Digital III Fueling Vehicle Control System

Transcription

1 SM April 2005 Aerospace Group Conveyance Systems Division Carter Brand Ground Fueling Equipment Applicable additional manuals: SM Setup & Calibration User s Manual Digital III Fueling Vehicle Control System Periodic Re-Certification Fueling Pressure and Flow Rate Control Model 64335

2 Table of Contents Page 1.0 Objectives System Descriptions Component Descriptions Navigating the Menu System Certification/Flow Control Characteristics Verification Process

3 1.0 Objectives The document is to be provided to the enduser of the Carter Digital III fueling control modules Model The purpose is to establish a procedure that the end-user can utilize for periodic re-certification of the digital fueling control system after the system is initially set-up, calibrated and configured for proper functioning in the duration of the certified period. In addition to periodic re-certification required by the authority, the flow system should also be subjected to the following checking process in case a fueling hose or nozzle type was replaced. If the equipment replaced is of similar dimensions in flow path as the discarded units, it is suggested that the flow system be checked for proper flow control characteristic using the procedure in this document rather than being subjected to full calibration process per Carter menu SM Also, when the equipment change is performed on one particular hose, the checking process should be applied to that particular hose only. Checks on the other hoses are optional. 2.0 System Descriptions Digital III Control System includes two Carter Digital II control systems P/N and an OEM PLC vehicle control module. The Digital II systems provide the primary and secondary fueling pressure and flow control functions while the PLC controls the other mechanical functions of the of the vehicle. The scope of this document is limited to the setup, calibration and configuration of the fueling pressure and flow control functions. 3.0 Component Descriptions The fueling pressure and flow control functions of the Digital III control module includes the following items: 3.1 Vehicle Mounted Equipment Qty Item 1. Digital II Control Module P/N Primary Control Valve... 1 Typically: Hydrant coupler for hydrant servicer or bypass valve for refueler 3. Secondary Control Valve... 1 Typically: Inline Valve 4.Vehicle mounted pressure transducer P/N Pulser... 1 While Carter does not provide the pulser, it is recommended the user selects the equivalent of a Veeder-Root 100->1 Pulse Generator P/N: along with its required mounting kit P/N: Test Stand Mounted Equipment Qty Item 6. Test Stand Pressure Transducer P/N Calibration Equipment Qty Item 7. Hand-Held Calibration unit P/N with cable to connect the Hand-Held unit and Control Module included... 2 The item 5 pulsar provides the flow rate information to the Digital II control system to compute the compensated pressure at the nozzle. To accomplish this, the control system compares flow rate to sensed pressure at the item 4 vehicle mounted pressure transducer and performs a calculation to determine the maximum flow rate allowable while remaining within the pressure range pre-determined by the user. To provide a flow rate signal to the digital system, a pulse transmitter must be installed to and driven by the flow meter. While the Pulser is not available from Carter, the use of a Veeder-Root 100->1 Pulse Generator" P/N: along with its required mounting kit P/N: or equivalent is recommended. Typical installation of the vehicle mounted equipment items 1 through 5 listed above are illustrated in the figures 1 and 2. Figure 1 applies to hydrant servicer and figure 2 applies to refueler. The item 6 test stand pressure transducer is required to be mounted on the test stand in the calibration process of the following procedure and can be removed from the 3

4 test stand for safe storage after the process. See figure 3 for test stand set-up. Both the two item 7 hand-held calibration units are required in the calibration process. One calibration unit must be connected to each control module (primary and secondary, item 1) in the calibration process although only one system can be calibrated at a time. When a particular system (primary or secondary) is being calibrated, the handheld calibration unit must be connected to the item 6 test stand pressure transducer mounted on the test stand. See figures 4 and 5. Image of the item 1 control module is shown in figure 6 to facilitate clarification of the indicator lights and displays on these items. See paragraphs 3.4. Figure 4 Connection among Control Module Hand-held Calibration Unit and Test Stand Mounted Pressure Transducer Figure 5 Hand Held Calibration unit 4

