Cattron LOFA MC704 Operating instructions

LOFATM MC704
Panel Operation and Troubleshooting Manual
9M02-3000-A001-EN

LOFATM MC704
Panel Operation and Troubleshooting Manual
2
9M02-3000-A001-EN
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Revision History
VERSION
DATE
NOTES
2006
Initial Release
A
05/2006
Corrected typographical errors
B
10/2006
Added symbols to Indicators, corrected typographical errors
C
01/2007
Updated schematics, removed Power Box information
C.1
02/2007
Added part numbers
D
06/2014
Updated format, added schematics, removed Power Box information
A
05/2015
B
10/2016
D
12/2020
Document rebranded and contact information updated
Any information furnished by Cattron™ and its agents is believed to be accurate and reliable. All specifications are subject to change without notice.
Responsibility for the use and application of Cattron products rests with the end user since Cattron and its agents cannot be aware of all potential uses.
Cattron makes no warranties as to non-infringement nor as to the fitness, merchantability, or sustainability of any Cattron products for any specific
or general uses. Cattron Holdings, Inc., or any of its affiliates or agents shall not be liable for incidental or consequential damages of any kind. All
Cattron products are sold pursuant to the Terms and Conditions of Sale, a copy of which will be furnished upon request. When used as a tradename
herein,
Cattron means Cattron Holdings, Inc. or one or more subsidiaries of Cattron Holdings, Inc. Cattron™, corresponding logos, and other marks
are
trademarks or registered trademarks of Cattron Holdings, Inc. Other marks may be the property of third parties. Nothing herein provides a license under
any Cattron or any third party intellectual property right.

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Contents
1 Introduction...........................................................................................................................................................5
2 Important Safety Information................................................................................................................................6
3 Operation..............................................................................................................................................................7
3.1 Preheat Options........................................................................................................................................8
3.1.1 Preheat Output ............................................................................................................................8
3.2 Indicators ..................................................................................................................................................8
3.2.1 Battery LED (Red) .............................................................................................................8
3.2.2 Oil Pressure LED (Red) ................................................................................................8
3.2.3 Temperature LED (Red) ........................................................................................................9
3.2.4 AUX LED (Red) ................................................................................................................9
3.2.5 Preheat/OK LED (Green) ....................................................................................................9
3.3 Harness.................................................................................................................................................. 10
3.3.1 Sealed Connectors ................................................................................................................... 10
3.3.2 Unsealed Connectors ............................................................................................................... 10
3.3.3 Harness Routing ....................................................................................................................... 10
3.4 Battery Circuit Requirements................................................................................................................. 11
3.4.1 Battery Positive Connection ..................................................................................................... 11
3.4.2 Battery Negative Connection (Grounding) ............................................................................... 11
3.4.3 Voltage Drop............................................................................................................................. 12
3.5 Suppression of Voltage Transients (Spikes) ......................................................................................... 12
3.6 Welding on Equipment with Electronic Controls.................................................................................... 13
4 Troubleshooting ................................................................................................................................................ 14
4.1 General Troubleshooting ....................................................................................................................... 14
4.2 Fuel Run/Stop Solenoid Troubleshooting.............................................................................................. 15
4.3 Preheat Troubleshooting ....................................................................................................................... 16
4.4 Panel Troubleshooting........................................................................................................................... 16
4.4.1 Testing Shutdown Inputs .......................................................................................................... 17
5 Typical Schematics ........................................................................................................................................... 18
6 Additional Information ....................................................................................................................................... 20
6.1 Products/Deliverables............................................................................................................................ 20

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7 Technical Support ............................................................................................................................................. 21

