Cat® Grade Control Calibration and Measure-Up Procedure for Certain Track-Type Tractors {7220} Caterpillar

Track-Type Tractor

D8T (S/N: AW41-UP)

Introduction

This Special Instruction will aid in the Cat^® Grade Control calibration and measure-up procedure for certain Track-Type Tractors.

Reference

Reference: Refer to Systems Operation Troubleshooting Testing and Adjusting, M0098327 , "Cat^® Grade Control for the D8T Track- Type Tractors"

Reference: Refer to Operation and Maintenance Manual , M0098339, "Cat^® Grade Control for the D8T Track-Type Tractors 3D" topics , "Diagnostics - View", "Flashing Messages", "Troubleshooting Techniques", "Troubleshooting Common Problems", "Full Screen Messages", and "Settings - Save".

Reference: Refer to Special Instruction, M0092319, "Set-Up and Measure-Up Process of a Universal Total Station (UTS) for Cat^® Grade Control"

Reference: Refer to the Schematic, UENR7739, "D8T Track-Type Tractor Electrical System".

Safety

Work safely. Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs.

A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools to perform these functions properly.

Safety precautions and warnings are provided in this instruction and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard.

Therefore, the warnings in this publication and the warnings that are on the product are not all inclusive. Ensure that any tool, procedure, work method, or operating technique you use that is not recommended by Caterpillar is safe.

Ensure that the product will not be damaged or the product will not be made unsafe by the operation, lubrication, maintenance, or repair procedures used.

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Do not operate or work on this machine unless you have read and understand the instructions and warnings in the Operation and Maintenance Manuals. Failure to follow the instructions or heed the warnings could result in injury or death. Contact your Cat dealer for replacement manuals. Proper care is your responsibility.

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Unexpected blade movement may occur when the blade control system is in automatic mode. Unexpected blade movements that occur while mounting or dismounting the machine may result in injury or death. Before dismounting the machine, always place the automatic blade control system into manual mode and follow the machine parking procedures specified in the machine Operation Manual.

• Only mount the machine and dismount the machine at locations that have steps and/or handholds.

• Inspect the steps and the handholds before mounting and dismounting. Clean the steps and the handholds, if necessary. Repair the steps and the handholds, if necessary.

Illustration 1	g03840524

• Face the machine when you are mounting and dismounting.

• Maintain a three-point contact with the steps and the handholds. Three-point contact is maintained when two feet and one hand are in contact or one foot and two hands are in contact.

• Never get on a moving machine or off a moving machine.

• Never jump off the machine.

• Do not try to climb on the machine or climb off the machine when you are carrying tools or supplies. Use a hand line to pull equipment up to the operators platform.

• Do not use any of the controls as handholds as you are climbing into the machine or exiting the machine .

Note: Caterpillar recommends that each customer conducts a risk assessment for remote control operation and establish layers of protection in and around the area of the remote controlled machine and establish safe job site procedures. Examples may include personnel training, warning signs, and barricades.

Note: Prior to operation of the machine read the Operation and Maintenance Manual.

Required Parts

The required parts are listed in Table 1. Items in Table 1 are available through your SITECH dealer or local survey equipment retailer.

Note: The GNSS data radio is not included as part of the Grade Control package. A device for acquiring GNSS corrections for RTK-Fixed accuracy must be purchased separately depending on the requirements and regulations of each work site. Ensure that this device is installed and configured according to the suppliers specifications. Contact your Technical Communicator or SiTECH Dealer for possible radio solutions.

Note: GNSS receivers are not installed on top of the Cab when the receivers are shipped from the factory. GNSS Receivers are shipped inside the cab or in the attachment shipping container and must be installed by the dealer prior to customer delivery.

Required Tools

Items in the following list are available through Cat dealer.

Note: Display firmware and Implement ECM software should be updated to latest available released version prior to performing the measure up procedure.

Calibration and Measure-up Procedure

Machines delivered from the factory arrive without the configured blade attached and it is necessary to complete the calibrations described in this document. In cases of component replacement/adjustment and changes in the hydraulic system, a complete recalibration of the Cat Grade Control System may also become necessary. This document contains the complete Cat Grade Control Calibration and Measure-Up information.

The types of calibrations are listed below:

• Blade Solenoid Calibrations

• Tool Automation Implement Valve Calibration

• The Inertial Measuring Unit (IMU) Calibration

The Blade Solenoid calibrations are completed at the factory. However for best system performance, Caterpillar recommends completing calibrations with blade installed and prior to the Tool Automation Implement Valve calibration.

The Tool Automation Implement Valve calibration is required for the Cat Grade Control system. Tool Automation Implement Valve calibration maps the blade movement and relation to the hydraulic system. For the best system performance, complete the Tool Automation Implement Valve Calibration immediately following the Blade Solenoid Calibrations and with the blade installed.

The Inertial Measuring Unit (IMU) calibration is often called the Slope Sensor or Angle Sensor calibration. Complete this IMU calibration prior to measuring the blade cutting edge relationship with the GNSS receivers using the coordinate measure-up process for the machine measurements and with the blade installed.

The Measure-Up Process for the machine measurements of the Cat Grade Control system is required. This process allows the system to calculate the machine measurements between the coordinate locations of two GNSS antenna points and the six cutting edge points. The system then relates those measurements to sensor values. A Trimble Universal Tracking System (UTS) or a similar total station is necessary to measure the coordinate location of the antenna points and cutting edge points.

Several of the Cat Grade Control calibrations can only be completed using the Cat^® Electronic Technician (Cat ET) . These calibrations are integral to the system and cannot be viewed or completed using the onboard CB460 Cat Grade Control 3D display. These calibrations are related to the hydraulic system interaction with the Cat Grade Control system.

Required Calibrations via Cat^® Electronic Technician (Cat ET)

Note: Cat ET Version 2016B is required for Position Sensing Cylinder Calibrations.

The following calibrations for the specified component are all completed at the factory:

• Blade Solenoid

- Blade Raise Solenoid

- Blade Lower Solenoid

- Blade Tilt Left Solenoid

- Blade Tilt Right Solenoid

• Grade Control Valve

- Grade Control Valve Calibration/ Tool Automation Implement Valve Calibration

Recommended Order

Complete the calibrations in the following order:

• Blade Solenoid Calibrations (use Cat ET)

• Tool Automation Implement Valve Calibration (use Cat ET or Premium Monitoring System)

• Inertial Measuring Unit Calibration (use CB460 Grade Control Display)

• Machine Measure-Up (use CB460 Grade Control Display)

Note: The calibration and measure-up procedure must be completed in the specified order. Do not skip steps. Failure to complete the steps in sequence may cause inaccuracy of the system and require repeating the procedure to resolve.

