board access
facing up, remove the opener arm
from both mounts and remount
it in the upright position (control
board cover facing down). Failure
to remount opener in the up right
position will allow water to enter the
opener and cause damage to the
opener control board.

Mighty Mule 352

35

Gate in the Closed Position

Pinch Area (gray)

Gate in the Open Position

Pinch Area (gray)

2" minimum

2" minimum

Push to Open Installation

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!&<cb

>caVB]=^S\0`OQYSb
]^bW]\OZOQQSaa]`g

>]ab0`OQYSb

>]ab0`OQYSb

!&:]QYEOaVS`

Post Bracket Assembly

!&EOaVS`

Determining The Mounting Position
of The Post Bracket Assembly

Swinging gates shall not open into public access areas!

"Push-to-Open" gates open out from the property.

Push-to-Open Brackets are required for this type of
installation (see Accessory Catalog). If you have pull-to-open

gates (gate opens into the property), return to page 13; step 3.

In a PUSH-TO-OPEN installation the opener is installed while
the gate is in the closed position.

Step 1

With the gate in the closed position (up to 110º from its

open position), and the opener fully retracted, adjust
the post bracket assembly and gate bracket until
the opener is level. While holding the opener level,
use C-clamps to temporarily keep the post bracket
assembly and gate bracket in their respective positions
on the fence post and gate.

IMPORTANT: While determining the mounting point for the

post pivot bracket assembly, be sure that the position allows for
minimum 2 inches of clearance between the gate and the opener
in both the open and closed positions, as shown in the diagrams
below. This clearance will give the opener the most efficient
leverage point for opening and closing the gate and more
importantly provides the least possible pinch area.

Step 2

After verifying that you have the best
position for the post pivot bracket, insert the

5

/16" x 1 3/4" bolt through the aligned holes

of the post bracket and post pivot bracket
and fasten it with the 5/16" washer and nut.

IMPORTANT: If you loosened the clamp on
the post bracket to achieve the optimum
position, tighten it in its new position and
recheck the gate bracket with the gate in
the open position (move the gate bracket
and re-clamp it if necessary).

36

Mighty Mule 352

Step 3

Operator

Fence Post

Gate Post and Gate Cross Member
(In Closed Position)

POST PIVOT BRACKET level with the
horizontal surface of the GATE BRACKET

LEVEL

LEVEL

LEVEL

1

ON

2 3 4

15

CHARGING
POWER

STATUS

RF

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

OFF 120

MIN MAX

STALL FORCE

CLOSE TIME

SET

LIMIT

LEARN

REMOTE

AUX OUT

SOLAR
PANEL

18VAC

RCVR

GRN

BLK

RED

EXIT

SAFETY

EDGE

CYCLE

COMMON

LINK

1

ON

2 3 4

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

With the gate in the fully closed position and the opener retracted, swing the opener to the gate. Mark
reference points for bolt holes on gate cross member through middle of gate bracket slots. The opener
must be level. (Some vertical adjustment is possible by sliding the post bracket assembly up and down.)

Drill 3/8" holes into the gate cross member as marked. Fasten gate bracket to cross member using (2)
3/8" x 3" bolts, washers, lock washers, and nuts. Attach the opener to the post bracket assembly and gate
bracket using clevis pins, bushings, and hairpins clips.

Step 4

Make sure the control box power switch is OFF. Use a small
screwdriver to move the Number 1 DIP switch from the factory
setting (OFF / Pull-To-Open) to ON for Push-To-Open. Turn
power switch ON. The control board is now configured to
push the gate open.

Setting the Open Position Limit

Step 1

Confirm that the power switch is in the ON position, and the gate is in the CLOSED POSITION.

Step 2

Activate your opener by pressing the entry transmitter. Your gates should now be moving from the fully
CLOSED POSITION toward the opening position. Press the transmitter again to stop the gate at the desired
OPEN position. Note: whichever gate reached its desired open position first that will be the first one to be
programmed.