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1 Introduction
This document provides general information on LOFA™ MC704 panel operation and troubleshooting. MC704
panels are a flexible platform for diesel engine control, monitoring and protection, featuring LOFA™’s powerful
First Fault Diagnostics (FFD). After pinpointing the initial failure, FFD stores it in memory and alerts the end
user via a single bright LED. FFD monitors battery charge, low oil pressure, high temperature and one additional
contact closure input. The microprocessor-based solid-state design uses high-power semiconductors instead of
outdated electromechanical relays to ensure reliable high-current switching.
The MC704 panels are offered in two versions. The MC704HP has a built-in tamperproof LED hourmeter while
the reduced cost MC704LCP eliminates the hourmeter. Both versions can be factory configured with specific
preheat and afterglow requirements. If preheat is not required, this output can function as an alarm.
All standard panels feature a 12-inch wiring harness terminating into a sealed weather-proof plug. This
robust universal wiring connection performs well in harsh environments and allows interchanging a number
of different panels and harnesses. This design allows for simplified installation as well as a flexible means to
incorporate custom plug-and-play engine wiring harnesses and standard harness extensions.
Note: The engine harness is not included with the panel.
A number of standard engine harnesses are available, or Cattron can develop a custom harness for
your exact needs.
Generic harnesses in various lengths are available for field customization.
WARNING
WHEN REPLACEMENT PARTS ARE REQUIRED, CATTRON RECOMMENDS USING
REPLACEMENT PARTS SUPPLIED BY CATTRON OR PARTS WITH EQUIVALENT
SPECIFICATIONS.
FAILURE TO HEED THIS WARNING CAN LEAD TO PREMATURE FAILURE, PRODUCT DAMAGE,
PERSONAL INJURY OR DEATH.
!

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2 Important Safety Information
Please note the following important safety information:
•The warnings in this publication are not all inclusive
•Cattron cannot anticipate every potential hazard
•Appropriate safety rules and precautions should be followed with any tool, work method or operating
procedure
•Improper procedures, tools and materials may cause damage or make the equipment unsafe to operate
•Only persons with appropriate training, skills and tools should perform these functions
•Improper operation, maintenance or repair of this product can be dangerous and may result in injury or
death
•Do not operate or perform any maintenance or repair on this product until all operation, maintenance and
repair information is read and understood
•The information, specifications and illustrations in this publication are based on information available at
the time of publication
•All items are subject to change at any time without notice

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3 Operation
Turning the panel key to the run position starts a self-test which causes all LEDs to flash three times, activates the
alarm output (if preheat is not used) for one second and enables the fuel run/stop solenoid output. After self-test,
the LEDs indicate the state of the inputs they monitor. The normal indications are battery charge and oil pressure
on most applications. If these LEDs are not illuminated at this time, it may indicate the inputs are not properly
connected.
The Preheat/OK LED begins to blink when the key switch is turned to the run position if automatic preheat is
configured (see the Preheat Options section). Preheat time varies from application to application. After waiting for
the Preheat/OK LED to become solid, the engine is cranked by turning and holding the key switch in the start
position until the engine starts. The key switch is spring loaded to return automatically to the run position when
released.
Note: The key switch is equipped with a mechanical start locking device.
An attempt to crank the engine again can only be made by turning the key switch to the off position to
reset the start locking mechanism.
If the engine is not started within 30 seconds of turning on the panel, the fuel run/stop solenoid output is turned off
to prevent battery discharge when the key switch is left in the run position. The fuel run/stop solenoid output is
turned off after 30 seconds even if preheating. As soon as the key switch is turned to the start position, the
solenoid output is enabled. The afterglow cycle begins when the key switch returns to the run position.
Note: If conditions do not warrant preheat, the engine may be started by turning the key to the start position
without waiting for the preheat time to expire.
Panel instrument power, including the hourmeter and voltmeter, is provided by the fuel run/stop solenoid output. If
the instruments do not power up when the key is turned to the run position, this indicates a problem with the
solenoid circuit (see the Fuel Run/Stop Solenoid Troubleshooting section).
After the engine starts, the panel electronics ignore all shutdown conditions for the first 10 seconds. This delay
eliminates the requirement to hold a by-pass override button during starting and allows the engine conditions such
as oil pressure to normalize. The 10-second timer starts when the key switch returns to the run position.
Note: Starter input is required for correct panel operation. If the starter motor input is not activated (connected
to battery positive) and the engine is started through another means (i.e., air starter) the engine will
shutdown 30 seconds after the key switch is turned to the run position.
To prevent unintentional engine shutdowns caused by intermittent conditions (for example, pressure spikes or
coolant movement), the panel requires a constant 1/3-second fault input to cause engine shutdown.
WARNING
WHEN USED IN COMBINATION WITH MECHANICAL FLOAT TYPE SWITCHES, ENGINE
VIBRATIONS MAY PREVENT CONSTANT CONTACT CLOSURE.
!