Blade Solenoid Calibrations

The Blade Solenoid Calibrations are required by any modern Caterpillar track type tractor regardless of whether the machine has the Cat Grade Control system integrated. The purpose of these calibrations is to determine the electrical current characteristics for each solenoid movement. This can vary depending on hydraulic fluid temperature, wear occurring on solenoids and valve, and the blade mass mounted on the machine. This is why it is critical to achieve the appropriate operating temperature before the calibration records the solenoid characteristics.

The Blade Solenoid Calibrations can only be completed using Cat ET and not through the CB460 Cat Grade Control display.

Connect Cat ET 2015A or newer to the machine service port through a COM adapter. Once the connection is completed, the service person may interface with the machine system settings and calibrations.

Follow the below procedure to perform the Blade Solenoid Calibrations:

1. Select "Service" from the toolbar and select "Calibrations" from the drop-down menu.
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   Illustration 2	g03815774

2. Double-click "Blade Solenoid Calibration" or highlight "Blade Solenoid Calibration" and click "Start".
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   Illustration 3	g03815775

3. Read and acknowledge the warning associated with this calibration.
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4. Select the desired solenoid calibrations (typically all of them) and click the "Begin" button.
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   Illustration 5	g03815779

5. Complete the calibration setup conditions:

   • Set the parking brake.

   • Engine must be running and set to high idle.

   • Implement Lockout Switch must be in the Not Locked position.

   • Hydraulic Oil Temperature must be between 50° C (122° F) and 80° C (176° F) (Hydraulic Oil may be heated by stalling the cylinders and working the cylinders back and forth through their working range).

   • Position the blade solidly on the ground.
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   Illustration 6	g03815782

6. Release the blade control handle, if held, and allow it to return to its neutral position before clicking the "Next >" button.
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   Illustration 8	g03815789

7. Move and hold the Blade Control Handle into the full raise position.

   Note: The system will calibrate the solenoid while the blade control handle is being held. Illustration 8 shows "CALIBRATING" during this part of the process.

   Note: During this part of the calibration, the current values for the Blade Solenoid Current shown on the Cat ET screen will ramp up through the prescribed range.

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   Illustration 9	g03815790

8. When the step has been completed (indicated by the check mark for the step in Cat ET, the Blade Control Handle should be released. Click the "Next >" button to continue.
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   Illustration 10	g03816345

9. The specific Blade Solenoid Calibration should complete successfully and the dialog to continue to the next listed Blade Solenoid Calibration should be shown. Click the "Continue" button to the next Blade Solenoid Calibration.

   Note: The remaining Blade Solenoid Calibrations are similar to the Blade Raise Solenoid Calibration shown in Step 5 through Step 9.

10. Repeat similar steps as shown in Steps 5 -9 for the remaining listed Blade Solenoid Calibrations for each solenoid and Blade Control Handle function.
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    Illustration 11	g03816348

11. When all the listed Blade Solenoid Calibrations have been successfully completed, click the "Finish" button to exit the successfully completed calibrations.

    Note: Machines configured with an S/SU blade will only show the Blade Raise Solenoid, Blade Lower Solenoid, Blade Tilt Left Solenoid, and Blade Tilt Right Solenoid Calibrations.

Grade Control Valve / Tool Automation Implement Valve Calibration

The Grade Control Valve / Tool Automation Implement Valve Calibration is necessary for the Cat Grade Control system. The Tool Automation Implement Valve Calibration provides customized Cat Grade Control hydraulic system mapping between the valve solenoids and the physical blade movement. This calibration utilizes the Blade Solenoid Calibrations completed previously. Because the Tool Automation Implement Valve Calibration results are dependent on the Blade Solenoid Calibrations, Caterpillar recommends that the Blade Solenoid Calibrations be completed immediately preceding the Tool Automation Calibration for optimum Cat Grade Control performance.

Note: Completing the Blade Solenoid Calibrations immediately preceding the Tool Automation Implement Valve Calibration minimizes the system response differences due to the calibrations having been completed on hydraulic fluid at different temperatures and valve or solenoid wear.

The Tool Automation Implement Valve Calibration should be completed using Cat ET 2015B or newer.

Note: The Tool Automation Implement Valve Calibration will move the blade automatically once initiated. A portion of the calibration will push the blade down into the ground and lift the machine. See the warning description when the calibration is started.

The Tool Automation Implement Calibration shown in Cat ET is the same calibration as the Grade Control Valve Calibration that is available in the G7P machine display. The G7P machine display is included on the latest D8T models with the new transmission.

Follow the below procedure to perform the Grade Control Valve / Tool Automation Implement Valve Calibration:

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Illustration 12	g03816351

1. To start the Tool Automation Implement Valve Calibration, select "Service" from the toolbar and select "Calibrations" from the drop-down menu. Cat ET will populate the calibrations that are available and the Tool Automation Implement Valve Calibration can be started by double-clicking the name or highlighting it and pressing start in the lower left-hand corner of the screen.
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   Illustration 13	g03816352

2. Read and Acknowledge the warning associated with this calibration by clicking the OK button.

   Do not proceed with this calibration unless you have read and understand the following instructions and warnings. Failure to follow the instructions or heed the warning could result in injury or death.

   • Automatic Lowering may Cause the Front/Rear of the machine to raise off the ground.

   • This calibration may be aborted with any blade control lever command or by setting the implement lockout switch to the lockout position

   Before Calibrating follow the steps below:

   • Park the machine in an open area on level ground.

   • Provide adequate clearance for full tilt and lift blade functions.

   • Beware of hazards such as wires, fences.

   • Clear all personnel from the machine and from the area.

   • Check visibility and adjust mirrors for best vision close to the machine.

   • Before leaving the machine or allowing others to approach the area, ensure that the park brake is on and all implements are neutralized and locked out.

   • Fasten the seat belt securely and remain in the seat throughout the procedure.
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   Illustration 14	g03816355

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   Illustration 15	g03816359

3. Setup calibration conditions listed:

   • Place the machine in an open area on firm ground and probably not concrete where the blade driving into the ground and lifting the machine tracks will not damage the tractor or surface.

   • Verify that the implement solenoid calibrations (Blade Solenoid Calibrations) are complete.

   • Verify that the position sensing cylinders are installed and the calibrations (Position Sensing Cylinder Calibrations) are complete.

   • Set the Parking Brake.

   • Switch the Implement Lockout Switch to the Not Locked Position.

   • Verify that the Hydraulic Temperature is between 50 deg C and 80 deg C.

   • Raise the ripper fully.

   • Set Engine to High Idle.

   Note: The calibration will move the blade through its entire range of motion.