• If the second arm is stopped at the desired open position,

press the 'SET LIMIT' on the SECOND ARM FOR 5 SECONDS.

• If the master arm is stopped at the desired open postion,

press the 'SET LIMIT' on the MASTER ARM FOR 5 SECONDS.

Mighty Mule 352

37

Step 3

1

ON

2 3 4

CHARGING
POWER

STATUS

RF

PULL-PUSH
MODE1
MODE2
LOCK/BEACON

OFF 120

MIN MAX

STALL FORCE

CLOSE TIME

SET

LIMIT

LEARN

REMOTE

SOLAR
PANEL

18VAC

RECR

GRN

BLK

RED

EXIT

SAFETY

EDGE

CYCLE

COMMON

LINK

SET LIMIT Button

SET LIMIT Button

SECOND CONTROL BOARD

15

STATUS

MIN

MAX

STALL FORCE

SET

LIMIT

LINK

Save the setting by pressing the transmitter and allowing the gates
to return to the fully closed position. YOUR OPEN POSITION LIMIT
IS NOW PROGRAMMED.

Step 4

Repeat step 2-3 for the other arm that has not been programmed
in step 2.

TESTING YOUR OPEN LIMIT SETTING:

Press your entry transmitter and allow your gate to open. If OPEN
position is not correct or needs to be changed you will need to
CLEAR your OPEN LIMIT (see below) setting and follow steps 1
through 3 again.

CLEARING PROGRAMMED OPEN LIMIT SETTING:

If you make a mistake and set the limit at the wrong position – press
your transmitter to return the gate to its fully closed position, then
press and hold the "SET LIMIT" button for the corresponding arm for
5 seconds. This will clear the memory for the open limit position.
Follow Steps 1-3 again.

38

Mighty Mule 352

Visual and Audible Diagnostic Indicators

If your gate opener does not function properly after it is installed, use this guide or use the online

troubleshooter at http://support.gtoinc.com/support/troubleshooter.aspx before calling the

GTO Service Department.

• On all gates weighing 250 lb. or more, routinely grease the ball bearing hinges at least 4 times a year;

more frequently if the gates are in a coastal area.

• Clean the push-pull tube with a soft, dry cloth and apply silicone spray to it at least once a month.

• While oxidation is a normal part of weathering of equipment that is exposed to the elements, we

recommend you apply silicone spray the front and rear mounts to minimize this effect.

Audible/Buzzer/Alarm Feedback:

1. 1 beep with 2 seconds off:

Limit switch error: Limit switch’s normally open and normally close inputs both open or both shorted.
Circuit board is indicating faulty limit switch inside the operator. The alarm will automatically shut off in
4 seconds after the problem is corrected. Call Tech Support.

2. 5 beeps with 2 seconds off:

Low battery condition detected:

- Check battery voltage to ensure you have 12.5 to 13.5 Vdc

- Check transformer output to ensure you have 18-22 Vac

- Check charging circuit with transformer or solar panel connected to ensure battery is being charged to

13.8 to 14.8 vDC. Battery may be charged with a trickle charger at 12Vdc 2 amps for 3 to 4 hours but
be sure to disconnect it from the system.

3. 1 beep when attempt to run the unit:

- Blown fuse

- Dead cell or extremely low battery condition.

- Bad connection from battery to circuit board.

4. Alarm continuously beeps (remote does not operate unit AND not at either limits):

- Two consecutive obstructions have been detected without reaching the limit. Alarm
will automatically shut off after 5 minutes. ‘Power-cycle’ the unit will also shut off the alarm.

- The battery may be extremely low.

5. Learn Remote: (MASTER ARM ONLY)

When a new code is learned from the remote the alarm will sound. Release the ‘LEARN REMOTE’ button
will turn the alarm off. See "Setting Your Personal Transmitter Code" section on page 30.

6. Power-Cycle:

The alarm will beep for 1 second upon power up to indicate the opener is ready to operate.

