Installation and Operation of the Exhaust Monitor Used in All Diesel Particulate Filter (DPF) Retrofit Emissions Applications{1091, 1408, 7490, 7498} Caterpillar

Caterpillar Products: All

Introduction

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NOTICE
Diesel Particulate Filters (DPF) are not applicable to all engines. A Diesel Particulate Filter should typically not be applied to engines that are not regulated. Diesel Particulate Filters are meant for usage on only diesel engines. This technology does not apply to gas engines. Consult with Caterpillar in order to determine if a Diesel Particulate Filter can be used on your engine.

The exhaust monitor is a device designed to continuously monitor the Caterpillar Diesel Particulate Filter (DPF) system. The exhaust monitor provides critical information to the vehicle operator and maintenance personnel relative to operation and performance of the Diesel Particulate Filter.

Information that is included in this special instruction is a description of the exhaust monitor group, general guidelines for proper installation of the exhaust monitor, and operation instructions.

Please read each section carefully before you install your exhaust monitor and before you operate your exhaust monitor.

This special instruction has general information and instructions. if you have questions regarding your specific installation, please contact Caterpillar.

Note: Federal and CARB verification requires that every vehicle equipped with a Diesel Particulate Filter must install and operate a back pressure monitoring device such as the exhaust monitor. Contact Caterpillar if you have questions regarding your specific requirements.

Caterpillar Exhaust Monitor

Warranty and Record of Installation

Caterpillar dealers will record the installation of the exhaust monitor as part of the warranty validation for the DPF system.

Be sure to record the information from the exhaust monitor (serial number) in order to validate the product warranty.

Parts Information

271-6537 Exhaust Monitor Group

The package that contains the exhaust monitor group includes the following:

Illustration 1	g01427073
Exhaust Monitor Group Parts List (1) Weather pack silicon seal (2) Weather pack plug connector (3) 302-1563 Exhaust Monitor Group (Weather resistant) (4) 271-6538 Connector (5) Weather pack receptacle connector (6) Weather pack socket terminal (7) Weather pack pin terminal

• Four Weather pack silicon seals (1)

• One Weather pack plug connector (2)

• One 302-1563 Exhaust Monitor Group (Weather resistant) (3)

• One 271-6538 Connector (4)

• One Weather pack receptacle connector (5)

• Weather pack socket terminal (6)

• Weather pack pin terminal (7)

• One 216-7994 Thermocouple

• Four Self-tapping screws with washers

• One User's Manual

216-7990 Installation Assembly

The installation assembly includes the following:

Illustration 2	g01590964
(1) Tee fitting (2) Tube connector (3) Reducer fitting

• One Tee fitting (1)

• One Tube connector (2)

• One Reducer fitting (3)

• 6.1 m (20 ft) of Extension Tube (1/4 inch OD, thick wall copper)

• 9.1 m (30 ft) of White-14 AWG Wire

• 9.1 m (30 ft) of Red-14 AWG Wire

• 6.1 m (20 ft) of Green-18 AWG Wire

• 6.1 m (20 ft) of Blue-18 AWG Wire

• Four Terminals (for ECM interface)

• One 3 amp ATO Fuse (blade type fuse)

• One Fuse Holder for a ATO style fuse

• 6.1 m (20 ft) length of Wire Loom

220-3778 Adapter Cable Assembly

The adapter cable assembly includes the following:

• One adapter cable assembly

282-0031 Remote Display

The remote display includes the following:

Illustration 3	g01614718

• One Remote LED display (1)

• One "Y" power adapter (2)

System Description

The exhaust monitor monitors exhaust temperature and back pressure of the DPF system. The exhaust monitor will warn the operator of the need for cleaning the filter or of a potential problem with the exhaust system that may exist. The exhaust monitor is equipped with internal memory, recording the temperature, back pressure, and alarm events that occur during vehicle operation. Data is accumulated by the exhaust monitor over time and this accumulated data can be downloaded directly to a PC via a serial data link for further analysis. The exhaust monitor contains alarm outputs which activate the LED lights on a remote LED display.

Exhaust Monitor

The package for the exhaust monitor is durable and the exhaust monitor is capable of withstanding a wide temperature range. The exhaust monitor is designed to be retrofitted into off-highway machines.