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3.1 Preheat Options
3.1.1 Preheat Output
Preheat is a 3 A positive output for control of an external power relay with predetermined preheat and afterglow
times. A relay should be selected with appropriate amperage capacity for the installed cold starting aid
(glowplug, intake air heater, etc.). Applications using multiple cold starting aids may require multiple relays.
Note: Consult engine documentation when selecting cold starting aid, power relay and heating specifications.
3.2 Indicators
3.2.1 Battery LED (Red)
A solidly illuminated Battery LED indicates a battery charge failure. A battery charge failure may be caused by
a faulty alternator, broken drive belt or the alternator not excited. A battery voltage reading of approximately
14 V on 12 V systems (28 V on 24 V systems) while the engine is running indicates the battery is charging
properly. Irregular blinking of the Battery LED may indicate a failing charge circuit. The panel can be factory
configured to indicate only battery charge failure.
3.2.2 Oil Pressure LED (Red)
A solidly illuminated Oil Pressure LED indicates low oil pressure failure. The panel typically senses low oil
pressure from a ground contact switch on the engine. When a sender/switch combination is used on the engine,
the marking WK generally indicates the switch terminal. This input typically expects a normally closed switch
(ground contact when oil pressure is low). A defective switch or shorting the shutdown input to ground can cause
low pressure fault indication. Additionally, when using sender/ switch combinations, swapping the WK and G
terminal can cause unintended shutdowns. The panel can be factory configured to indicate only oil pressure
failure.
WARNING
LOW OIL PRESSURE IS NOT AN INDICATION OF LOW OIL LEVEL.
FOR THE BEST POSSIBLE PROTECTION, CATTRON RECOMMENDS USING OUR SOLID-STATE
OIL LEVEL SHUTDOWN SWITCH.
Note: Most shutdown switches are grounded through the switch body.
Do not use insulating sealant (i.e., Teflon tape) when installing switches.
!

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3.2.3 Temperature LED (Red)
A solidly illuminated Temperature LED indicates high engine temperature failure. The panel typically senses high
temperature from a ground contact switch on the engine. When a sender/switch combination is used on the
engine, the marking WK or Wgenerally indicates the switch terminal. This input typically expects a normally open
switch (ground contact when engine temperature is too high). A defective switch or shorting the shutdown input to
ground can cause an over temperature fault indication. Additionally, when using sender/switch combinations,
swapping the WK or Wand Gterminal can cause unintended shutdowns. The panel can be factory configured to
indicate only temperature failure.
WARNING
IF THE TEMPERATURE SWITCH IS NOT IN
CONTACT WITH COOLANT DUE TO COOLANT LOSS,
THE ENGINE IS NOT PROTECTED FROM OVERHEATING.
FOR THE BEST POSSIBLE PROTECTION, CATTRON RECOMMENDS USING OUR SOLID-STATE
COOLANT LEVEL SHUTDOWN SWITCH.
Note: Most shutdown switches are grounded through the switch body.
Do not use insulating sealant (i.e., Teflon tape) when installing switches.
Some thermostat housings are composites and do not provide ground for the switch.
3.2.4 AUX LED (Red)
A solidly illuminated AUX LED indicates auxiliary failure (i.e., coolant level, oil level, belt breakage, hydraulic
pressure, etc.). The panel typically senses failure using a ground contact switch. Auxiliary inputs are equipment
specific and determined by the equipment manufacturer. A defective switch or shorting the shutdown input to
ground can cause fault indications. The panel can be factory configured to indicate only AUX failure.
3.2.5 Preheat/OK LED (Green)
A blinking green Preheat/OK LED is the panel preheat indication. When the LED changes to solid, the preheat
period is complete and the engine may be cranked. The LED changes to solid illumination when the engine starts.
There is no indication of afterglow.
!

