- Check the calibration weight of the present calibration.
- Check the carryback weight in the present calibration.
- Check the date of the last modification.
- Set the present weigh range.
- Check the present weigh range. Pressures are sampled over a portion of the lift arc in order to calculate a payload weight.
- Enter the present carryback weight value or modify the present carryback weight value.
- Enter the present calibration weight value or modify the present calibration weight value.
- Start a new calibration. This calibration completely replaces any previous calibrations.
- Enter the present bucket volume value or modify the present bucket volume value.
Access to the calibration information is gained through the VIMS/LPS menus.
The Check Calibration Information function allows the operator to check five pieces of information about the currently active calibration.
- The date and time of the last complete calibration was performed.
- The present calibration weight.
- The date and time of the last modification to the calibration weight.
- The present carryback weight.
- The date and time of the last modification to the carryback weight.
Performing a complete calibration also requires modifying the calibration values and the present carryback weight value. The values of the date/time clock stamp are reset with the same information.
The calibration information is shown as a scrollable list of items on the message center. The contents of the list are displayed one value at a time. The description of each item is shown on the first line. The present value is shown on the second line. Message center displays of calibration information are shown below.
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| Illustration 1 | g00511663 |
Press the ">" key.
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| Illustration 2 | g00511666 |
Press the ">" key.
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| Illustration 3 | g00511667 |
Press the ">" key.
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| Illustration 4 | g00511668 |
Press the ">" key.
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| Illustration 5 | g00511669 |
To view the first item again, press the ">" key.
Note: The format of the time/date information is listed here:
HH:MM - Hours:Minutes
MM:DD:YY - Month/Day/Year
Access to the check weigh range function is gained through the VIMS/LPS menus. The weighing range of the lift arc is adjustable. The operator can check the present weigh range setting. The operator can check the location of the lift arm relative to the present weigh range. All of the values are displayed as percentages in the range from 0 percent “bucket on the ground” to 100 percent “bucket at max lift”.
For example, the weighing range is currently set between 30 percent and 80 percent. The lift arm angle is currently at 65 percent. The message center shows the following information:
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| Illustration 6 | g00511670 |
The “LIFT POS” percentage on the second line is updated automatically as the lift arm is moved. Pressing the "OK" key will return the message center to the calibration sub-menu.
Access to the set weigh range function is gained through the VIMS/LPS menus. The weighing range of the lift arc is adjustable. If necessary, the operator can modify the present weigh range. The lift height is measured as a percentage in the range from 0 percent “bucket on the ground” to 100 percent “bucket at max lift”. The weigh range sub-menu gives the operator a choice of two options. The operator can choose to adjust the weigh range top or the operator can adjust the weigh range bottom:
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| Illustration 7 | g00511803 |
The operator presses the "0" key in order to adjust the top of the weigh range or the operator presses the "1" key in order to adjust the bottom of the weigh range. Press the "OK" in order to return to the calibration menu. After choosing to adjust the top of the weigh range, the following three alternating message screens are displayed:
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| Illustration 8 | g00511811 |
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| Illustration 9 | g00511812 |
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| Illustration 10 | g00511815 |
The “LIFT POS” percentage on the second line is updated automatically as the lift arm is moved. The weigh range bottom adjustment procedure is identical with one exception. The word “TOP” is replaced by the word “BTM” in the messages. Press the "F2" key in order to return to the weigh range menu without any changes. Press the "OK" key in order to accept the new top/bottom weigh range. The system determines if the value is acceptable. The new weighing range will be temporarily displayed as percentages:
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| Illustration 11 | g00511817 |
Three rules govern the modification of the weigh range:
- The top of the weigh range must fall between 50 and 80 percent.
- The bottom of the weigh range must fall between 30 percent and 60 percent.
- The difference between the weight range top and weight range bottom must be at least 20 percent.
The weigh range must conform to the rules or one of three error messages are temporarily displayed after pressing the "OK" key:
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| Illustration 12 | g00511818 |
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| Illustration 13 | g00511819 |
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| Illustration 14 | g00511820 |
To exit the weigh range sub-menu, the operator must set the range to a value that does not violate any of the three rules. The operator may cancel the mode with no changes by pressing "F2".
Few limitations are placed on setting the weigh range. The person that adjusts the range setting must understand the possible effects of an improper setup. The weighing range must be set to an area of smooth operation in order to be effective.