Exhaust temperature is monitored with a thermocouple probe that is installed in the inlet section of the Diesel Particulate Filter. Exhaust back pressure is measured with a pressure transducer that is located within the exhaust monitor and connected to the Diesel Particulate Filter inlet section with an extension tube. Data for temperature and pressure is collected on a continuous basis and monitored in order to detect conditions that exceed defined limits.

Refer to Illustration 4 for the location of the external components on the exhaust monitor. A brief description follows for each component.

Illustration 4	g01590913
Exhaust Monitor (1) Serial Data Communication Port (2) System Status LED (3) Over Pressure Alarm LED (4) Over Temperature Alarm LED (5) System Problem LED (6) Alarm Reset Button (7) Pressure Transducer Port (8) Thermocouple Connector (Outlet) (9) Power Connector (10) Thermocouple Connector (Inlet) (11) Alarm Output Connector (12) Mounting Hole (13) Mounting Nut

1. Serial Data Communication Port (1). A communication data link to a PC or to a laptop computer is established through this connector. See the topic "Communications Software" in this special instruction for more information.

2. System Status LED (2). A flashing green LED indicates system status.

3. Over Pressure Alarm LED (3). A red LED illuminates when the preset limit for a "High Backpressure Alarm" has been reached.

4. Over Temperature Alarm LED (4). A red LED illuminates when the preset limit for a "High Temperature Alarm" has been reached.

5. System Problem LED (5). A red LED illuminates whenever the exhaust monitor detects a problem with the pressure transducer or the thermocouple.

6. Alarm Reset Button (6). Pressing the alarm reset button will turn off any lighted LED on the exhaust monitor, provided that an alarm condition no longer exists.

7. Pressure Transducer Port (7). The extension tube from the Diesel Particulate Filter inlet section connects to this port.

8. Thermocouple Connector (Outlet) (8). This connector is used only if the exhaust monitor is being used with two thermocouples. If this connector is not being used, please leave the red cap on the connector.

9. Power Connector (9). Power from a 12 or 24 volt unswitched power supply is supplied to the exhaust monitor through this connector.

10. Thermocouple Connector (Inlet) (10). This connector is always used in all applications.

11. Alarm Output Connector (11). Alarm signal is transmitted through this connector to the remote LED display.

12. Mounting Hole (12). Each of the four mounting holes has a grommet. The mounting holes are used to mount the exhaust monitor in the vehicle with the self-tapping screws and washers that are supplied with the exhaust monitor group.

13. Mounting Nut (13). Mounting nuts are used to secure the exhaust monitor's enclosure to the base.

Backup Battery

The exhaust monitor contains a backup battery that saves critical parameters in the event of a power loss to the exhaust monitor. The exhaust monitor will not operate on this battery if power is lost to the exhaust monitor. The battery saves stored data, alarm settings, dates, and time.

The battery must be replaced after every 5 years. Please contact Caterpillar when the battery needs to be replaced. The procedure requires the use of the CRTdm Communications software and the ability to apply low pressure to the exhaust monitor.

Communications Software

If your shop is equipped with a mobile PC or a laptop computer that is running Windows 95 or newer, you will be able to access the data the exhaust monitor stores in memory.

The software for the exhaust monitor is a user friendly, single screen program, that operates under the Windows 95, 98, 2000, and XP operating systems. Once the software is installed on a PC, the software allows communication between the PC and the exhaust monitor. You can download data, graph the data, and diagnose exhaust monitor alarms. The software is available on a compact disc and the software includes a CRTdm Communications Manual, software CD, and adapter cable that allows communications between the PC and the exhaust monitor.

Updates are also available via the internet at the following website:

http://65.202.131.122:8080/

Here, you will find the latest updates for the CRTdm Communications software and the latest firmware. Please contact Caterpillar for a user ID and a password.

This is a valuable tool that will aid in the diagnosis of alarm events from the exhaust monitor. With this software, you will be able to determine the time and the date of an alarm, the back pressure and temperature at the time of the alarm, and the reason for the alarm.

For complete details, consult Caterpillar.

