320C, 322C and 325C Excavators Tool Control System System 1: Solenoid Valve (Proportional Reducing) - Calibrate - Negative Flow Control Caterpillar

This calibration procedure is used in order to record the correction data of the proportional solenoid valve for the tool control. This calibration should be done at the following times: replacement of the NFC solenoid valve, replacement of the ECM, flash new software and adjustments to the horsepower controls on the pump.

Before this procedure is performed , ensure that the following requirements are met:

• Verify that the governor actuator is properly calibrated. If necessary, see Testing and Adjusting, "Governor Actuator - Calibrate" for the Tool Control System.

• Verify that the pilot pressure is set to the proper specification that is found in Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust" for the machine.

• Verify that the main relief valve is set to the proper specification that is found in Testing and Adjusting, "Relief Valve (Main) - Test and Adjust" for the machine.

• Verify that the proportional reducing valve (power shift) is properly calibrated. If necessary, see Testing and Adjusting, "Proportional Reducing Valve - Calibrate (Power Shift)" for the Engine and Pump Control System.

There are two methods for calibrating the proportional solenoid valve for negative flow control. One method uses a flow meter and a pressure gauge. This method is more accurate. The other method uses only a pressure gauge. This method is less accurate. Both methods are described below.

Note: The less accurate method which uses only a pressure gauge is used only when a flow meter is not available.

The device for activation for the work tool is the right foot pedal.

Illustration 1	g00988798

Calibration With a Pressure Gauge and a Flow Meter

Note: When additional safety is needed on machines that are equipped with a swing brake solenoid, disconnect the swing brake solenoid so that the swing brake remains engaged.

1. Position the machine on level ground and stop the engine.

2. Release the pressure in the hydraulic system. Refer to Testing and Adjusting, "Hydraulic System Pressure - Release" for the machine.

3. Install a 400 L (106 US gal) flow meter in the hydraulic line to the tool.

   Note: Table 1 lists the parts which appear in 2.

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   Table 1

   TOOL CHART FOR FLOW TEST
   Item Number	Part Number	Part Description		Quantity
   10	4C-9910	Flow Meter		1
   11	6K-6307	O-ring seal		2
   12	8C-9026	Adapter		2
   13	7M-8485	O-ring seal		8
   14	4C-6482	Nipple		4
   	9U-5086	Optional Dust Cap		4
   15	4C-6481	Coupler		4
   	9U-5084	Optional Dust Plug		4
   16	4C-8767	Coupling		4
   17	5P-1010	Sleeve		4
   18	5P-0201	XT-5 Hose 3.5 m (12 ft)		2
   19	8T-4194	Bolt		4
   20	8T-4223	Hard Washer		2
   21	1P-5767	Half Flange		4
   22	1U-8293	Adapter		2
   23	1P-3704	Rectangular Seal		2
   28	6V-4143	Coupler		2
   29	6V-3014	Hose		1
   30	6V-3989	Nipple		1
   31	8T-0861	Pressure Gauge		1

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   Illustration 2	g00990081
   (24) Port on supply line for work tool (25) Port on return line for work tool (26) Pump pressure tap (27) Pump pressure tap (35) Main pump

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   Illustration 3	g00990153
   (10) Flow meter (32) Supply line for work tool (33) Return line for work tool (34) Load valve for flow meter

   1. Connect one end of hydraulic line (32) for the flow meter to the connection on the left side of the flow meter (input port). Connect the other end of this hydraulic line to the port on the supply side of the stick.

   2. Connect one end of the second hydraulic line (33) for the flow meter to the connection on the top of the flow meter (output port). Connect the other end of this hydraulic line to the port on the return side of the stick.

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Illustration 4	g01000946
Pump compartment for the 320C and the 322C (26) Pressure tap (idler pump) (27) Pressure tap (drive pump) (37) Pressure tap (power shift)

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Illustration 5	g01000947
Pump compartment for the 325C (26) Pressure tap (idler pump) (27) Pressure tap (drive pump) (37) Pressure tap (power shift)

4. Install a 40000 kPa (5800 psi) pressure gauge on pressure tap (26) .

   Note: Refer to Illustration 4 for the 320C and the 322C machines.

   Note: Refer to Illustration 5 for the 325C machines.