Setting the range too low - The system may cause excessive reweigh indications. The system weighing accuracy may be degraded. Material breakout and rapid reverse transmission shifting to forward transmission shifting may cause the problem.
Setting the range too high - Setting the weigh point at the maximum lift high causes excessive reweigh indication.
Setting a narrow range - A narrow range limits the number of pressure sensor samples. Limited sample readings reduce the accuracy of the system.
Carryback weight is a weight correction value that is subtracted from each subsequent bucket weight in order to account for material which is stuck in the bucket. Carryback material is weighed and the carryback is never placed into the truck. For example, if the load in the bucket was 30 tons and the carryback weight was currently set to two tons, the calculated bucket weight would be 28 tons.
Note: The carryback weight cannot cause the calculated bucket weight to be a negative value. If the carryback weight were set to 10 tons and a weight of 6 tons were weighed, the calculated bucket weight would be zero tons. The value cannot be minus four tons.
Access to the enter carryback weight function is gained through the VIMS/LPS menus. At the beginning of the enter carryback weight function, the operator is shown three alternating help messages that describe the function of the carryback weight value:
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| Illustration 15 | g00512107 |
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| Illustration 16 | g00512109 |
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| Illustration 17 | g00512110 |
The help messages display four times or the operator can stop the messages by pressing the "OK" key. A two line menu display appears after the help messages:
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| Illustration 18 | g00512111 |
Press the "0" key in order to proceed with the calibration. To exit the VIMS/LPS menu mode, press the "1" key. To return to the calibration menu, press the "OK" key. Proceeding with the change prompts the operator to enter a new carryback weight:
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| Illustration 19 | g00512112 |
The operator uses the standard LPS method for entering data to input the new carryback weight. The new carryback weight value is subtracted from all future calculations of the bucket weight.
Note: The value of the present carryback weight and the date/time of the last modification can be viewed on the message center. Refer to the System Operations, "Check the Calibration Information" section of this manual for details about viewing data.
The calibration weight is the weight of material in the bucket during the last calibration. The calibration weight is merely used as a multiplier. The load in the bucket during calibration relates mathematically to the calculated bucket weight and the displayed bucket weights. For example, increasing the present calibration weight by 10 percent increases all subsequent weight calculations by 10 percent and decreasing the present calibration weight by 10 percent decreases all subsequent weight calculations. The mathematical relationship makes fine tuning of the payload system possible. For example, the operator loads a truck with 110 tons of material “verified on a scale”. However, VIMS/LPS measures the truck weight as only 100 tons. This may be caused by an improper calibration. The measurement can be corrected by making the calibration weight 10 percent heavier. For example, the present calibration weight is 20 tons. Increase the calibration weight by 10 percent up to 22.0 tons. This will apply the desired correction.
Access to the enter calibration weight mode is entered through the VIMS/LPS menus. A two line menu is displayed after selection of enter calibration weight:
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| Illustration 20 | g00512113 |
Press the "0" key in order to proceed with the calibration. To exit the VIMS/LPS menu mode, press the "1" key. To return to the calibration menu, press the "OK" key. Proceeding with the change prompts the operator to enter a new cailbration weight:
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| Illustration 21 | g00512121 |
The operator uses the standard LPS method for entering data to input the new calibration weight. The new calibration weight value is used for all future calculations of thebucket weight.
Note: The value of the present calibration weight and the date/time of the last modification can be viewed on the message center. Refer to the System Operations, "Check the Calibration Information" section of this manual for details about viewing data.
VIMS/LPS requires calibration before accurate payload measurements can be made. Calibration involves lifting the empty bucket several times and lifting a calibration weight several times. Calibration instructions for the operator are displayed on the message center. The calibration can be broken into seven overall steps. The steps define seven pieces of information to VIMS/LPS:
- Define the lift range of the boom.
- Empty bucket “10 point lift”
- Empty bucket “continuous lift”.
- Enter the calibration weight.
- Loaded bucket “10 point lift”
- Loaded bucket “continuous lift”
- Velocity compensation “5 lifts”
Although the calibrated weight is not needed until Step 4 the calibrated weight should be readily available. Turning OFF the machine in the middle of the calibration routine cancels the calibration. The operator must start the calibration from the beginning, if the machine is shut OFF. The system will return to using the values from the previously completed calibration.