Exhaust Monitor Installation Procedure

The installation of the exhaust monitor should be performed in two stages, mechanical and electrical. Both stages of the installation are included in this special instruction.

Note: When you are installing the exhaust monitor, the following conditions must be met or the warranty may be voided:

• The exhaust monitor must be mounted in a space that has an ambient temperature less than 85 °C (185 °F) during normal vehicle operation. The exhaust monitor must be located away from direct sources of heat such as the engine, exhaust manifolds and radiator.

• The exhaust monitor must be mounted in a location that is not directly exposed to high pressure steam cleaning, solvents, battery fumes, or electrical discharge.

• The exhaust monitor must be connected to 12 or 24 VDC of unswitched power.

• The exhaust monitor must not be exposed to a voltage supply or power surges that are greater than 30 VDC.

• The thermocouple and wire that is supplied with the exhaust monitor must be used with the exhaust monitor. Use of any other thermocouple or wire must be approved by Caterpillar.

Caterpillar recommends mounting the exhaust monitor in a position higher than the DPF inlet. This will reduce clogging of the pressure transducer from water that collects in the extension tube between the DPF system and the pressure transducer.

Note: Caterpillar requires installing the exhaust monitor at the same time as the DPF system to validate the DPF system and exhaust monitor warranties.

Mechanical Installation

Note: Prior to installation of the exhaust monitor, power must be turned off in the vehicle or the batteries must be disconnected.

Preparation

1. Park the vehicle on a level surface and apply the parking brake. Follow all safety precautions that are prescribed by shop policy.

2. Disconnect the batteries or turn off the master battery disconnect switch.

3. Select a location for the exhaust monitor that meets the above criteria. Use the four mounting holes on the exhaust monitor as a template to mark four points, and drill four 9/32 inch holes. Attach the exhaust monitor by using the self-tapping screws and the washers that are supplied in the exhaust monitor group.

   Note: You may need to fabricate additional parts in order to install the exhaust monitor and the remote display. This will depend on the existing features in the location that was selected for the exhaust monitor installation and in the cab.

Every DPF has a threaded boss (1/4 inch internal NPT) that will accept the fittings that are identified in the 216-7990 Installation Assembly . Refer to Illustration 5. Before any fittings are installed on the DPF system, the location of the threaded boss must be accessible so that the thermocouple can be easily inserted into the tee fitting. If the threaded boss is not accessible, the DPF inlet head should be rotated until the threaded boss is accessible.

Installation of the Fittings, Extension Tube, and Thermocouple

Note: Use the following instructions if you are using a installation assembly that is supplied by Caterpillar.

Illustration 5	g01590353
Connections at the DPF Inlet Section (1) Tee fitting (2) Threaded boss (3) Extension tube (4) 216-7994 Thermocouple (5) Reducer fitting

1. Apply a thin coat of 4C-5599 Anti-Seize Compound to the threads of tee fitting (1). Install the tee fitting into threaded boss (2) that is located on the DPF inlet section. Refer to Illustration 5.

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Illustration 6	g01590413
(5) Reducer fitting

2. Insert reducer fitting (5) into tee fitting (1) in line with threaded boss (2). Tighten the locknut on the tee fitting finger tight. Use a 9/16 inch wrench to tighten the locknut for one additional turn. Refer to Illustration 6.

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Illustration 7	g01590574
(A) 50.8 mm (2.0 inch)

3. Insert 216-7994 Thermocouple (4) into reducer fitting (5) completely, and then pull back the thermocouple 50.8 mm (2.0 inch) (A). Tighten the locknut on the reducer fitting finger tight. Use a 7/16 inch wrench to tighten the locknut for one additional turn. Refer to Illustration 7.

   Note: If necessary, the thermocouple may be bent once in order to avoid any interference. Do not bend the thermocouple past 90 degrees.

4. Route the thermocouple's wiring to the exhaust monitor.

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Illustration 8	g01590635

5. Insert one end of extension tube (3) into tee fitting (1) that is at a 90 degree angle to the threaded boss. Tighten the fitting on the tee finger tight. Use a 9/16 inch wrench to tighten the fitting for one additional turn. Refer to Illustration 8.