5 FLOW RATE GPM LPM M 3 /HR PRESSURE PSI BAR KPa SOLENOIDS A B SYSTEM MONITOR OVRRD MODIFY NORM DIGITAL PILOT II CONTROL MODULE Carter Ground Fueling Division 671 W. 17th Street Costa Mesa, CA Ph (949) Figure 6: Digital II Control Module 3.4 Digital II Control Module The following describes the functions of all the displays and indicator lights found on the Digital II control module Model Refer to figure FLOW RATE display will indicate the rate of flow of the product. 2. The indicator lights to the right of the FLOW RATE display will illuminate to indicate the unit of measure at which the flow rate is being displayed. 3. NOZZLE PRESURE will indicate the pressure that the product is being dispensed. 4. The indicator lights to the right of the NOZZLE PRESSURE display will illuminate to indicate the unit of measure that pressure is being displayed. 5. ACTIVE NOZZLE indicator lights 1-6 will illuminate to indicate the nozzle or nozzles that are being used or that are not currently stowed. 6. The NORMAL (Norm) indicator light will illuminate to indicate that the power to the control module is on and that the PRESURE OVERRIDE switch is not applied to select the alternate refueling pressure setting. 7. The OVERRIDE (Ovrrd) indicator light will illuminate to indicate that the pressure control system has been set to select the user alternate pressure setting. See item 12 below for more information. 8. The MODIFY indicator light will illuminate to indicate that the handheld unit is connected and is presently set to MODIFY mode. 9. The Solenoids A and B indicator lights will illuminate to indicate that an electric signal is being sent to the solenoids. In normal operation these lights will be flashing as the control 5

6 module affects the operation of the valve to control pressure. 10. The SYSTEM MONITOR indicator light is normally off. If this light should come on, it would indicate a problem with the fuel filter differential pressure. (Note: The filter differential pressure function is currently not used). 11. Not shown in this diagram is an amber indicator light on the top of the box at the upper right hand corner. This light will illuminate to indicate when the DEADMAN switch has been activated, and it will flash as required by the timer function, to indicate that a time-out condition is imminent. 12. Not shown in this diagram is the PRESSURE OVERRIDE switch, which is located on the bottom center of the box. When this button is pushed and held for a few seconds, the system will control at an alternate pressure, as previously set by the user during calibration and set up process. Note that the display of the Digital-II control module will sometimes display some unusual looking characters. This happens because this type of (numeric) display is designed to indicate numbers instead of letters. Review the following table that includes the display characters and the letters or numbers it is intended to indicate. 4.0 Navigating the Menu System In the calibration process, follow this procedure step by step to navigate through the menu which will be displayed on the LCD display panels of the control module until the calibration process is completed. See figure 7 for details of menu display on the control module as the control buttons on the hand-held calibration unit are applied. To navigate the menu tree system: The power to both the primary and secondary control modules must be off. When the power is off, both displays on the control modules will be blank, and all indicator lights will be off. Refer to Reset in section 1 for additional information. Connect the cable between the handheld unit and the control module. This applies to both primary and secondary systems. See figure 4. 6

7 Connect the test stand pressure transducer cable to the hand-held unit for the system to be calibrated only. See figure 4. WARNING Connecting the cable from the hand-held unit to the control module when the power is on can damage the hand-held unit and the control module. Apply power to the control module. Set the rotary switch on the hand-held unit to the MODIFY position. Review the menu system diagram. Pushing the LEFT arrow button on the held-held unit will always return the system to the main program menu. Pushing the RIGHT arrow button will display the next branch on the menu tree. The UP and DOWN arrow buttons are used to change the settings. On some occasions the DOWN button will be used to open a sub-menu within the menu tree. Use the LEFT, RIGHT, UP and DOWN buttons on the hand-held unit to scroll through the various functions of the control module as shown in figure 7 Follow the set-up, calibration and configuration procedure as detailed in paragraph 5 to input the required parameters into the control module. Upon completion on navigating through the menu system, turn the rotary switch on the held-held unit to the OPERATE position. Turn the power off to the control module. Disconnect the hand-held unit from the control module only in power off condition. Apply power to the control system only after the hand-held units are disconnected. As power is applied, the control module will power up in the OPERATE mode whenever the hand-held unit is not connected to it. 7