There is no need to have a known calibration weight while the initial calibration is performed. However, the calibration weight will need to be measured after the initial calibration is completed. The measured weight of the calibration weight will need to be entered through the “update calibration menu” or inaccurate payloads will result.
Press the "F1" key in order to bring up the payload menu. Use the ">" key to scroll forward through the menu items. Press the "5" key for the “CALIBRATE PAYLOAD” menu.
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| Illustration 22 | g00512539 |
Press the "5" key for the “START NEW CALIB”:
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| Illustration 23 | g00512541 |
Press the "0" key for the “START NEW CALB” sub-menu:
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| Illustration 24 | g00512542 |
- Defining the Lift Range of the Boom
The following position points will be defined in Step 1:
- Upper position of the boom during normal operation
- Lower position of the boom during normal operation
The position points are used to determine a smaller range. The smaller range is defined as the lift zone. The initial calibration actually starts at this point.
- The calibration should begin with an empty bucket. The operator is instructed to empty the bucket of all materials. Then press the "OK" key.
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Illustration 25 g00512543 - The VIMS/LPS needs to verify the 0 percent “bucket on the ground” and 100 percent “bucket at max lift” points. The operator is instructed to lift the arm to the highest point in order to obtain the information. Then press the "OK" key.
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Illustration 26 g00512544 - The operator is then instructed to lower the lift arm to the ground. Then press the "OK" key.
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Illustration 27 g00512545 - Empty Bucket “10 Point Lift”
During Step 2, the VIMS LPS collects data at 10 stationary empty bucket pressure position points that are required in order to calculate the empty bucket stationary calibration curve. The operator is asked to tilt the bucket back. The operator is then asked to slowly lift the bucket. The system will ask the operator to stop the bucket at ten different points. The procedure is listed here:
- The operator is instructed to tilt the bucket back fully:
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Illustration 28 g00512566 - Next, the operator is instructed to raise the bucket slowly:
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Illustration 29 g00512567 - The operator will be instructed to stop lifting:
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Illustration 30 g00512569 - Steps 2a through 2d will be repeated ten times at ten different lift heights.
- The operator is instructed to tilt the bucket back fully:
- Empty Bucket “Continuous Lift”
In Step 3, a collection of empty bucket pressure samples are taken over the full lift in order to calculate the empty bucket lifting calibration curve.
- The operator is instructed to lower the bucket fully to the ground:
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Illustration 31 g00512570 - The operator is then instructed to tilt the bucket back fully:
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Illustration 32 g00512566 - Next, the operator is instructed to lift the load. The operator is then instructed to pull back the lift lever fully until the “STOP LIFTING” message appears. The procedure is listed here:
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Illustration 33 g00512571 - Maintain engine RPM at high idle. Throttle lock may be used to set the speed. Lift the load smoothly. Pull back the lift lever fully:
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Illustration 34 g00512573 - Stop lifting when the “STOP LIFTING” message appears.
Note: Stop BEFORE the lift arm hits the physical stops.
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Illustration 35 g00512576 - Repeat Steps 3a through 3e until the following message is displayed:
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Illustration 36 g00512577 - The operator is instructed to lower the bucket fully to the ground:
- Enter the Value Of the Calibrated Weight.
In Step 4, the calibration weight is required to be in the bucket. The calibration weight may be fabricated from a concrete or a steel tube of the specified diameter for the given model and filled with concrete. The calibration weight must be weighed on a certified scale in order to determine the exact weight. Alternately, a load of dirt or rock of unknown weight may be used for the calibration.
- The operator is instructed to load the calibration weight. Then press the "[OK]" key.
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Table 1 Approximate Calibration Pipe Weights Model Diameter and Length Weight 992G “ 1.83 m Ø × 3.05 m (6 ft Ø × 10 ft) ”“ 18704 kg (41235 lb) 20.6 Ton”994
994D“ 1.83 Ø × 3.05 m (6 ft Ø × 16 ft) ”“ 28150 kg (62060 lb) 31 Ton”Show/hide table
Illustration 37 g00513089 Refer to the Approximate Calibration Weight Table for dimensions.
(A) Diameter. (B) LengthShow/hide table
Illustration 38 g00512687 Removing the calibration weight from the holder Show/hide table
Illustration 39 g00512688 Calibration weight in the bucket Show/hide table
Illustration 40 g00512578 - VIMS/LPS will ask the operator if the calibration weight is known or unknown.