6. Route the extension tube from the DPF system to the exhaust monitor. Coil the extension tube at least one full loop. All 6.1 ± 0.5 m (20 ± 1.5 ft) of the extension tube must be used. If the distance between the DPF system and the exhaust monitor is less than 6.1 m (20 ft), the excess extension tube should be coiled in loops and mounted in the vehicle.

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Illustration 9	g01590055
(6) Tube connector (7) Pressure Transducer port (8) Exhaust monitor

7. Use a 3/4 inch wrench to install tube connector (6) to pressure transducer port (7) on exhaust monitor (8). Insert the end of extension tube (3) into the fitting on tube connector (6). Tighten the locknut on the fitting finger tight. Use a 9/16 inch wrench to tighten the locknut for one full turn plus an additional 90 degrees. Refer to Illustration 9.

   Note: All 6.1 ± 0.5 m (20 ± 1.5 ft) of extension tube (3) must be used or you may void the warranty on the exhaust monitor.

Electrical Installation

The standard exhaust monitor is a sealed unit with three external pigtails. Refer to Illustrations 4 and 17.

• The power pigtail weather pack connector is connected to the mating connector of the wiring harness from the 12 or 24 VDC unswitched power supply.

• The alarm output and the thermocouple (INLET) are tied together into one pigtail. The alarm output weather pack connector is connected to the mating connector from the remote display. The thermocouple (INLET) weather pack connector is connected to the mating connector of the thermocouple from the DPF inlet section. The thermocouple (INLET) weather pack connector is always used.

• The pigtail with the thermocouple (OUTLET) weather pack connector is a secondary temperature input and is only used when you are using two thermocouples.

Note: When using only one thermocouple, the thermocouple's connector must be connected to the thermocouple (INLET) weather pack connector or else the exhaust monitor will alarm.

The standard installation assembly contains the minimum required wiring for completing the necessary exhaust monitor electrical connections. The following instructions are for the standard installation assembly of the exhaust monitor.

Specialized connectors and wiring harnesses may be available from Caterpillar.

Note: All wiring should be routed in such a way to not allow the wiring to contact heat sources, such as the engine, exhaust manifolds, and radiators. The wires should be protected with the wire loom that is supplied with the 216-7990 Installation Assembly . The wire loom can be secured in the vehicle with wire tie-wraps or other appropriate fasteners.

Unswitched Power Supply Connection

Note: 9.1 m (30 ft) of red-14 AWG wire and white-14 AWG wire are supplied with the 216-7990 Installation Assembly .

1. Locate a 12 or 24 volt power supply that is always available even when the key is turned off.

2. Route the red-14 AWG wire from the positive side of the unswitched power supply to the exhaust monitor. Caterpillar recommends that a 3 amp automotive type fuse be installed between the unswitched power supply and the exhaust monitor.

3. Route the white-14 AWG wire from either the negative side of the unswitched power supply, or any other ground connection, to the exhaust monitor.

4. Insert the wires in the wiring loom in order to protect the wires.

5. Crimp a weather pack pin terminal onto the end of each wire. Refer to the topic "Proper Wiring Connections" in this special instruction for the weather pack crimping procedure.

6. After you have crimped a weather pack pin terminal onto the end of each wire, insert the red-14 AWG wire into the socket location marked "A" on the receptacle connector. Insert the white-14 AWG wire into the socket location marked "B" on the receptacle connector.

7. Plug the weather pack receptacle connector of the wiring harness that you have assembled into the weather pack plug connector of the power pigtail on the exhaust monitor. Refer to Illustration 4.

Proper Wiring Connections

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Illustration 10	g01591275
Typical Example (A) 6.4 mm (0.25 inch) (1) Red-14 AWG wire (Used for power connection) (2) White-14 AWG wire (Used for ground connection) (3) Weather pack silicon seal

1. Slide weather pack silicon seals (3) over the ends of red-14 AWG wire (1) and white-14 AWG wire (2). Strip 6.4 mm (0.25 inch) (A) of insulation from the end of each wire. Slide each silicon seal to the edge of the stripped insulation on the wires. Refer to Illustration 10.