8 Figure 7: Calibration Menu Tree 8

9 Figure 8: Menu Display on Control Module 9

10 5.0 Certification/Flow Control Characteristics Verification Process The purpose of this certification process is to verify the flow control characteristics of the Carter Digital III fueling vehicle control system that has been subjected to the calibration process per Carter manual SM Test set-up It is required that the refueling equipment be set up to flow fuel through a test stand as shown in figure 3. The nozzle in the fueling vehicle intended to be certified or checked is to be removed from its interlock and connected to the flow test stand such that the corresponding nozzle indicator light must be illuminated on the control module. Only one of the two (primary or secondary) systems can be checked at one time. When Verification Process With the fueling vehicle in ready to fuel condition, the shut-off valve(s) downstream of the test stand receiver is to be placed in full open position. Apply the deadman to initiate fuel flow. Record the duration from applying the deadman to a stable full flow is observed. The opening time shall be within 5 to 10 seconds. a hose in the primary system is being checked, it is required that the secondary system be placed in full flow condition and vice versa. In the following steps paragraph 5.2 through 5.4, it was assumed that the primary system is being checked and the secondary system is placed in full flow condition unless otherwise specified. To place the secondary system in full open position, connect a hand-held calibration unit to the secondary system. Place the secondary system and have it remain in the PLSR CAL 1 sub-menu by following the steps shown in figure 7. This will put the secondary system in full flow condition as deadman is applied. 5.2 Opening time verification Trouble Shooting See below: If the opening time is lower than 5 seconds, re-adjust by utilization the OT sub-menu per Carter calibration manual SM If the opening time exceeds 10 seconds, re-adjust by utilization the OT sub-menu per Carter calibration manual SM If the re-adjustment fails to speed up the opening time, there might be trapped air in the command hose. The trapped air must be bled from both ends of the command hose; that is, at the coupler and the command hose wheel fitting as the deadman is applied. If upon application of the deadman, flow started and then shut abruptly, there might be air pockets trapped in certain pipe sections in the fueling vehicle. The situation might be corrected by flowing through all hoses, individually or simultaneously, to remove all air pockets in the system before the checkup process can re-start per this paragraph 5.2. Upon verification of acceptable opening time, proceed to nozzle flow limit check. 5.3 Nozzle Flow Limit Verification Verification Process While deadman is applied and full flow is established, check the actual flow rate against the maximum flow rate limit programmed into the FL nozzle flow limit sub-menu under the Set-Up menu. The actual full flow rate should never exceed the FL value entered into the control module for the particle hose in check. Trouble Shooting If the actual flow rate exceeds the programmed maximum flow limit for the nozzle in test, the pulser might be out of calibration. The control module circuit board or the pulser might be defective. The defective equipment must be replaced and re-calibrated. Calibration of the flow system per manual SM must be repeated before the fueling vehicle can be placed in service. If the actual full flow rate is excessively low, depending on the design of the fueling vehicle, the control module circuit board or the pulser might be defective and require replacement and re-calibration. The controlled elements such as the inline valve, bypass valve, hydrant coupler or solenoid manifold might be defective or require overhaul. 10