   Note: If the setup conditions are not satisfied when the "Next >" button is clicked, the calibration may trigger an error code specifying which setup condition is out of the required state. Illustration 15 shows that the Hydraulic Oil Temperature is Too Low, the Implement Lockout Switch is On, and the Engine RPM is set Too Low to meet the conditions.

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   Illustration 16	g03816360

4. Level the blade (eyeball level) and position it slightly (approximately 1-5 cm) above the ground and click the "Next >" button.
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   Illustration 17	g03816361

5. Read and Acknowledge the warning by clicking the "Accept" button.
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   Illustration 19	g03816388

6. Click the "Next >" button and then move the blade handle to the full lower position and return it to the center position. Leave the blade handle lever in the center position while the calibration automatically performed.

   Note: The calibration may be halted at any time in this step by moving the blade handle or clicking the "Cancel" button.

   Note: After completing the blade lift and lower portion of the calibration, the system maps the tilt right characteristics at both high and low speed blade movements and tilt left characteristics at both high and low speed blade movements.

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   Illustration 20	g03816396

7. Click the "Finish" button as the Tool Automation Implement Valve Calibration should have completed successfully.

Set up the CB460 Grade Control Display

The CB460 Grade Control display supports many different machine options. The Cat Grade Control system stores some of the configured machine settings on the CB460 Grade Control displays and some on theCaterpillar Electronic Control Modules (ECM).

On the CB460 Grade Control display, the Machine Settings are stored within a.MCH file that can be saved and exported. The CB460 Grade Control display offers a display wizard for changing these parameters when the display is in Manager Mode.

Follow the below procedure to set up the CB460 Grade Control display:

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Illustration 21	g03816952

1. For the D8T Cat Grade Control 3D machines, the "Dozer (TTT)" selection in the Machine Type parameter screen must be selected.
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   Illustration 22	g03865501

2. Machines have specific sensor configurations and tuning values that are designed for each model. There are a lot of similarities between the D8T models but there are separate options for the D8T to account for the difference in hydraulic system and platform characteristics. Select "Cat D8T" for both T4i and T4f D8T models.
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   Illustration 23	g03816957

3. All Cat Grade Control tractors with dual GNSS receivers are "Machine Cab Left and Right" installations.
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   Illustration 24	g03816974

4. All Cat Grade Control 3D machines require GNSS data corrections to obtain machine control and guidance level accuracy. There are some different options available to obtain these data corrections on the machine. Configure the machine system based on the radio and site-specific requirements.
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   Illustration 25	g03816998

5. The Cat Grade Control can be configured to provide only the indication of the blade position, but the system is intended to operate in full automatic control of the blade by selecting "Auto - Lift/Tilt".
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   Illustration 26	g03817011

6. The Cat Grade Control system operates a little differently than some other grade control systems. When automatic control is activated, the control will not drive the blade until the blade engages the design.
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   Illustration 27	g03817013

7. The option keys that are required by the Cat Grade Control system on a track type tractor are Track Type Tractor - 3D Automatics. All CB460 Grade Control displays included in the Cat Grade Control system have a dedicated display Product Line "Cat Grade Control".

Install the 386-7311 Antenna

Follow the below procedure to install the Antenna:

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Illustration 28	g03614254

1. Use four 8T-4137 Bolts and four 8T-4121 Hard Washer for each antenna. Torque the bolts to 46 N·m (34 lb ft).
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   Illustration 29	g03619839
   (1) Cable fitting through hole

2. Install the 362-4311 Cable As and 393-0083 Antenna Cable AS to the antennas.

Calibrating the Inertial Measuring Unit (IMU/Angle Sensor)

Before completing the machine Measure-Up procedure, it is essential to successfully complete the Inertial Measuring Unit (IMU) Calibration. This calibration procedure will calibrate the onboard IMU also sometimes called the Angle Sensor.

Note: If a valid IMU calibration has not been completed at the time of the machine measure-up procedure, the dimension translation from the entered coordinates to the blade position dimensions will not be calculated properly. An accurate and complete IMU calibration must be completed prior to the machine measure-up procedure.

The calibration is completed by moving the machine through three positions and capturing the sensor data at each location a number of times. Three positions capture data with the machine facing one direction and the remaining two or three sensor data captures are completed on those same positions but with the machine facing in the opposite direction.

Illustration 30	g03779310

Caterpillar recommends that the IMU calibration be completed on a hard and firm surface, preferably concrete, because soft ground conditions lead to less repeatable readings that can impact the overall accuracy of the IMU calibration. If concrete is not available, ensure that the track disturbance of the ground surface is minimized for best calibration results.

Note: The ground should be relatively close to level and even but it does not have to be perfectly level and even as long as the tracks/machine do not rock in the different positions.

Illustration 31	g03779313

The Machine Inclination Sensing Device Calibration can be found in the Configuration Menu on the CB460 display under the Calibrate Sensor selection. Refer to Illustration 31.

Follow the below procedure to calibrate the Inertial Measuring Unit:

1. Position the machine and blade on a firm flat surface, which will allow the machine to be tracked and turned around for some calibrations.

2. Ensure the pre-delivery inspection and calibrations are complete including the "Control Handle" and "Implement Solenoid" calibrations in Cat ET or the Advisor display.

   Note: The machine will request most these setup conditions for each of the positions where it captures sensor data.

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   Illustration 32	g03779316

3. The calibration screen on the CB460 will show various setup conditions.

   Set up the machine according to the instructions shown in Illustration 32:

   • Select a smooth hard surface over three machine lengths long.

   • Park at the start of the smooth hard surface.

   • Rest the blade and implements on the ground.

   • Set engine speed to low idle.

   • Set the parking brake and implement lock-out switch.

   Note: Caterpillar does not recommend using the Factory Defaults for the Inclination Sensing Unit Calibration. Using the Factory Defaults will lead to inaccurate machine guidance.

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   Illustration 33	g03779318

4. The machine should be positioned so that it has enough room to proceed in a straight line for some distance in order to obtain three different positions. When the machine travels in a straight line, this helps ensure that the matching sensor data capture steps can capture the data when the machine is facing in the opposite direction.
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   Illustration 34	g03779319

5. With the machine positioned in the first position, mark the ground using definite points from the tractor such as the center of the idler and rear sprocket or the front and rear tracks.

   Note: Marking the position is important for re-aligning the machine when capturing the reverse facing data points for the IMU sensor.

   When the operator has completed Steps 1 through 5 and is ready for the system to capture the reading from the IMU, press the arrow button.

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   Illustration 35	g03779322

6. Move the machine a full length of the machine in a straight line and complete the setup instructions. Refer to Illustration 35.
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   Illustration 36	g03779324

7. Mark the machine position off the machine as discussed in Step 5.

   Note: It is helpful to indicate the forward and back position as well as the side-to-side position. Marking the ground with a can of paint in the form of crosshairs is sufficiently accurate.