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Illustration 11	g01591522
Typical Example (4) Weather pack pin terminal

2. Using a weather pack crimping tool, crimp one weather pack pin terminal (4) on the bare end of red-14 AWG wire (1) and one on the bare end of white-14 AWG wire (2). Refer to Illustration 11.

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Illustration 12	g01591613
Typical Example (5) Weather pack receptacle connector

3. Insert the pin terminal of red-14 AWG wire (1) into the socket location marked "A" on weather pack receptacle connector (5). Insert the pin terminal of white-14 AWG wire (2) into the socket location marked "B" of weather pack receptacle connector (5). Refer to Illustration 12.

Thermocouple Connection

The 216-7994 Thermocouple is supplied with 6.1 m (20 ft) of wiring attached. A portion of the wire is in a stainless steel shield in order to protect the wire from heat. The rest of the wire is in a brown shield. There is a red wire and a yellow wire inside of the brown shield.

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Illustration 13	g01616379
(A) 12.7 mm (0.5 inch) (B) 6.4 mm (0.25 inch) (1) Thermocouple wire (2) Red wire (3) Yellow wire

1. Strip 12.7 mm (0.5 inch) (A) of brown jacket and foil from thermocouple wire (1), exposing red wire (2) and yellow wire (3). Strip 6.4 mm (0.25 inch) (B) of insulation from the end of each wire. Refer to Illustration 13.

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Illustration 14	g01593403
(5) 271-6538 Connector

2. Open 271-6538 Connector (5) and remove the red seal. Slide the red seal over the thermocouple wire to the edge of the brown jacket. Insert red wire (2) into the "-" or "K" pole and insert yellow wire (3) into the "+" side on the connector. Reassemble the connector. Refer to Illustration 14.

   Note: Make sure that the two wires are not touching inside connector (5). Touching of the wires will cause the thermocouple to short out causing the exhaust monitor to signal an alarm.

3. Plug connector (5) into the thermocouple (INLET) weather pack connector on the exhaust monitor. Connector (5) can only be connected in one way.

   Note: The mating thermocouple connectors can be wired together after being plugged into each other by using mechanics or safety wire. Wire the two halves together by using mechanics or safety wire and trim excess wire.

Remote Display

Illustration 15	g01618153
(1) Remote LED display (2) "Y" power adapter (3) Weather pack receptacle connector (4) Weather pack plug connectors (5) Weather pack receptacle connector (6) Weather pack plug connector

A 282-0031 Remote Display is included with the exhaust monitor group and the remote display will warn a vehicle operator if the exhaust monitor detects an alarm event. The remote display consists of a remote LED display (1) with 4.6 m (15 ft) of wire terminated with two weather pack connectors, and a "Y" power adapter (2) terminated with three weather pack connectors. Refer to Illustration 15.

Note: Failure to install the remote display may void the DPF warranty.

Remote Display Connection

1. Mount remote LED display (1) in a location that is visible to the vehicle operator during operation of the vehicle in the event of an alarm condition.

2. Route the remote LED display's wiring to the exhaust monitor.

3. "Y" power adapter (2), included with the remote display, contains one leg with a weather pack receptacle connector (3) and two legs with weather pack plug connectors (4) .

   1. Plug weather pack receptacle connector (3) of the "Y" power adapter into the weather pack plug connector of the power pigtail on the exhaust monitor.

   2. Plug one of the "Y" power adapter's weather pack plug connectors (4) into the weather pack receptacle connector of the wiring harness that you assembled previously in the "Unswitched Power Supply Connection" procedure in this special instruction.

   3. Plug weather pack receptacle connector (5) of the remote LED display into the "Y" power adapter's other weather pack plug connector (4) .

4. Plug weather pack plug connector (6) on the remote LED display into the receptacle connector of the alarm output on the exhaust monitor.

   Note: Once all of the mechanical connections and electrical connections are complete, reconnect the power to the vehicle. The green LED next to "System Status" should begin flashing on the front of the exhaust monitor indicating that everything is operating correctly. If any of the alarm LED's illuminate immediately after the exhaust monitor is powered up, press the alarm reset button to clear the alarm. If the alarm persists, please contact your Caterpillar dealer.