5. Place the backup switch in the AUTO position.

6. Start the engine.

7. Move the engine speed dial to position 10.

8. Increase the oil temperature to 50 °C (122 °F).

9. Be sure that the tool that is selected for use is a work tool that provides one pump flow. The default programming for "TOOL#2" is for one pump operation. Refer to Testing and Adjusting, "Work Tool - Select" for the Tool Control System. If "TOOL#2" has been reprogrammed for two pump flow, select a tool that provides one pump flow.

10. Enter the service mode on the monitor. See Testing and Adjusting, "Service Mode - Enter" for the Tool Control System for step-by-step instructions on entering the service mode.

Illustration 6	g00935640
Monitor Panel (1) Up key (2) Down key (3) Left key (4) Right key (5) Set key (6) Menu key (7) Cancel key (8) OK key

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Illustration 7	g01000769

1. After entering service mode, the above screen should be displayed.

   Note: The fourth line will indicate the sales model of the excavator.

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Illustration 8	g00694795

2. Press down key (2) in order to highlight line 2. Select "CALIBRATION" with left key (3) or right key (4) . This is shown in illustration 8.

3. Press down key (2) in order to highlight line 3. The calibration device name will appear on line 3. Press the keys for direction in order to scroll through the calibrations that are available. Change the calibration device name to "1PFLOW". The calibration must be performed at the higher flow rate ("1PFLOW - MAX"), and the calibration must be performed at the lower flow rate ("1PFLOW - MIN"). Refer to Table 2 for the proper flow rate of the machine that is being tested.
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   Table 2

   Flow Rates Flow rates at 16000 ± 500 kPa (2320 ± 72 psi)
   	One Pump MAX	One Pump MIN	Two Pump MAX	Two Pump MIN
   320C and 322C	180 ± 3 L (48 ± 0.8 US gal)	120 ± 3 L (32 ± 0.8 US gal)	NA	NA
   325C	200 ± 3 L (53 ± 0.8 US gal)	140 ± 3 L (37 ± 0.8 US gal)	NA	NA

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Illustration 9	g00947067

4. Perform the "1PFLOW - MAX" calibration first. In order to change from the "MIN" calibration to the "MAX" calibration, highlight line 3. Press menu key (6) in order to move the portion of line 3 that is highlighted to the right. This is shown in illustration 9. Press left key (3) or right key (4) in order to change the calibration from "MIN" to "MAX".

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Illustration 10	g00947069

5. Press down key (2) in order to highlight "STANDBY" on line 4.

6. Press OK key (8) . The calibration value is now highlighted on line 4. The machine ECM increases the engine speed to "10".

7. Press the device for activation 3 times and release the device for activation 3 times.

8. Press and hold the device for activation.

9. Adjust the setting of the load valve on the flow meter (34) and observe pressure gauge (14) . Adjust the setting until the pressure gauge indicates 16000 ± 250 kPa (2320 ± 36 psi).

   Pump pressure is affected by the flow and the open rate of the load valve on the flow meter (34) . The load valve on the flow meter (34) must be adjusted when a change of calibration is made. When you adjust the calibration value and the open rate of the load valve on the flow meter (34) setting, always return the tool to the neutral position and repeat the calibration.

10. Refer to Table 2 and observe the flow meter in order to verify that the flow rate is within the proper specifications.

11. If the flow is not within the proper specifications, the machine must be adjusted. Proceed to steps 12 through 18.

12. Release the right foot pedal. DO NOT change the setting of the load valve on the flow meter (34) .

13. Adjust the value on line 4 of the monitor. Press left key (3) or right key (4) in order to adjust the value on line 4.

    It is possible to correct the flow control pressure from "+60" to "-60" by using the monitor.

    The flow changes approximately 2 L/min (0.5 US gpm) when the left key (3) or the right key (4) is pressed one time.

14. Press and hold the device for activation.

15. If the pressure is out of the proper range, adjust the load valve on the flow meter (34) until the pressure gauge indicates 16000 kPa (2320 psi).

16. Refer to Table 2 and observe the flow meter in order to verify that the flow rate is within the proper specifications.

17. Repeat steps 12 through 16 until the flow rate in step 16 is obtained with no adjustments of the monitor or the load valve for several repetitions.

    Note: Press and hold the device for activation for a few seconds in order to allow the hydraulic system to stabilize before repeating the steps.

18. When the reading is within the proper range, continue to hold the device for activation and press set key (5) in order to save the value. Line 3 will automatically be highlighted. The "1PFLOW - MIN" calibration will now be performed.