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3.3 Harness
3.3.1 Sealed Connectors
The provided sealed weather-proof plug includes a grey locking device which must be released to separate the
connectors. Press the tab on the connector housing to release the connectors.
WARNING
CATTRON DOES NOT RECOMMEND USING DIELECTRIC GREASE OR SEALANT WITH SEALED
CONNECTORS. THESE CHEMICALS MAY CAUSE SEAL DAMAGE AND ALLOW WATER ENTRY.
USE CATTRON PROVIDED CAVITY PLUGS TO SEAL THE CONNECTOR IF WIRES ARE
REMOVED.
3.3.2 Unsealed Connectors
For unsealed connectors exposed to the elements, Cattron recommends using dielectric grease to protect
contacts.
WARNING
CATTRON DOES NOT RECOMMEND USING SEALANT WITH UNSEALED CONNECTORS.
SEALANT TRAPS MOISTURE IN THE CONNECTOR AND ENCOURAGES CORROSION.
3.3.3 Harness Routing
The minimum routing radius of the wiring harnesses should be at least two times the diameter of the wiring
harness. Bends should be avoided within 1 inch (25 mm) of any connector in order to avoid seal distortion and
potentially allowing moisture to enter the connector.
Note: For a harness length in excess of 10 ft, a relay must be added to the start solenoid circuit.
A relay may also be required for the fuel run/stop solenoid.
Cattron offers starter relay kits for mounting near the engine.
!
!

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3.4 Battery Circuit Requirements
3.4.1 Battery Positive Connection
The electronic panel operates on either 12 VDC or 24 VDC electrical systems. The unswitched battery positive
connection to the panel is made at the weather-proof connector. The panel provides switched positive battery.
Protection for the unswitched battery positive circuit is dependent on specific equipment configuration. The
overload protection should not exceed 125% of the sum of all output currents plus 5 A for the panel. Powering the
panel through dedicated circuits with appropriate overload protection reduces the possibility of panel damage.
Circuit breakers are preferred over in-line fuses for circuit protection. Overcurrent protection devices should
ideally be located in a central location. If automatic reset circuit breakers are used, consideration of the
environment of the breaker is critical and may affect the trip point. The trip point of some circuit breakers can be
significantly reduced below the rated trip point if the circuit breaker is exposed to high temperatures.
WARNING
DISCONNECTING THE BATTERY WHILE THE ENGINE IS RUNNING MAY DAMAGE ELECTRICAL
COMPONENTS.
WHEN USING A BATTERY DISCONNECT SWITCH, CATTRON RECOMMENDS USING A 2-POLE
SWITCH TO DISCONNECT BOTH THE BATTERY AND ALTERNATOR OUTPUT.
3.4.2 Battery Negative Connection (Grounding)
WARNING
IMPROPER GROUNDING CAN CAUSE ELECTRICAL NOISE OR UNRELIABLE OPERATION AND
MAY DAMAGE THE PANEL OR OTHER COMPONENTS. ALL GROUND CONNECTIONS MUST BE
FREE FROM FOREIGN MATERIALS, INCLUDING PAINT, WHICH MAY INTERFERE WITH PROPER
GROUNDING.
A RELIABLE GROUND MUST BE PROVIDED FOR THE PANEL. CATTRON RECOMMENDS
THE GROUND CONNECTION BE MADE DIRECTLY TO THE BATTERY NEGATIVE.
GROUNDING THROUGH FRAME MEMBERS IS NOT RECOMMENDED.
ALL GROUND PATHS MUST BE CAPABLE OF CARRYING ANY LIKELY FAULT CURRENTS.
DO NOT REVERSE THE BATTERY POLARITY. ATTEMPTING TO CRANK THE ENGINE WHEN
THE POLARITY OF THE BATTERY CONNECTIONS IS REVERSED MAY DAMAGE THE PANEL.
Note: A maximum of three ring terminals should be connected to a ground stud to ensure integrity of the
ground connection. The use of more than three terminals can cause the connection to become loose.
!
!