   Note: The exhaust monitor's power connector MUST BE DISCONNECTED if an electric welder is used on the vehicle. Failure to disconnect the power connector may cause extensive damage to the exhaust monitor and the exhaust monitor warranty may be voided.

Mechanical Installation Diagram

Illustration 16	g01427569
Exhaust Monitor Hardware Installation (1) Thermocouple (1/8 inch diameter Type K ) (2) Reducer fitting (3) Tee fitting (1/4 inch tube x 1/4 NPT) (4) Threaded boss (1/4 NPT boss welded onto DPF inlet section) (5) Apply a thin coat of 4C-5599 Anti-Seize Compound to threads (6) Extension tube (6.1 m (20 ft) of 1/4 in OD thick wall copper) (7) Tube connector

Electrical Installation Diagram

Illustration 17	g01594151
Exhaust Monitor Electrical Connections (1) Exhaust Monitor side (2) Harness side (3) Power Pigtail (4) To unswitched power supply (5) Red-14 AWG wire goes to "A" (6) White-14 AWG wire goes to "B" (7) 12 or 24 VDC unswitched power source (8) Thermocouple (Outlet) (9) To thermocouple (Outlet) (10) Red wire goes to "-" or "K" (11) Thermocouple (Outlet) (Secondary temperature input; Only used when two thermocouples are used) (12) Yellow wire goes to "+" (13) Thermocouple (Inlet) (14) To thermocouple (Inlet) and engine ECU (15) Red wire goes to "-" or "K" (16) Thermocouple (Inlet) (Primary temperature input; Always used) (17) Yellow wire goes to "+" (18) Alarm output (19) To remote LED display (20) Yellow LED (Warning) on remote LED display (21) Red LED (Warning) on remote LED display

Operation

Adjust the program in the exhaust monitor to specified parameters by connecting through the CRTdm Communications software and uploading those settings to the data logger. Refer to the "Appendix" of this special instruction under the topic "Configuration Information" and see Tables 7 through 11 for information regarding specific parameters.

Note: The four system operation LED's on the front of the exhaust monitor must be monitored for routine maintenance. See Tables 1 and 2.

Exhaust Monitor System Operation LED's

Table 1

System Operation LED's and Information
System Status	Will blink once every 2 seconds indicating adequate power supply and normal operation
Over Pressure Alarm	ON if back pressure exceeds set limits OFF during normal operation
Over Temperature Alarm	ON if exhaust temperature exceeds set limit OFF during normal operation
System Problem	ON if the exhaust monitor detects a problem with a sensor OFF during normal operation

Basic Exhaust Monitor Alarm Diagnosis

In the event of an alarm, one or both of the LED's in the remote LED display will illuminate. In addition, LED's in the exhaust monitor will also illuminate.

The yellow LED in the remote LED display can indicate one or more of the following alarms:

• Over Temperature: High exhaust temperature was detected

• Over Pressure Warning: Back pressure is high

• Temperature Probe Failure: Probe has either shorted or the circuit is open

• Pressure Failure: The extension tube is broken or cracked, water has accumulated in the extension tube, or the pressure transducer needs attention.

• Exhaust Monitor Power Failure: If the exhaust monitor fails and power is still connected, the yellow LED illuminates in the remote LED display.

The red LED in the remote LED display only indicates when the back pressure is exceeding engine manufacturer's specifications. The engine must be shut down whenever it is safe to do so to prevent damage to the engine or to the DPF system.

In the event a LED illuminates in the remote LED display, consult Table 2 for very basic exhaust monitor alarm analysis. It is not intended to be used to determine the cause of a exhaust monitor alarm. The CRTdm Communications software must be used in conjunction with the LED's to diagnose a exhaust monitor alarm. If you do not have the CRTdm Communications software you must contact Caterpillar to assist in diagnosing exhaust monitor alarms.