    Note: If set key (5) is not pressed the calibration will not be saved.

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Illustration 11	g00947071

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Illustration 12	g00947072

19. Change the flow that is being calibrated from the "MAX" calibration to the "MIN" calibration. Highlight line 3 and use menu key (6) in order to move the portion of line 3 that is highlighted to the right. This is shown in illustration 12. Press left key (3) or right key (4) in order to change the calibration from "MAX" to "MIN".

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Illustration 13	g00981198

20. Press down key (2) in order to highlight "STANDBY" on line 4.

21. Press OK key (8) . The calibration value is now highlighted on line 4. The machine ECM increases the engine speed to "10".

22. Press the device for activation 3 times and release the device for activation 3 times.

23. Press and hold the device for activation.

24. Adjust the setting of the load valve on the flow meter (34) and observe pressure gauge (14) . Adjust the setting until the pressure gauge indicates 16000 kPa (2320 psi).

    Pump pressure is affected by the flow and the open rate of the load valve on the flow meter (34) . The load valve on the flow meter (34) must be adjusted when a change of calibration is made. When you adjust the calibration value and the open rate of the load valve on the flow meter (34) setting, always return the tool to the neutral position and repeat the calibration.

25. Refer to Table 2 and observe the flow meter in order to verify that the flow rate is within the proper specifications.

26. If the flow is not within the proper specifications, the machine must be adjusted. Proceed to steps 27 through 34.

27. Release the right foot pedal. DO NOT change the setting of the load valve on the flow meter (34) .

28. Adjust the value on line 4 of the monitor. Press left key (3) or right key (4) in order to adjust the value on line 4.

    It is possible to correct the flow control pressure from "+60" to "-60" by using the monitor.

    The flow changes approximately 2 L/min (0.5 US gpm) when the left key (3) or the right key (4) is pressed one time.

29. Press and hold the device for activation.

30. Refer to Table 2 and observe the flow meter in order to verify that the flow rate is within the proper specifications.

31. If the pressure is out of the proper range, adjust the load valve on the flow meter (34) until the pressure gauge indicates 16000 kPa (2320 psi).

32. Refer to Table 2 and observe the flow meter in order to verify that the flow rate is within the proper specifications.

33. Repeat steps 27 through 32 until the flow rate in step 32 is obtained with no adjustments of the monitor or the load valve for several repetitions.

    Note: Press and hold the device for activation for a few seconds in order to allow the hydraulic system to stabilize before repeating the steps.

34. When the reading is within the proper range, continue to hold the device for activation and press set key (5) in order to save the value. Line 3 will automatically be highlighted.

    Note: If set key (5) is not pressed the calibration will not be saved.

    The "1PFLOW" calibration is now complete. It is possible for an error to occur when you are calibrating. The text of the error will appear on line 4.

Illustration 14	g00981200

If an error is detected, the code number of the error will be shown on line 4. The following table lists the possible error codes and corrective actions.

Calibration With a Pressure Gauge

Note: There are two methods for calibrating the proportional solenoid valve for negative flow control. One method, which uses a flow meter and a pressure gauge, is more accurate. The method that is listed below uses only a pressure gauge. This method for calibrating the proportional solenoid valve is less accurate. This method should be used only when a flow meter is not available.

Note: When additional safety is needed on machines that are equipped with a swing brake solenoid, disconnect the swing brake solenoid so that the swing brake remains engaged.

1. Position the machine on level ground and stop the engine.

2. Release the pressure in the hydraulic system. Refer to Testing and Adjusting, "Hydraulic System Pressure - Release" for the machine.

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Illustration 15	g00970333
(38) Pressure tap for the proportional solenoid valve for negative flow control

3. Attach a 4900 kPa (750 psi) pressure gauge to the pressure tap for the proportional solenoid valve for negative flow control (38) .

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Illustration 16	g00796964
The Backup Switch

4. Place the backup switch in the AUTO position.

5. Start the engine.

6. Move the engine speed dial to position 10.

7. Raise the oil temperature to 50° ± 5°C (122° F).

8. Verify that the pilot pressure is set to the specifications that are in Testing and Adjusting, "Relief Valve (Pilot) - Test and Adjust" for the machine.

9. Enter the service mode on the monitor. See Troubleshooting, "Using Service Mode" for the Tool Control System for step-by-step instructions on entering the service mode.