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Illustration 41 g00512579 - When the value of the calibration weight is known the operator presses the "0" key. The operator uses the “Enter Calibration Weight” function in order to enter the known calibration weight value.
In this example, the operator enters the value 217. Then press the "OK" key.
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Illustration 42 g00512580 - If the calibration weight value is unknown the operator presses the "1" key. A value of 20 English tons is assumed as the calibration weight. The operator is instructed to weigh the calibration load after the calibration is complete. The “Enter Calibration Weight” function is then used in order to enter the correct value of the calibration weight. A series of messages are used to inform the operator. The messages are repeated four times. The operator can also stop the messages by pressing the "OK" key. The messages are listed here:
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Illustration 43 g00512582 Note: The VIMS/LPS calibration will be unaffected if an unknown calibration weight is used.
- The operator is instructed to load the calibration weight. Then press the "[OK]" key.
- Loaded Bucket “10 Point Lift ”
In Step 5, VIMS LPS will sample ten stationary pressure position points in order to calculate the loaded bucket calibration curve.
- The operator is asked to tilt the bucket back fully:
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Illustration 44 g00512566 - The operator is then instructed to slowly raise the bucket:
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Illustration 45 g00512567 - The system will instruct the operator to stop lifting:
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Illustration 46 g00512569 - Steps 5a through 5c will be repeated ten times.
- The operator is asked to tilt the bucket back fully:
- Loaded Bucket “Continuous Lift”
In Step 6, VIMS/LPS collects bucket pressures samples over the full lift in order to calculate the loaded bucket lifting calibration curve.
- The operator is instructed to lower the bucket fully to the ground:
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Illustration 47 g00512570 - The operator is then instructed to tilt the bucket back fully:
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Illustration 48 g00512566 - Next, the operator is instructed to lift the load. Then pull back the lift lever fully until the “STOP LIFTING” message appears. The load lift is repeated in order to ensure consistency. The process is listed here:
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Illustration 49 g00512606 - Maintain engine RPM at high idle. Lift the load smoothly. The operator is then instructed to pull back the lift lever fully.
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Illustration 50 g00512573 - Stop lifting when the “STOP LIFTING” message appears.
Note: Stop BEFORE the lift arm hits the physical stops.
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Illustration 51 g00512576 - Repeat Step 6a through Step 6e until the following message is displayed.
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Illustration 52 g00512577 - The operator is instructed to lower the bucket fully to the ground:
- Velocity Compensation “5 lifts”
In Step 7, the lifting velocity compensation calibration curve is calculated. The operator is instructed to perform five additional loaded lifts. The loaded lifts are performed at the following engine speeds: 1650 RPM, 1550 RPM, 1450 RPM, 1350 RPM and 1250 RPM. Again, throttle lock may be used to set the engine speed.
- The operator is instructed to lower the bucket fully to the ground:
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Illustration 53 g00512570 - Next, the operator is instructed to lift the load. The operator is then instructed to pull the lift lever fully until the “STOP LIFTING” message appears. In order to ensure consistency, the loaded lift is repeated. The process is listed here:
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Illustration 54 g00512608 - Maintain the engine RPM at the specified value. lift the load smoothly. The operator is then instructed to pull back the lift lever fully.
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Illustration 55 g00512609 - Stop lifting when the “STOP LIFTING” message appears.
Note: Stop BEFORE the lift arm hits the physical stops.
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Illustration 56 g00512576 - Repeat Step 7a through Step 7d until the following message is displayed.
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Illustration 57 g00512577 - Repeat Step 7. Using the five previously stated engine speeds.
The following message will be shown on the message center after completing the five loaded lifts.
- The operator is instructed to lower the bucket fully to the ground:
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| Illustration 58 | g00512610 |
The calibration is now complete. The previous calibration has been replaced. The carryback weight is set to zero. The date/time stamps under the “Check Calibration Info” function are all set to the present time. The VIMS/LPS calibration sub-menu is displayed on the message center.
Recalibration should not be required for 6 to 12 months.
Recalibration is required when one of the following events occurs:
- Replacement of the VIMS main module
- A position sensor is adjusted.
- A position sensor is replaced.
- A lift cylinder pressure sensor is replaced.
- Replacement of the bucket
- Replacement of the lift arms