Table 2

Alarm Events
LED Illuminated on Remote LED Display	LED Illuminated on Exhaust Monitor	Solution
Yellow	The Green LED by "System Status" is not flashing.	The exhaust monitor has no power. If there was no noticeable loss of engine power the machine may be safely driven back to the maintenance yard.
Yellow	Green LED by "System Status" is flashing and the Red LED by "System Problem" is ON.	One or more of the sensors providing data to the exhaust monitor has malfunctioned. Alert maintenance. The machine can be safely driven back to the maintenance facility.
Yellow	Green LED by "System Status" is flashing, Red LED by "Over-Temp" is ON, and the Red LED by "System Problem" is ON.	The exhaust temperature probe has malfunctioned. Alert maintenance. The machine can be safely driven back to the maintenance facility.
Yellow	Green LED by "System Status" is flashing and the Red "Over-Temp" LED is ON (no "System Problem" LED).	The exhaust temperature is too high. Alert maintenance. The machine can be safely driven back to the maintenance facility.
Yellow or Red	Green LED by "System Status" is flashing, and the Red "Over-Pressure" LED is ON.	The exhaust backpressure has exceeded operational limits. If the Yellow remote display LED is ON and the exhaust monitor "Over-Pressure" LED is ON, the filter requires maintenance as soon as possible. If the Red remote display lamp is ON and the exhaust monitor "Over-Pressure" LED is ON, the filter requires maintenance immediately and the machine must be taken out of service immediately.

Note: Any alarm events must be investigated immediately. Failure to do so may result in severe damage to the DPF or to the engine. Failure to diagnose any alarm events may void the warranty on the DPF or the exhaust monitor.

Contact Information

For further information on installation, operation, or troubleshooting, contact Caterpillar at the following website:

http://www.cat.com

Specifications

Exhaust Monitor Electro-Mechanical

Table 3

Housing	Metallic enclosure, near weatherproof seal, with sealing gland type fittings for wire egress.
Dimensions	10 x 6 x 3.5 with a tab/flange at each end for surface mounting.
Wiring Connections	Via weather pack and mini Type-K connectors on 3 separate pigtails. No user serviceable connectors are inside the enclosure.
Wiring Egress	Sealing gland type fittings. Sealed serial connection on electronics module cover.
Pressure Connection	Via - 18 NPT fitting directly onto integral pressure transducer.
Ambient Operating Temperature	−30 to 85 °C (−22 to 185 °F)

Exhaust Monitor Electrical

Table 4

Supply Voltage	Input range 12 to 24 VDC
Supply Current	50mA average current, 150mA max current, including all sensor excitation.
Cold Junction Compensation (CJC)	Integral via on board sensor at thermocouple connection point. CJC accuracy to add less than +/- 1.5 °C error over specified exhaust monitor ambient operating range; (typical will be less than +/- 0.6 °C)
ADC Resolution	10 bit unipolar; will result in apx 2 °C (36 °F) resolution for temperature and 0.1 inch Hg for pressure.
ADC Accuracy	Max (over temp): +/- 4 bits%.
System Accuracy	Temperature Error Max: +/- 5 °C (typical +/- 2 °C). Pressure Error: +/- 1.5% typical, 3% max.
Sample Capacity	The exhaust monitor is capable of storing approximately 260,000 records in internal memory. Dynamic allocation of memory space will be implemented to allow for asynchronous event storage (e.g. alarms).
RTC	Integral real-time clock with 10 year life expectancy lithium cell backup. Ambient temperature ( 25 °C (77 °F)) accuracy of +/- 30 seconds/month.
Glitch Recovery	The exhaust monitor microprocessor will be equipped with a hardware watch dog timer to restore normal operation in the event of a system upset.
Alarm Outputs	Two outputs. Alarm 1 is an open collector transistor output. Alarm 2 is a relay output. The normally closed contacts of this relay are used to add a level of fail-safe integrity to the system in the event of a system power failure. The relay will short Terminal strip TS2, Position 4 to ground upon alarm condition or in the event of a power failure of the exhaust monitor.
Serial Data Port	Multi-wire serial interface for connection to a PC. A fixed baud rate of 115K/baud is supported.
Software Restart	Upon interruption and re-application of power, the exhaust monitor will commence normal operation including data logging and alarm functions.