10. Ensure that a "TOOL#" is selected.

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Illustration 17	g01000769

11. After entering service mode, the above screen should be displayed.

    Note: The fourth line will indicate the sales model of the excavator.

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Illustration 18	g00694795

12. Press down key (2) in order to move the cursor to line 2. "ECM SUMMARY" will be highlighted. Use right key (4) in order to scroll to the right. Select "CALIBRATION".

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Illustration 19	g00694723

13. Press down key (2) in order to highlight line 3. On line 3, the calibration device name will be indicated. Press the keys for direction in order to scroll through the calibrations that are available. Change the calibration device name to "NFC PRV".

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Illustration 20	g00694765

14. Press menu key (6) in order to move the cursor to the right. Use left key (3) or right key (4 ) in order to change from the "LOW " pressure or the "HIGH" pressure.

    Note: Perform the "LOW" pressure calibration first.

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Illustration 21	g00694694

15. Press down key (2) in order to move the cursor to line 4 and highlight "STANDBY".

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Illustration 22	g00694710
Line 4 may show any number.

16. Press OK key (8) . This will automatically set the engine speed to high idle. This will also change the display from "STANDBY" to a number.

17. With the engine speed at high idle, move the joystick for the stick until the stick is at full "STICK IN" position (full extension of the stick cylinder). Hold the joystick for the stick in this position.

18. Press the device for activation 3 times and release the device for activation 3 times.

19. Press and hold the device for activation.

20. Record the "LOW" pressure reading at pressure tap (38) for the proportional solenoid valve for negative flow control. The pressure specification for the negative control is 1500 ± 50 kPa (220 ± 7 psi). Press left key (3) or press right key (4) in order to change the number on line 4 of the display screen. This action changes the pressure reading on the gauge. In order to lower the pressure, press left key (3) . In order to raise the pressure, press right key (4) .

21. Repeat steps 18 through 20 until the flow rate in step 20 is obtained with no adjustments of the monitor or the load valve for several repetitions.

    Note: Press and hold the device for activation for a few seconds in order to allow the hydraulic system to stabilize before repeating the steps.

22. When the pressure is within the pressure specification, continue to hold the device for activation and press set key (5) in order to memorize the pressure setting. The cursor moves to line 3 after the setting is memorized.

    Note: If set key (5) is not pressed the calibration will not be saved.

23. Move the joystick for the stick to the NEUTRAL position.

24. Release the device for activation.

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Illustration 23	g00694723

25. Press up key (1) in order to highlight "NFC1 PRV".

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Illustration 24	g00694765

26. Press menu key (6) in order to highlight "LOW".

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Illustration 25	g00979849

27. Use right key (4) in order to scroll to the right. Change the text that is highlighted to "HIGH".

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Illustration 26	g00694694

28. Use down key (2) in order to highlight "STANDBY".

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Illustration 27	g00694710

29. When "STANDBY" is highlighted, press OK key (8) . This will automatically set the engine speed to high idle. This will also change the display from "STANDBY" to a numerical value.

30. Move the joystick for the stick until the stick is at full STICK IN position (full extension of the stick cylinder). Hold the joystick for the stick in this position.

31. Press the device for activation 3 times and release the device for activation 3 times.

32. Press and hold the device for activation.

33. Record the "HIGH" pressure reading at pressure tap (38) for the proportional solenoid valve for negative flow control. The pressure specification for the negative control is 3000 ± 50 kPa (435 ± 7 psi). Press left key (3) or press right key (4) in order to change the number on line 4 of the display screen. This action changes the pressure reading on the gauge. In order to lower the pressure, press left key (3) . In order to raise the pressure, press right key (4) .

34. Repeat steps 31 through 33 until the flow rate in step 33 is obtained with no adjustments of the monitor or the load valve for several repetitions.

    Note: Press and hold the device for activation for a few seconds in order to allow the hydraulic system to stabilize before repeating the steps.

35. When the pressure is within the pressure specification, continue to hold the device for activation and press set key (5) in order to memorize the pressure setting. The cursor moves to line 3 after the setting is memorized.

    Note: If set key (5) is not pressed the calibration will not be saved.

36. Move the joystick for the stick to the NEUTRAL position.

37. Release the device for activation.

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Illustration 28	g00694653

38. If an error message is indicated on line 4 of the monitor during calibration, refer to following table for information on the error code.