   Note: The system verifies that the setup conditions are met before the IMU actually acquires sensor data for the machine position and orientation in this step.

   Once the system has acquired a sufficient amount of IMU data for the position, the calibration will automatically proceed.

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   Illustration 37	g03779333

8. Move the machine a full length of the machine in a straight line and complete the setup instructions. Refer to Illustration 37.
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   Illustration 38	g03779334

9. Mark the machine position off the machine as discussed previously in Step 5. Refer to Illustration 38.

   Note: It is helpful to indicate the forward and back position as well as the side-to-side position. Marking the ground with a can of paint in the form of crosshairs is sufficiently accurate.

   Note: The system verifies that the setup conditions are met before the IMU actually acquires sensor data for the machine position and orientation in this step.

   Once the system has acquired a sufficient amount of IMU data for the position, the calibration will automatically proceed.

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   Illustration 39	g03779337

10. Move the machine far enough forward so that it can be turned around without disturbing the last captured machine location.

11. Once the machine is far enough from the Position #3 to safely turn without disturbing the position, orient the machine to face 180 degrees from the previous direction and align it so that it can pass through the previously marked positions traveling in a straight line.

    Note: The calibration will now have the operator move the machine back through the three marked positions. The machine will arrive at Position #3 facing in the opposite direction first and proceed to Position #2 and Position #1 sequentially.

12. Move the machine so that it is aligned with the marks made for Position #3. Make sure that the machine is facing in the opposite direction from the previous steps.

13. Set up the machine according to the instructions:

    • Stop when the centers of the front Idler wheels are aligned with marks as shown in Illustration 39.

    • Rest the blade on the ground.

    • Set engine speed to low idle.

    • Set the parking brake and implement lock-out switch.

    Note: Align tracks and sprocket/idler positions according to the Illustration 39. The center of the idlers should be over the same locations for machine positions with the machine facing in opposite directions

    Note: The machine will request the blade on ground, engine speed at low idle, parking brake On, and implement lock-out On setup conditions for each of the positions where it captures sensor data.

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    Illustration 40	g03779341

14. Proceed using the arrow button. Refer to Illustration 40. The system verifies that the setup conditions are met before the IMU actually acquires sensor data for the machine position and orientation in this step.

    Once the system has acquired a sufficient amount of IMU data for the position, the calibration will automatically proceed.

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    Illustration 41	g03779343

15. Move the machine so that it is aligned with the marks made for Position #2. Make sure that the machine is facing in the opposite direction from the previous IMU data capture for Position #2. Refer to Illustration 41.
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    Illustration 42	g03779346

16. Press the arrow button. Refer to Illustration 42. The system verifies that the setup conditions are met before the IMU actually acquires sensor data for the machine position and orientation in this step.

    Once the system has acquired a sufficient amount of IMU data for the position, the calibration will automatically proceed.

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    Illustration 43	g03811056

17. If the captured IMU data from the two directions at Position #2 and Position #3 meets the accuracy requirements for the calibration result, the calibration will complete successfully without capturing data from the final steps at Position #1. Refer to Illustration 43.
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    Illustration 44	g03779358

18. If the captured IMU data from the two directions at Position #2 and Position #3 does not meet the accuracy requirements for the calibration, the calibration will proceed to the final steps at Position #1.
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    Illustration 45	g03779359

19. Press the arrow button. Refer to Illustration 45. The system verifies that the setup conditions are met before the IMU actually acquires sensor data for the machine position and orientation in this step.

    Once the system has acquired a sufficient amount of IMU data for the position, the calibration will automatically proceed.

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    Illustration 46	g03779361

20. As long as the captured IMU data with the final position meets the accuracy requirements for the calibration result, the calibration will complete successfully. Refer to Illustration 46 If the accuracy requirements are not met, the calibration will be unsuccessful, and have to be repeated.

    If at any point in time a diagnostic becomes active on the Cat Grade Control system, the calibration will abort. There are some diagnostics unrelated to the Cat Grade Control system that will not cause the system to abort the calibration.

    An accurate IMU calibration is critical to accurate machine control and guidance. Before the machine measure-up can be completed using a universal tracking station, an IMU calibration is required. Without an IMU calibration, the machine measure-up process will not calculate the correct machine dimensions relating the GNSS antenna positions to the blade cutting edge.

    The IMU calibration can be validated by positioning the machine and verifying that positive values for machine pitch and/or roll change to negative values with the same magnitude when the machine faces the opposite direction (180 deg). Failing to position the machine in the same exact position, exact opposite direction, or on soft, unstable ground, can impact the accuracy of this validation exercise.

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    Illustration 47	g06370215
    (1) Antenna (2) Antenna (3) Blade edge (4) Blade cutting edge (5) Bolt center (6) Bolt center (7) Blade cutting edge (8) Blade edge

    Note: Points 3 and 8 are at blade edge. Points 5 and 6 are at bolt center

21. Use the onboard CB460 Grade Control display to service the system during the machine measure-up. The machine must be running for the first few steps of the measure-up process.
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    Illustration 48	g06370235
    (D1) Horizontal distance between the top center of the left and right blade cylinder rods

22. Measure the horizontal distance (D1) in millimeters between the top center of the left blade cylinder rod to the top center of the right cylinder rod. Refer to Illustration 48. The measurements should be taken just above where the rod attaches to the ball mounts at the back of the blade.

23. Enter the measurements in the "Lift Cylinder Connection Point Straight Line Distance" Length 9 value.

    Note: This measurement may vary from blade to blade. The D8T SU blade measurement is approximately 1255.0 mm (49.40 inch)

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    Illustration 49	g03614044

24. Measure the height of the track grouser from the edge to the face of the shoe. Refer to the Illustration 49. Enter the measurements in the "Grouser Height" value using the CB460 Grade Control display Machine Measurements menu.

    Note: Grouser height should be the amount of grouser above ground. If the grousers fully penetrate the ground surface, the measurement should be zero.

    The measure-up procedure requires that the system can read the position sensing cylinders (PSC) and the inclination sensor date when the measurements from the measure-up procedure are entered in the system. The system correlates the measurements to the sensor data, which is why it is important that the machine, once positioned, does not move or drift until the data is entered into the CB460 Grade Control display.

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    Illustration 50	g06274380

    Note: Numbered target locations for measuring required coordinates points for the machine measure-up.