Pressure Transducer

Table 5

Housing	Cylindrical machined 316 SS housing. Unit will be contained within the exhaust monitor.
Diaphragm	316L
Operating Temperature Range	−40° to 125 °C (−40 to 257 °F)
Shock	100 G for 11mSec.
Vibration	10G at 20-2000 Hz.
Lifetime	1 million cycles.
Temperature Compensated Range	−10° to 85 °C (14° to 185 °F)
FS Range	0 - 20 inch Hg (0-10 PSIG) suggested. 140 kPa (20 psi) Proof/ Max. As deployed in exhaust monitor, the usable pressure range is 0 to 20 inch Hg.
Accuracy	Type: +/- 1.5%FS over temp; Max; +/-3%FS.
Pressure Connection	Via - 18 NPT fitting directly onto integral pressure transducer.
Supply Power	Power will be supplied through the exhaust monitor. The power supply will be pre-regulated and surge protected.

Temperature Sensor

Table 6

Type	"K" Thermocouple
Package	1/8 inch dia x 8 inch long Inconel 600 insertion probe compatible with Swagelok type compression fitting. Ungrounded thermocouple in hi-temp magnesium oxide insulator with MGO cement cap. Provided with 6.1 m (20 ft) electrically shielded teflon leads with 0.9 m (3 ft) of spiral armor at probe end. Lead rated 260 °C (500 °F) continuous. Probe tip rated 1000 °C (1832 °F) continuous.
Temperature Range (Withstand)	−100° to 1000 °C (−148° to 1832 °F) continuous.
Temperature Range (Operational)	0° to 1000 °C (32° to 1832 °F)
Sensor Accuracy	Special Limits TC wire used: +/- 1.1 °C or +/- 0.4%rdg whichever is greater over range 0° to 1000 °C (32° to 1832 °F).

Appendix

Configuration Information

Table 7

Over-Temp
Inlet Over-Temperature Alarm
	Condition	Expected Value
	Enable Alarm	Yes
	Log Alarm Transitions	Yes
	Active Output During Alarm	Output 1
	Output function	ON only during alarm
	Assert Alarm	Above 650 °C (1202 °F)
	Hysteresis	20 °C (68 °F)
	Upon Over Temperature extend alarm for 60 seconds

Table 8

Over-Pres
Over-Pressure Warning
	Condition	Expected Value
	Enable Alarm	Yes
	Log Alarm Transitions	Yes
	Active Output During Alarm	Output 1
	Output Function	ON only during alarm
	Assert Alarm when the measured pressure exceeds 7" of Hg for 5% of the time during a 60 min measurement interval
Over-Pressure Alarm
	Condition	Expected Value
	Enable Alarm	Yes
	Log Alarm Transitions	Yes
	Active Output During Alarm	Output 2
	Output Function	Latched ON upon alarm
	Assert alarm when the measured pressure exceeds 8" of Hg for 5% of the time during a 60 min measurement interval

Table 9

TC-Fail (1)
Open Thermocouple Detect
	Condition	Expected Value
	Enable Alarm	Yes
	Log Alarm Transitions	Yes
	Output During Alarm	Output 1
	Output Function	Latched ON upon alarm
	Assert alarm if measured temperature is above 1000 °C (1832 °F)
Shorted Thermocouple Detect
	Condition	Expected Value
	Enable Alarm	Yes
	Log Alarm Transitions	Yes
	Output During Alarm	Output 1
	Output Function	Latched ON upon alarm
	Assert alarm if pressure is greater than 1" of Hg for 10 min and measured temperature does not exceed 120 °C (248 °F)

( 1 )

Output selection applies to both open and shorted alarms

Table 10

Pressure Sensor Fail
No Change Alarm
	Condition	Expected Value
	Enable Alarm	Yes
	Log Alarm Transitions	Yes
	Active Outputs During Alarm	Output 1
	Output Function	Latched ON upon Alarm
	Assert alarm if exhaust temperature is above 250 °C (482 °F) for 10 min and the pressure doesn't change by at least 0.25" of Hg
Negative Pressure Alarm
	Condition	Expected Value
	Enable Alarm	Yes
	Log Alarm Transitions	Yes
	Active Output During Alarm	Output 1
	Output Function	Latched ON during alarm
	Assert Alarm if temperature is above 200 °C (392 °F) for 10 min and the pressure is less than −1" of Hg

Table 11

Logging Strategy
Memory Utilization	Rotary Memory
Logging Threshold	100 °C (212 °F)
Record Interval	10 min