11 Upon verification of nozzle flow limit on the hose in test, proceed to nozzle control pressure check. 5.4 Nozzle Control Pressure Verification Verification Process While deadman is applied and full flow is established, slowly reduce flow rate by closing the throttle valve downstream of the test stand nozzle adapter. The flow rate shall be throttled down by 50 gpm increments until flow rate is no lower than 50 gpm. At every flow rate increment, wait for 5 to 10 seconds until flow stabilized. Check the actual pressure at the nozzle receiver against the nozzle control pressure setting programmed into the PSET submenu under the Calibration menu. The actual back pressure observed at the test stand reference gauge should not exceed the set value for more than one second at a time after the flow is stabilized. The displayed nozzle pressure value on the control module should conform to the test stand reference pressure gauge without +2 psi. Trouble Shooting If the actual nozzle pressure deviates excessively from the displayed nozzle pressure on the control module, the calibration on the nozzle control pressure setting might be off due to change of equipment or system conditions. The vehicle mounted pressure transducer might be defective and must be replaced. Re-calibration on the Digital III system per Carter manual SM is required. Upon verification of nozzle control pressure setting on the hose in test, proceed to pressure surge protection verification. 5.5 Pressure Surge Protection Verification Verification Process Apply deadman and open the throttle valve downstream of the test stand nozzle receiver such that full flow is re-established. Actuate the surge valve, downstream of the test stand nozzle receiver, to close position. Closing time of this surge valve shall be within 1 to 2 seconds. Observe the surge pressure created by the rapid flow shut-off. Maximum pressure surge recorded at the test stand shall not exceed 120 psig. Repeat this test by throttling the nozzle back pressure at 40 to 50 psig before the surge valve is actuated closed. Again, maximum pressure surge recorded at the test stand shall not exceed 120 psig. Trouble Shooting If the control valves (Inline valve, bypass valve or hydrant coupler), fail to suppress pressure surge to below 120 psig, these control valves must be checked for any mechanical defect. The solenoids controlling these valves might be jammed or nonfunctional. The fittings connecting the inlet and outlet port for the solenoid manifolds might be blocked by debris. The pre-charge setting on the surge suppressors on the fueling vehicle might be too high or too low. The vehicle mounted pressure transducer might be defective and require replacement. When these mechanical defects (with the exception of the defective pressure transducer) are repaired and the equipment is re-installed in the fueling vehicle, they should be subjected to the certification process as detailed in this document. Re-calibration of the digital control systems might not be necessary as these equipment changes should not affect the pressure drop characteristics of the fueling vehicle. If the vehicle mounted pressure transducer is identified as defective and replaced, the fueling system must be re-calibrated per manual SM without exception. Upon successful demonstration of surge suppression, proceed to closing time verification. 11

12 5.6 Closing Time Verification Verification Process Apply deadman and open the valves downstream of the test stand nozzle receiver such that full flow is re-established. Then release the deadman to stop fuel flow. Record the closing time from release of the deadman to full flow stop. Also record the amount of fuel overshoot through the fueling vehicle during this closing period. The closing time shall be within 2 to 5 seconds and the fuel overshoot shall not exceed 5% of the flow rate (per minute) at the time the deadman is released. Trouble Shooting If the closing time exceeds the 2 to 5 seconds, re-adjust by utilizing the CT sub-menu per Carter calibration manual SM If the re-adjustment fails to speed up the opening time, the solenoids that control the control valves might be defective and must be replaced. If the fuel overshoot exceeds the 5% value, further lower the closing time by utilizing the CT sub-menu per Carter calibration manual SM Normally, if the closing time is close to the 2 seconds lower limit, the system should have not a problem complying to the 5% overshoot requirement. Upon completion of all the verification processes per paragraphs 5.1 to 5.6, the functional verification on the specific hose (identified by the eliminated indicator light) in the specific system (such as primary) is completed. 5.7 Complete verification process on one specific system (primary or secondary) Paragraphs 5.1 to 5.6 above details process required to certify one specific hose (identified by the nozzle indicator light on the control module) in one specific system (such as the primary or secondary system). To complete the certification on this specific system, the hose(s) tested must be returned to its stowage interlock and all the other hoses or hose combinations allowed by the OEM PLC must be subjected to the same verification steps (paragraphs 5.1 to 5.6) one at a time. 5.8 System flow limits verification After the performance of all hoses in the specific system tested are verified, hoses in group might be connected to the test stand and flow is to be established per paragraph 5.3. It will be observed that the full flow rate shall never exceed the maximum system flow rate limit programmed into the SFL system flow limit sub-menu under the Set-Up menu for the system in test. 5.9 Complete verification process on multiple systems (primary and secondary) For fueling vehicle consisting of both the primary and secondary digital flow control systems, the test steps per paragraphs 5.1 to 5.8 applies to only one of the systems (such as the primary). The same verification and checkup steps must be performed on the secondary system also while the primary system is kept in full flow condition Normal fueling operation certification Upon completion of all performance checks on all hoses and both primary and secondary systems, disconnect the handheld calibration units from the control modules (primary and secondary). Selected hose(s) is to be connected to the test stand and subjected to fueling test simulating a typical fueling operating to an aircraft. The fueling characteristics shall conform to the parameters required of the primary system at all phases of the fueling operations. After successful demonstration of this normal fueling simulation, stop all fuel flow and secure all fueling equipment to the corresponding stowage or interlocks. Certification of the fueling vehicle is complete. 12

13 Aerospace Group Conveyance Systems Division 9650 Jeronimo Rd. Irvine, CA USA Ph: (949) Fax: (949)