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    Illustration 51	g03797664

25. To start the measure-up wizard on the CB460 Grade Control display, do the following steps:

    1. Press the "Menu" button to access the Setup Menu - Configuration.

    2. Press the "Installation" button to access the Setup Menu - Installation.

    3. Scroll down and select "Machine Measurements".

    4. Start the measure-up wizard by clicking "Enter Machine Measurements".
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    Illustration 52	g03779365

26. Position the machine on level ground.

    • Lift the blade off the ground so that the blade pitch forward or back without engaging the ground. This can typically be done with common blade with 30.0 to 40.0 cm (11.81 to 15.75 inch) of ground clearance.

    Note: Both the IMU calibration and the PSC calibrations are required before the measure-up process can be completed.

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    Illustration 53	g03614037

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    Illustration 54	g03811008
    Implement Joystick

27. Perform each step of Preparation - Blade Pitch in the order displayed. Refer to Illustration 53.

    These steps will position the blade pitch to a known and repeatable pitch location for the machine measure-up. The system can then reset the blade pitch to this measure-up position to gain best guidance accuracy.

    • Selecting Grade Control Mode on the keypad is not necessary, if the operator has entered the measure-up wizard in the CB460 Grade Control display.

    • Set the machine to High Idle for the blade pitch position to be reset accurately.

    • Press the inside push-button switch (Pitch Reset/Auto Blade Assist) on the Implement joystick to reset the blade pitch . Refer to Illustration 54.

    • Lower the blade and proceed with the measure-up process.

    • The engine can be turned OFF, but restore auxiliary power by turning the key to the ON position for running the CB460 Grade Control measure-up wizard.
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    Illustration 55	g03779367

28. After performing each step in "Preparation - Lower Blade" in the order displayed , press F6 softkey to advance to the next menu. This step is done to avoid potential error due to blade drifting between when measurements are taken and when the measurements are entered in to the CB460 Grade Control display.

    Note: The blade may be blocked with wooden blocks as long as there is no likelihood of the blade sinking into the ground.

    Note: The ECM will monitor the park brake , implement lockout, and the Cat Angle sensor until all the measurements are complete. If any of the three give an error, the ECM will send a message to the CB460 and the measurements entered thus far will be cleared and the program will return to the above screen.

Universal Total Station (UTS) Setup

Reference: Refer to Special Instruction, M0092319, "Set-Up and Measure-Up Process of a Universal Total Station (UTS) for Cat^® Grade Control"

Entering Machine Body Dimensions

Machine Body Dimensions are required for proper function of the Cat Grade Control System. The Machine Body Dimensions are used by the system to evaluate whether the machine is entering an avoidance zone. These values can only be entered through the CB460 Grade Control display.

Validate Machine Measurements

Follow the procedure below to validate the machine measurements:

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Illustration 56	g06262805
CGC TTT Measure-Up Dimensions

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Table 3

Machines	T4i D8T (FCT00114)	T4f D8T (JET00202)	T4f D9T {REX00302)
Left GPS antenna to cutting edge bolts
Height to cutting edge bolts	3.548 m (11.6404 ft)	3.540 m (11.6142 ft)	4.053 m (13.2972 ft)
Back from cutting edge bolts	4.952 m (16.2467 ft)	4.930 m (16.1745 ft)	4.660 mm (0.1835 inch)
In from left blade tip	1.508 m (4.9475 ft)	1.528 m (5.0131 ft)	1.713 m (5.6201 ft)
Right GPS antenna to cutting edge bolts
Height to cutting edge bolts	3.547 m (11.6371 ft)	3.551 m (11.6502 ft)	4.042 m (13.2612 ft)
Back from cutting edge bolts	4.949 m (16.2369 ft)	4.934 m (16.1877 ft)	4.662 m (15.2953 ft)
In from right blade tip	1.582 m (5.1903 ft)	1.564 m (5.1312 ft)	1.793 m (5.8826 ft)
Left GPS antenna to track
Height to bottom of track shoe	3.590 m (11.7782 ft)	3.594 m (11.7913 ft)	4.066 m (13.3399 ft)
Back from track pivot point (-=forward}	0.818 m (2.6837 ft)	0.818 m (2.6837 ft)	0.116 m (0.3806 ft)
In form outside edge of left track	0.967 m (3.1726 ft)	0.931 m (3.0545 ft)	1.017 m (3.3366 ft)
Left outside track to right outside track	2.693 m (8.8353 ft)	2.693 m (8.8353 ft)	2.860 m (9.3832 ft)
Blade
Blade Height	1.000 m (3.2808 ft)	1.000 m (3.2808 ft)	1.000 m (3.2808 ft)
Blade width between tips	3.917 m (12.8511 ft)	3.915 m (12.8445 ft)	4.334 m (14.2192 ft)
Cutting edge horizontal distance	0.067 m (0.2198 ft)	0.064 m (0.2010 ft)	0.066 m (0.2165 ft)
Cutting edge vertical distance	0.120 m (0.3937 ft)	0.111 m (0.3642 ft)	0.106 m (0.3478 ft)
Machine Measure-Up
Caterpillar PSC
Left position at time of measure-up	1.066 m (3.4974 ft)	1.073 m (3.5203 ft)	1.243 m (4.0781 ft)
Right position at time of measure-up	1.064 m (3.4908 ft)	1.088 m (3.5696 ft)	1.232 m (4.0420 ft)
Distance between lift rams	1.255 m (4.1175 ft)	1.255 m (4.1175 ft)	1.405 m (4.6096 ft)

1. View Machine Measurements menu can be used as a sanity check for validating calculated dimensions. Scroll through the menu to identify any gross errors due to measurements that were mis-keyed or entered with improper units.

   The Illustration 56 above provides examples of several tractor measurements for Cat Grade Control.

   Note: The dimensions shown in the attached table are for specific machines. Machine Measurements are dependent on track, shoe, undercarriage, and blade configurations as well as IMU calibration and assembly variability.

   Note: The dimensions in the attached document are for reference only and validating measurements produced from the measure-up process. Entering these values into a Cat Grade Control tractor will not produce good machine control and guidance results.

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   Illustration 57	g03614238

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   Illustration 58	g03614235

2. The Enter Machine Measurements "Edit" function can be used for validating calculated dimensions or editing selected dimensions.

   Note: This adjustment is not intended to replace the UTS measure-up. Changing dimensions in this menu can have unexpected results in grade accuracy, especially while operating on slopes. The best practice to correct for elevation errors is to repeat this entire procedure from start to finish.

   Note: If the machine dimensions are correct and the blade wear measurements are correct, the blade probably drifted during the measure-up. Blade drift will cause a difference between measured and sensed values. Reposition the blade, block the blade to prevent drift, and complete the measure-up procedure again. Completing the measure-up procedure again usually resolves any issues.

   Note: The values entered into the Machine Measurements wizard will remain editable until the Finish softkey is pressed (or the OK key when in the same screen). At that time all fields will be cleared.