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3.4.3 Voltage Drop
If panel voltage drops below 6 V for more than 0.1 seconds, the panel may reset, causing the self-test to
reactivate and the engine to shut down after 30 seconds. Resetting the panel is equivalent to quickly turning the
key switch to off and back to run without starting the engine. Since the panel did not sense a start signal, the fuel
run/stop solenoid deactivates after 30 seconds. Voltage drops can be caused by external equipment inrush
current, improper wire sizes or faulty wiring. Relays may be needed for long wire runs.
3.5 Suppression of Voltage Transients (Spikes)
WARNING
THE INSTALLATION OF VOLTAGE TRANSIENT SUPPRESSION AT THE TRANSIENT SOURCE IS
REQUIRED.
CATTRON FOLLOWS SAE RECOMMENDED ELECTRICAL ENVIRONMENT PRACTICES.
Inductive devices such as relays, solenoids and motors generate voltage transients and noise in electrical circuits.
Unsuppressed voltage transients can exceed SAE specifications and damage electronic controls.
Relays and solenoids with built-in voltage transient suppression diodes are recommended whenever possible.
Refer to the illustration below for proper installation of diodes when built-in voltage transient suppression is not
available.
Locate inductive devices as far as possible from the components of the electronic panel. When using electric
motors, it may also be necessary to add isolation relays to eliminate voltage transients and noise and to prevent back
feed.
Note: Cattron harness assemblies typically include all required engine control suppression devices.
Added equipment will require additional protection.
!

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3.6 Welding on Equipment with Electronic Controls
Proper welding procedures are required to avoid damage to electronic controls, sensors and associated
components. The component should be removed for welding if possible.
The following procedure must be followed if the component must be welded while installed on equipment with
electronic controls. This procedure will minimize the risk of component damage.
WARNING
DO NOT GROUND THE WELDER TO ELECTRICAL COMPONENTS SUCH AS THE CONTROL
GROUND OR SENSORS. IMPROPER GROUNDING CAN CAUSE DAMAGE TO ELECTRICAL
COMPONENTS.
CLAMP THE GROUND CABLE FROM THE WELDER TO THE COMPONENT BEING WELDED.
PLACE THE CLAMP AS CLOSE AS POSSIBLE TO THE WELD TO REDUCE THE POSSIBILITY OF
DAMAGE.
1. Stop the engine. Turn the key switch to the OFF position.
2. Disconnect the negative battery cable from the battery.
3. Open any installed battery disconnect switch.
4. Unplug the panel if possible.
5. Connect the welding ground cable as close as possible to the area to be welded.
6. Protect the wiring harness from welding debris and spatter.
7. Use standard welding methods to weld the materials.
!

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4 Troubleshooting
4.1 General Troubleshooting
For additional information, refer to the engine manufacturer troubleshooting guide.
No response from starter motor
Possible Cause
Possible Remedy
No battery voltage to starter Verify wiring and battery connection (power and ground)
Battery discharged Charge or replace battery; verify alternator charging
Tripped overcurrent protection Correct fault; replace or reset overcurrent protection
No signal from panel No power to panel (see Panel Troubleshooting section)
Defective starter solenoid Replace starter solenoid
Defective starter motor Replace starter motor
Engine will crank but not start
Possible Cause
Possible Remedy
Engine not getting fuel Check fuel level, filter, fuel pump; verify no air in fuel lines
Fuel run/stop solenoid not engaged See Fuel Run/Stop Solenoid Troubleshooting section
Tripped overcurrent protection Correct fault, replace or reset overcurrent protection
No preheat (cold condition) See Preheat Troubleshooting section
Engine runs for 10 seconds and shuts down
Possible Cause
Possible Remedy
Shutdown switch input active Verify shutdown source exists; correct condition or correct faulty
circuit
Battery not charging Verify alternator charging (see Alternator not charging battery table)
Control board did not sense start
signal
Engine started through alternate method (i.e., manual air start, push
start, etc.)
Defective panel See Panel Troubleshooting section
Engine runs longer than 10 seconds and shuts down
Possible Cause
Possible Remedy
Shutdown switch input active Correct engine fault; verify shutdown switch wiring
Circuit overload protection tripped Correct overload; keep panel from overheating (over 185°F/85°C)
Voltage transients (spikes)
Add suppressor diodes; protect from nearby lightning strikes; shield
induced spikes from other equipment; add electric motor control
relay push start, etc.
Defective panel See Panel Troubleshooting section