Visual/LEDs Feedback:

1. RF LED (LED2): (MASTER ARM ONLY)

Blinking when there is 318 MHz signal is received. This LED is typically off when the receiver is connected
and no 318 MHz signal is presented.
If no light:
a. Check receiver connection on the control board
b. Replace the battery in the remote.
c. Relocate antenna

d. Re-learn the remote

Mighty Mule 352

39

2. STATUS LED (LED1):

While the unit is IDLE:

1 blink with 2 seconds off:

Free Exit terminal is shorted to common. Check exit wand or loop detector.

2 blink with 2 seconds off:

Safety terminal is shorted to common. Check photo beams or loop detector.

3 blink with 2 seconds off:

Edge terminal is shorted to common. Check edge sensor.

4 blink with 2 seconds off:

Cycle terminal is shorted to common. Check push button, wired keypad or wired intercom.

LEARN LIMIT Mode:
This LED will turn on when the ‘SET-LIMIT’ button is pressed. It will turn off after 3 seconds

indicating that it has entered the learn limit mode (if not at the retracted limit) or cleared the
previous learned limit (if at retracted limit). See "Setting Closed Position" section on page 27.
Whenever there is a change in state at any of the inputs this LED will blink once.

3. POWER LED (Green): (MASTER ARM ONLY)

ON: AC power or solar power is present.
OFF: NO AC power or solar power is present.

4. CHARGING LED (Red): (MASTER ARM ONLY)

Continuously ON: Fast charging mode. (~1.5 Amps charging current). 14.8 Vdc Blinking (two blinks per
second): Soak charge. Enter this mode after fast charging. The battery is almost at full charge in this
mode. 14.2 Vdc Slow blinking (one blink per second): Float charge. In this mode when the battery is

fully charged. 13.8 Vdc

The Gate CLOSES Then Opens Again on its Own:

1. Check the position of the pivot and post brackets and readjust if necessary.

2. Check the gate for binding or hinge damage.

3. Reset closed position limit.

4. Adjust stall force.

The Gate OPENS Then Closes Again on its Own:

1. Check the position of the gate brackets and readjust if necessary. Take opener off gate. Retract tube
with remote. Re-attach arm to see if hole in front mount aligns with hole in gate bracket.

2. Check the gate for binding or hinge damage.

3. Adjust stall force.

VOLTAGE RATINGS

18 Vac Transformer _________________________ 18.0 to 22.0 Vac

10 W Solar panel (single) ____________________18.0 to 22.0 Vdc 600 mA
measure voltage at panel and control box.

12 V Battery ________________________________12.5 to 13.5 Vdc

Charging circuit ____________________________ 13.8 to 14.8 Vdc
measure voltage with battery connected

40

Mighty Mule 352

Repair Service

®

E-Z GATE OPENERS

If your Mighty Mule® 352 Gate Opener is not operating properly, please follow the steps below:

1. First use the procedures found in the Visual and Audible Diagnostic Indicators section (see page 39).

2. Use the Online Troubleshooter at http://support.gtoinc.com/support/troubleshooter.aspx.

3. If you are unable to solve the problem, call the GTO Service Department at [phone], or
[phone]. Refer to the serial number (located on the back of opener arm) and date of purchase
when calling for assistance.

4. If repair or replacement of your gate opener is necessary, the Service Department will assign a
Return Goods Authorization (RGA) number to you for all warranty repairs

5. Securely pack the component(s) authorized for return to the factory. Include a copy of your receipt for
proof of purchase. Write the RGA number issued to you on the outside of the package in
LARGE BOLD PRINT. Ship the package(s) freight prepaid to:
GTO, Inc., 3121 Hartsfield Road, Tallahassee, Florida, USA 32303.

NOTE: Products returned to GTO without a Return Goods Authorization (RGA) number in
LARGE BOLD PRINT on the outside of the package WILL NOT be accepted. Also, items
returned to GTO freight collect WILL NOT be accepted.