   Note: "Edit" is only available in Manager Mode.

3. Press F4 "Factory Defaults" to advance to the "Machine Measurements - Calculated dimensions" screen described on Edit Dimensions , but with the factory default values restored and visible.

4. Pressing the F3 "Edit" or F4 "Factory Defaults" softkey will cancel the system monitoring of the machine-remain-stationary condition since this is not a requirement when editing calculated values.

5. The control points recorded on the Trimble controller can be exported to the root of a USB memory card. Use the following steps to export control points to a memory card :

   1. Insert the USB memory card into the USB port.

   2. Select "Work Orders".

   3. Select "Export/Import Data".

   4. Select "Export Points to CSV File".

   5. Select the coordinate order: P, N, E, Z, D. Include QA data and select "OK".

   6. Export point to a memory card. Now the .csv file has been saved to the root folder of the memory card successfully.

   7. Tap "OK" then "Escape/Close" back to the main menu or power down by tapping the green button at the lower left of the keypad.

   8. Remove the USB memory card.

   9. Power down the controller and UTS.
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   Illustration 59	g06369500
   CB460 display (1) LCD (2) Soft key labels (3) Soft keys (4) "Next key" (5) Zoom in (6) Zoom out (7) Escape key (8) Arrow keys (9) "OK" key (10) Light bar (11) Menu key (12) Power key (13) USB port

6. Ensure that the radio is configured to match the base station and is working properly. Refer to the supporting documentation from the radio supplier. Contact the site foreman, Cat Dealer GNSS specialist, or SiTECH for additional assistance.

7. Validate the blade wear measurement.

   1. Follow all safety procedures outlined in this manual and the machine Operation and Maintenance Manual. Be certain the blade is in the down position before performing the following procedure.
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      Illustration 60	g06274383

   2. With the blade of the machine in the down position on the ground, measure the height of the cutting edge to the center of the bolt holes. Refer to Illustration 60.
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      Illustration 61	g03614242

   3. From the "Setup Menu - Configuration" dialog, select the "Blade Wear" option. Refer to Illustration 61.
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      Illustration 62	g03614243

      Note: Be aware of the units. If the display is set up in metric units, the blade measurement must be entered in metric units. If the display is set up in feet, the blade measurement must be entered in tenths of feet.

   4. Verify that the blade wear measurement is correct. If the measurement is not correct, use the arrow keys to enter a value into the "Cutting Edge Height" field. Refer to Illustration 62.

      Note: Blade wear is calculated during the measure up. Error between the displayed blade wear value and the measured blade wear, indicates an error in a measure-up values entered. Double check values entered against values measured for key in mistakes or improper units. If the source of any gross error cannot be identified, the measure-up needs to be repeated.

   5. Perform one of the following actions:

      • Press the "OK" key to accept the changes and return to the "Setup Menu - Configuration" dialog.

      • Press the escape key in order to cancel any changes and return to the "Setup Menu - Configuration" dialog. The operator is asked to confirm that they do not want to save any changes.

   6. Press the escape key to exit the "Setup Menu - Configuration" dialog. The changes take effect immediately.

8. Validate the blade measure-up and system accuracy with rover checks.

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   In order to prevent personal injury during installation and removal of the GPS receivers, use an approved access system in order to reach the mounting locations of the GPS receivers at the top of the masts. Do not climb on the blade.

   1. Ensure that the acrylic targets are removed from the blade.

   2. Replace the 360 degree prism with the GNSS Antennae and ensure that it is securely installed and connected.

   3. Load a local design or create a design on the Cat Grade Control display which uses a .cfg file generated from the same site calibration file that is loaded on the GNSS rover that is being used to check accuracy.

      • Check diagnostics in the CB460 Grade Control display for connectivity.

      • Confirm in the CB460 Grade Control display that correction information is received from the base station.

      • Verify that the GNSS solution status shown in the CB460 Grade Control display GNSS diagnostic screen is "RTK Fixed".

      • Ensure the display diagnostic menu reports the "Communication Information Data" has a high integrity rating.

      • Ensure that the GNSS data radio is configured for the correct network ID/frequency.

      • Verify that correct design file or configuration file has been loaded onto the system.

      • Current correct design file or configuration file on machine matches that in the GNSS rover.

   4. Low Accuracy move should not be displayed with a dual GNSS system.
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      Illustration 63	g03614244

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      Illustration 64	g03614245

   5. Using the GNSS rover, measure and record the Northing, Easting, and Elevation values at the tips of the blade. Refer to Illustration 63 and Illustration 64 for the measurement location on the blade tips.
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      Illustration 65	g03614246

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      Illustration 66	g06369500
      CB460 display (1) LCD (2) Soft key labels (3) Soft keys (4) "Next key" (5) Zoom in (6) Zoom out (7) Escape key (8) Arrow keys (9) "OK" key (10) Light bar (11) Menu key (12) Power key (13) USB port

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      Illustration 67	g03614249
      "Text View 2"

   6. From the "Plan View" shown in Illustration 65, repeatedly press the "Next" key shown in Illustration 66 the "Text View 2" shown in Illustration 67 displays the Northing, Easting, and Elevation positions at the guidance point that has focus (Left tip), and the heading of the machine in degrees.

      Note: The coordinates shown on the display, reference where the cutting edge of the blade comes square with the tip of the blade. This point will be behind the corner tips of the blade. Refer to Illustration 63 and Illustration 64.

      Note: Blade tips may cut lower than the center of the blade. Variance from the projected cutting edge and the actual cut may be the result of the tip.

   7. Compare the recorded rover values with the values shown on the Cat Grade Control display.

   8. If the difference in the machine vs rover values for the Northing, Easting, and Elevation values at the left and right blade tips are not within the average error of 40mm on level ground, 80mm on slopes, for recommended action or repeat the measure-up procedure if necessary.

   9. Turn the machine approximately 135 degrees to the right or left and repeat Step 8d through Step 8h.

   10. If the values match to within 60.96 mm (0.200 ft) or desired accuracy, proceed with system operation. If the values do not match to within 60.96 mm (0.200 ft) or desired accuracy, repeat the measure-up procedure if necessary.

Installing a Customer Supplied Radio

The Cat Grade Control system for GNSS must use a radio that is compatible with the local GNSS base station radio. Local Trimble/Sitech dealer currently offers radios compatible with the Cat Grade Control system. These radios require Trimble infrastructure radios for compatibility. For sites that are not using radios with the Trimble infrastructure, customer supplied radios may be connected to the Cat Grade Control system. However, the customer supplied radio will need to be configured for use with the Cat Grade Control system.