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Alternator not charging battery
Possible Cause
Possible Remedy
Broken or slipping alternator drive belt Adjust or replace alternator drive belt
Alternator not excited Verify excitation circuit connected; replace faulty regulator; add
additional excitation resistor
Alternator output not connected Install charge wire
Alternator not grounded Clean or add ground connection
Alternator faulty Replace faulty alternator
4.2 Fuel Run/Stop Solenoid Troubleshooting
Engine does not stop immediately
Possible Cause Possible Remedy
Back feed from motor (i.e., cooling fan) Add relay or blocking diode
Sticking solenoid linkage Repair or replace solenoid linkage
Fuel valve without check valve Install or repair check valve
Fuel run/stop solenoid does not engage
Possible Cause
Possible Remedy
No power to solenoid Locate reason for lack of power and correct (Circuit overloaded?
Failed suppressor diode? Faulty wiring?)
No power to solenoid pull coil Correct faulty wiring; check pull control circuit
Incorrect linkage adjustment Adjust solenoid linkage
Faulty solenoid Replace solenoid
Failed suppressor diode Correct wiring (diode reversed?); replace suppressor diode
Optional e-stop engaged Disengage e-stop
Engine not getting fuel
Possible Cause Possible Remedy
Empty fuel tank Fuel engine
Clogged filter Replace filter
Air in fuel lines Bleed fuel lines
Low fuel pressure Replace faulty fuel pump and/or clogged filter
Faulty fuel pump Replace fuel pump; correct wiring fault (electric fuel pump)

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4.3 Preheat Troubleshooting
Engine is hard to start in cold conditions
Possible Cause
Possible Remedy
Start attempt before preheat complete Wait for preheat time to elapse, and crank as soon as time elapses
Incorrect preheat specification Correct panel configuration; install correct panel
Heater faulty Replace heater
Heater relay faulty Replace relay
Preheat control not functioning Correct wiring; correct panel configuration
Faulty panel See Panel Troubleshooting section
Engine produces excessive white smoke after starting
Possible Cause
Possible Remedy
Afterglow not enabled Reconfigure panel
Heater faulty Replace heater
Heater relay faulty Replace relay
Preheat control not functioning Correct wiring; correct panel configuration
Faulty panel See Panel Troubleshooting section
4.4 Panel Troubleshooting
Panel does not perform self-test
Possible Cause
Possible Remedy
Tripped overcurrent protection Correct fault; replace or reset overcurrent protection
Faulty connection to battery Correct battery connections (see Battery Circuit Requirements
section)
Panel performs normal self-test, engine cranks, runs and shuts down
Possible Cause Possible Remedy
Only Battery LED Illuminated Correct battery charge failure (see Battery not charging item)
Only Oil Pressure LED Illuminated Correct low oil pressure condition or faulty switch; correct wiring fault
Only Temperature LED Illuminated Correct overheating condition or faulty switch; correct wiring fault
Only Aux LED Illuminated Correct fault condition (i.e., v-belt, coolant level) or faulty switch;
correct wiring fault
All normally closed shutdowns
illuminate for one second (panel reset)
Add suppressor diodes; protect from nearby lightning strikes; shield
induced spikes from other equipment; add electric motor control
relay

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4.4.1 Testing Shutdown Inputs
Shutdown switches signal a fault by ground contact in most systems. Shutdown operation can be verified by
grounding the shutdown inputs individually. It may be necessary to remove the wire from the shutdown switch to
perform this test.
Note: Most shutdown switches are grounded through the switch body.
Do not use insulating sealant (i.e., Teflon tape) when installing switches.
Some thermostat housings are composites and do not provide ground for the switch.

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5 Typical Schematics
The following figures show typical schematics. The details will vary from installation to installation. Please see the
specific schematics for the particular installation for details.

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6 Additional Information
6.1 Products/Deliverables
Licensed Product Information
•Software codes with product numeric values equal to 001-xxxx-yyyy-zzz; where xxxx, yyyy, and zzz equal
(0000...9999)
•Software codes qualified under the same numeric regimen detailed above or including the verbal
description of “CANPlus™” products and/or the “CANPlus Suite” of products