For more information on Mighty Mule’s full line of Automatic Gate Openers and Access Controls visit our website at www.mightymule.com

For 24 hour/day, 7 day/week Technical Service visit

http://support.gtoinc.com/support/troubleshooter.aspx

The GTO, Inc. Technical Service Department is open

Monday – Friday 8:00 A.M. – 7:00 P.M. (Eastern Time)

1-800-543-1236

For sales call toll free:

1-800-543-GATE (4283)

GTO, Inc.

3121 Hartsfield Road • Tallahassee, Florida, USA 32303 • [phone]

Fax [phone] • www.mightymule.com

Mighty Mule 352

41

Column

Pivot Bracket

Gate

A

B

Column Mount Example

(A + B can not exceed 14 inches)

Example: If A is 2" then B can not exceed 12"

Hinge

Column Installation Information

IF THIS OPENER WILL BE USED WITH GATES THAT ARE MOUNTED ON

MASONRY, BRICK, OR ROCK (etc.) COLUMNS:

READ THE FOLLOWING CAREFULLY BEFORE PROCEEDING

A. The simplest solution is to install the opener in a push-to-open configuration (requires Push-To-

Open Bracket, see Accessory Catalog). The minimum clearance is easier to achieve and clearance
is no longer a problem, since the opener will be pushing the gate away from the column instead of
pulling it toward the column. It is recommended that you place a steel plate between the opener
mounting brackets and masonry surface for additional strength.

B. If a push-to-open installation is impossible due to traffic hazards, terrain, etc., another option is

to re-hang the gate. You may hang it on a post, either in the center of the column or at the back
corner, or move the gate to the back corner of the columns.

C. The most difficult solution is to cut a notch in the column to accommodate the opener and power

cable. This job is NOT for the inexperienced!

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Mighty Mule 352

®

E-Z GATE OPENERS

ACCESSORIES

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Accessories are Available From Your Retail Store

Solar Panel (FM123) 10 watt (FM121) 5 watt -requirestwo-5wattpanels

The Solar Panel is a 10 watt solar powered battery charger for use with the FM350 & FM352 gate
operator systems. Particularly suited for remote installations, each Solar Panel comes with tubular
steel support, mounting clips, wire connectors, and 8 ft. of low voltage wire (see Low Voltage Wire
for additional wire). The Mighty Mule® 352 control board has clearly labeled terminal connections
for easy installation of the Solar Panel. Installation in some regions of the world will require multiple
solar panels for adequate charging power. Dual gates require a minimum of 10 watts of solar
charging power. (5 watt panels require 2 panels)

Push Button Control (FM132)

Unlit doorbell button for remote entry or exit control. Wires directly to the control board and uses 16
gauge multi-stranded, dual conductor low voltage wire (sold separately).

Pin Lock (FM133)

The Pin Lock substitutes for the clevis pin at the front end of the Mighty Mule® 352 gate openers.
Helps prevent theft of the operator from the gate, while allowing quick release of the operator.

Key Chain Two Button Transmitter (FM134)

The Key Chain Transmitter is a dual button version of the Mighty Mule® single button entry
transmitter and has the same adjustable code settings. Used for 2 gates or 1 gate and garage door.
(battery is included)

Single Button Transmitter (FM135)

The Mighty Mule® entry transmitter, with adjustable code settings, is standard equipment with all
Mighty Mule® 352 systems. (battery is included)

Digital Keypad (FM137)

The specially designed digital keypad can be easily installed as a wireless or wired keypad. It can
be programmed to use up to 25 different personal identification number (PIN) codes. Each code is
face programmable with additional security features built in. Wired installations require 16 gauge,
low voltage, multi-stranded, dual conductor, direct burial wire (sold separately). Requires 3 AA
batteries (not included).

Mounting Post (FM100) - In Ground

This black powder coated pedestal is designed to provide convenient access to your keypad,
wireless intercom, or other access control device from your vehicle. With its break down design it
is easy to install and works well in most standard applications. Surface Mount Flanges (F102) and
Extensions (F103) for added height are available.