This section outlines the wiring issues that must be addressed to provide communication with the Cat Grade Control system. Caterpillar makes no claim to compatibility with all radios. Additionally, Caterpillar assumes no responsibility for the performance of the system integrating customer supplied radios.

The following recommendations must be considered when installing a customer supplied radio:

• 18-gauge wire is recommended for all lines. Avoid narrower gauge wire.

• Machine pinouts may vary. Refer to the Schematic, UENR7739, "D8T Track-Type Tractor Electrical System" to determine correct pinouts.

• These instructions do not address any unique power requirements that may apply to individual customer supplied radios.

Power to a customer supplied radio is provided through the Cat Grade Control harness at a nominal 24 VDC (15 amp max). Power may vary from 22 - 28 VDC during radio operation. If regulated power is required by the customer supplied radio, it is the responsibility of the customer to provide a power converter to the radio. Additionally, it is the responsibility of the customer to wire the power converter to the radio.

Follow the procedure below to connect the third-party connector with the machine schematic:

1. Locate the schematic for the connector for the customer supplied radio. Refer to the owner's manual or the documentation from the manufacturer.

   1. Verify that 24 V DC nominal power is acceptable.

      Note: If there are any limitations on input power, find a suitable converter. The converter should be wired between the Cat Grade Control connection and the connection for the customer supplied radio.

   2. Find the required power and communications pins on the radio.

      These pins may vary for each customer supplied radio. The pins that are listed below are the minimum that are required:

      • + BAT

      • GRND

      • TX

      • RX

2. Locate the Electrical Schematic for the Cat Grade Control system for the specific Caterpillar machine. Schematics are available on SISWeb.

   1. Find the 8-pin connector for the GNSS radio.

   2. Trace back from the 8-pin connector to the 12- pin Deutsch connector. Note the pin number for the following connections:

      • + PWR

      • GRND

      • COM 2 TX

      • COM 2 RX
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   Illustration 68	g03614251

3. Wire the new cable.

   Use the information in Illustration 68 with the machine schematic to connect the cable.

Customer Supplied Radio Example

Field Conditions

The following are the different field conditions:

• Existing Cat Grade Control compatible GNSS base station

• Customer supplied radio at the GNSS base station required

• Create a cable that connects a compatible customer supplied radio to the Cat Grade Control system

The following checks should be made and verified before operating the system

1. Check whether the customer supplied radio is communicating CMR data over RS-232:

   Yes - The customer supplied radio is compatible with the Cat Grade Control system.

   No - The customer supplied radio is not compatible with Cat Grade Control system.

2. Check whether the machine radio can operate within 9-32 VDC:

   Note: Verify that all necessary connections can operate at machine voltages.

   For the radio to function properly with the system, the DTR line needs to be connected to V+ and be limited to 25V DC.

   Use a 240-2735 Wire As DC - DC power Converter to step the voltage down to 12 VDC.

3. Using the radio manufactures information, make all the necessary connections follows:

   • Power

   • Ground

   • TXD

   • RXD

   • DTR

   Note: DTR is required by this example radio to make the radio active.

4. Using the referenced pinouts for the machine harness, wire the following for the machine harness connector:

   • Power

   • Ground

   • COM2 TXD

   • COM2 RXD

5. Configure the machine radio and the Cat Grade Control system to communicate over "RS232".

   Reference: Reference Systems Operation, KENR5956, "Radio Utility".

   1. Change the settings in the "Customer Supplied Radio" field and "Display" field so that the settings match.

      Default Settings For The Display:

      Baud rate .....................38400

      Data Bits ................8 (Fixed setting on display

      Parity .......................................................None

      Stop Bits ................1 (Fixed setting on display)

6. Verify that the "over-the-air data/communications rate" are set the same in both the base and machine radio.

   Note: The optimal rate may vary depending on the radio. Typically the rate is between 4800 bps and 38400 bps. The same rate must be set in both the base radio and the machine radio. If the same rate is set, the operator may proceed. If the rates are not the same, use the radio configuration software to set both radios to the same over-their data/communications rate.

7. Connect the new adapter harness to the main harness and to the machine radio.

8. Apply power to the system and verify the communication to the base. Use the display to check the Left data link. The left data link should be increasing for the integrity. If not , refer to the Troubleshooting section.

Troubleshooting

No Power To Radio

To verify the power supply to the radio, perform the below checks:

• Verify connections to power and ground pins.

• Verify input power required for radio.

• If a converter has been added, ensure +PWR and Ground from Cat Grade Control connector are connected to the converter, and that +PWR and Ground from the converter are connected to radio.

No Communication Through Radio

To verify the radio communication, perform the below checks:

• Verify that the radio is a data terminal equipment (DTE) device.

Illustration 69	g03614253

• If the radio is a data communications equipment (DCE) device, modify the TX and the RX connections as shown in Illustration 69.

Note: It is critical to follow the documentation from the radio manufacturer to ensure that the proper handshake and/or other communications startup procedure is properly executed. Additionally, customer supplied radios may require additional pins to be grounded or to be tied to voltage, and these will also be identified in the documentation from the manufacturer.

Testing

Blade Pitch drift during the measure-up can cause some variance if the Blade Pitch position changes during the measure-up procedure.

Blade Pitch drift can be electronically monitored by watching the blade pitch cylinder extension values shown on the display.

Blade Pitch drift can be physically monitored by measuring the amount of cylinder rod chrome is exposed before and after the measure-up.

Pre-Delivery Measure-up Dimension Verification

To verify the machine dimensions, use either two known good points or use a GNSS survey tool to compare the points.

Follow the procedure below to perform the pre-delivery measure-up dimension verification:

1. Park the machine on a level surface that has a clear view of the sky.

2. To enter "Manager Mode", hold down the "OK" key as the display powers up.

3. Press the Next key until the second text window appears that shows Northing, Easting, and Elevation.

4. Verify which blade tip the system is using for the Grade Control display text items: "Blade: Left" or "Blade: Right".

5. Place the blade in the air and move the machine forward approximately 1 m (3.3 ft).

6. Lower the blade until the blade touches the ground or known survey point.

7. Note the values of the Northing, Easting, and Elevation from the display for the right and left tips of the blade.

8. Use the GNSS survey tool or the known survey point to measure the blade tip. Compare the values from the GNSS survey tool (or known point) and the values from the Grade Control display for the left and right tips of the blade. The elevation values should be within one tenth of a foot.

   Note: The display rounds off the values. The survey tool will carry out the values to more digits. If the values are not within one tenth of a foot, then the calibration and measure-up process will need to be repeated.

9. Repeat Step 3 through Step 8 to verify the right blade tip.

10. Park the machine on a side slope of greater than 10%.

11. Press the "Next" key from the main screen on the CB460 to view the text window showing the "Northing", "Easting", and "Elevation".

12. Verify which blade tip the system is using for the Grade Control display text items: "Blade: Left" or "Blade: Right".

13. Place the blade in the air and move the machine forward approximately 1 m (3.3 ft) on the side slope.

14. Lower the blade until the blade tip touches the ground or known point.

15. Note the values of the Northing, Easting, and Elevation from the Grade Control display for the right and left tips of the blade.

16. Use the GNSS survey tool or the known survey point to measure the blade tip. Compare the values from the GNSS survey tool (or known point) and the values from the Grade Control display for the left and right tips of the blade. The elevation values should be within one tenth of a foot.

17. Repeat Step 10 through Step 16 with the machine facing the opposite direction on the side slope so that if previously the machine sloped to the right, the machine would now slope to the left.

18. If the checks for both blade tips showed that the Grade Control values were higher than the values from GNSS survey tool or known point for one orientation of the machine on a side slope and showed that the Grade Control values were lower than the values from the GNSS survey tool or known point for the opposite orientation of the machine on the side slope, it is likely that a Body Sensor Adjustment will improve the accuracy of the system. See the "Chassis Inertial Measuring Unit (IMU) Yaw Alignment Compensation - Body Sensor Adjustment" section for more details.

Chassis Inertial Measuring Unit (IMU) Yaw Alignment Compensation - Body Sensor Adjustment

The Inertial Measuring Unit (IMU) is a component of the Cat Grade Control system on Track-Type Tractors and is critical to accurate machine guidance. An accurate GS420 Chassis IMU calibration is required for an accurate system and the IMU calibration must be completed prior to the machine measure-up.

The Chassis IMU calibration zeros the dual axis IMU sensor in the pitch and roll directions but assumes that the yaw direction of the sensor aligns with the yaw direction of the machine. The tolerance of the factory mounting of the IMU may include a small amount of sensor yaw from the chassis yaw.

A small misalignment of up to a few degrees will have no noticeable impact on level grading applications but when the machine is operating under side slope conditions, the yaw misalignment of the sensor may lead to a vertical error seen at the blade tips. A machine with an uncompensated IMU sensor will also exhibit blade slope error when operating under machine mainfall conditions.

Once the IMU calibration and measure-up is completed, the machine can be checked for accuracy as described in the "Pre-Delivery Measure-up Dimension Verification" section. If there is an accuracy problem on side slope conditions but not under level side slope conditions, there is the potential that the machine IMU could be slightly misaligned with the machine chassis.

The best way to determine whether a Chassis IMU Yaw Adjustment is necessary to measure the vertical error at the blade tips while the machine is on a side slope then turn around the machine 180 degrees and measure the vertical error at the blade tips again. If the vertical error direction and magnitude is consistent with the machine facing the opposite direction, the error is more likely to be associated with the Machine Measurements than the Yaw Adjustment. If the vertical error magnitude and direction is similar, the vertical error is likely to be associated with the GS420 Chassis IMU yaw. The severity of the slope that will show that a yaw misalignment error at the blade tip depends on the severity of the sensor skew.

The Cat Grade Control system on the track-type tractor is equipped with a process to compensate for slight IMU misalignment but it can only be performed after calibrating the IMU and measuring up the system.

Note: It is important that the Chassis IMU Calibration and Measure-Up process have been completed prior to adjusting the IMU.

If a vertical error is seen at the blade tips under side slope conditions and blade slope error is seen under mainfall conditions and not in level surface conditions, the following process can be completed to allow the system to compensate for any mounting differences in the IMU and improve the accuracy of the system.

Follow the procedure below to check and correct the vertical error when turning the machine:

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Illustration 70	g06107543
Side slope increasing to machine left

1. Set up the machine on a side slope where vertical error is seen on the blade tips.

2. Grade a side slope pass on the slide slope where the machine slope increased to the left of the machine.
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   Illustration 71	g06107565
   Side slope Increasing to machine right (Machine turned around)

3. After completing the pass, turn around the machine over the previous pass so that the machine is facing in the opposite direction.
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   Illustration 72	g06069486
   IMU Yaw Adjustment Screen

4. Check the vertical error that is seen at the blade tips. The side slope now should be increasing to the right of the machine.

   1. If the blade tips are low, adjust the slider to a larger number.

   2. If the blade tips are high, adjust the slider to a smaller number.

      Note: The IMU Adjustment Screen (Body Sensor Adjustment) can be accessed by navigating the following path: "Menu" >"Configuration" >"Body Sensor Adjustment"

5. Check the system by repeating Step 1 through Step 4 until the vertical error when turning around the machine is negligible.

Function Checkout

Follow the procedure below to checkout the system components:

1. Press the arrow keys until "Diagnostics" is highlighted

   Note: "Diagnostics" is always the last item in the list.

2. Press the "OK" key.

   A screen appears showing all the devices that are detected.

3. Verify that all the following components are found and configured:

   • CB460

   • Cat ECM

   • Radio

   • Two cab-mounted GNSS Antennas

4. Create a level plan or select a design by accessing the "Setup Menu" > "Configuration Menu" > "Select Design". Refer to the Operation and Maintenance Manual, M0098339 , "Cat^® Grade Control for the D8T Track-Type Tractors 3D".

5. If the machine checkout is "OK", then proceed to "Save Machine Settings" .

Save Machine Settings File

Follow the procedure below to save the machine settings file:

Note: This file should be stored in a safe place to help in the recovery of machine settings in the event of changing the display.

1. Enter service mode, by holding down the "OK" key as the display powers up.

2. Press "Setup Menu" to enter "Setup Menu - Configuration".

3. Select "Save Settings". Press the "OK" key.

4. Use the arrow key to select "Machine Settings". Press the "OK" key.

5. Use the arrow key to name file, with the serial number of the machine. Press the "OK" key.

6. Insert USB jump drive. The menu will change. Press F1 to select file destination "To USB" . Remove USB after file transfer is complete.

7. Press and hold the power key to power down the display.

Save Implement ECM Replacement File

Follow the procedure below to save the implement ECM replacement file:

1. Connect Cat ET to the machine and select the Implement ECM.
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   Illustration 73	g03797677

2. Click the "Service" tab, "Copy Configuration" selection, and select the "ECM Replacement" option. Refer to Illustration 73.

   Note: The measure-up dimensions of the machine are stored in the Implement ECM. If the ECM is replaced during machine service, measure and calibrate the machine again if the Implement ECM configuration data is not downloaded and saved.

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   Illustration 74	g03797678

3. Click the "Yes" button to acknowledge that the data must be loaded from the ECM.

4. Acknowledge the Implement ECM data was loaded.

5. Select "Save to File" and name/store appropriately.