Mighty Mule® Vehicle Sensor (FM138)

The Gate Opening Sensor is designed for residential and agricultural applications and is compatible
with most Mighty Mule® automatic gate opener models (see Sensor Box for model compatibility).

The Sensor is an electromagnetic sensor, which offers 'hands free' operation of the Mighty Mule®

Gate Operator with a 12 ft. radius of detection of vehicles in motion.

A wireless version of the Gate Opening Sensor is available. (FM130)

Mighty Mule 352

43

Accessories are Available From Your Retail Store (con't)

AUTOMATIC
GATE LOC K

Automatic Gate Lock Pull-to-Open (FM143)

A MUST for added security. Solenoid driven, with a steel housing. Unlocks and locks automatically
as gates open and close. Used with Mighty Mule® DC swing gate operating systems for maximum
stability and security. Comes with a keyed manual release. Recommended for gates over 8 ft. long.
Ideal for animal enclosures or high wind areas.

Wireless Entry Intercom / Keypad (FM136)

Allows owner to screen guest at the gate before allowing access to the property. Keypad also allows
owner to give up to 25 programmable entry codes to family, friends or approved delivery personnel.
Codes can be permanent of temporary. Can be wireless up to 500 feet or hard wired up to 1000 feet.
Additional base stations available (F3101MBC).

Low Voltage Wire (RB509)

The 16 gauge, multi-stranded, dual conductor Low Voltage Wire is for connecting the AC powered
transformer, or the Solar Panel to the control board. Also used for the connection of accessories,
such as locks, keypads, push buttons and other wired control devices. This specially designed wire

is UV treated, PVC coated and ready for direct burial. Available in 1000' rolls or special lengths.

Driveway Alarm (FM131)

Keep track of the comings and goings on your property with this electromagnetic sensor alert
system. When a vehicle passes the sensor, the receiver emits an audible tone and lets you know
someone’s there. Functional range of up to 400 ft. Easy-to-install and stake is included in kit.
Transmitter requires 2 “C” batteries (not included)

Wireless Driveway Vehicle Sensor (FM130)

The wireless gate opening sensor offers hands free operation of the Mighty Mule Gate Opener. Works
wirelessly up to 100 feet from the gate. Transmitter, receiver and two AA batteries are included.

Push to Open Bracket (FM148)

Required when Mighty Mule® 350/352 gate operator(s) must push the gate open, such as on a sloping
driveway or where space prevents gate(s) from opening inward (pulled open). Order two PTO brackets for

conversion of a dual swing gate installation.

Column Mount Lock Receiver (433IH)

For mounting the Automatic Gate Lock on brick columns, walls, or for other applications with limited
space between gate and post.

Replacement Transformer (RB570)

Standard 18 volt, 2200 mA, AC transformer for maintaining the battery included with the Mighty Mule®
352 gate operator. This is the only transformer approved for use with all UL325 Mighty Mule® gate

operator systems.

Universal Receiver (RB709U-NB)

The Universal Receiver allows you to use the same Mighty Mule® 352 entry transmitter to operate your
gate operator and your garage door operator. Compatible with most garage door operators.

If you have a question about any special order item,

just call 1-800-543-GATE!

The contents of all material available on this installation manual are copyrighted by GTO, Inc. (“GTO”), unless otherwise indicated. All rights are reserved by GTO, and content may not be
reproduced, downloaded, disseminated, published, or transferred in any form or by any means, except with the prior, written permission of GTO. Any reprinting of GTO publications is by

Mighty Mule¨, E-Z Gate¨, GTO¨, are registered trademarks of GTO, Inc. America’s DIY Automatic Gate Openers is a trademark of GTO, Inc. and are the exclusive property of GTO, Inc.

All rights are reserved by GTO, and these marks may not be used, in any for without the prior, written permission of GTO.

permission only. Copyright infringement is a violation of federal law.

(“GTO”).