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Varian 948 Operation And Service Manual

Leak detectors
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Models
947, 948 and 960
Leak Detectors
Part No. 699909947
Revision H
March 2003
vacuum technologies
OPERATION AND
SERVICE MANUAL

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Summary of Contents for Varian 948

  • Page 1 Models OPERATION AND SERVICE MANUAL 947, 948 and 960 Leak Detectors Part No. 699909947 Revision H March 2003...
  • Page 2 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Models 947, 948 and 960 Leak Detectors Contra-Flow, MacroTorr, TriScroll and ConvecTorr are trademarks or registered trademarks of Varian Vacuum Technologies. Apiezon is a registered trademark of M&I Materials Ltd.

  • Page 3: Table Of Contents

    Pumps ...........................xxi Varian Services ......................... xxii Contacting Varian Vacuum Technologies ................. xxii Section 1. Introduction to Models 947, 948 and 960 Leak Detectors ..........1-1 1.1 Platform Electronics ......................1-4 1.2 Unpacking the 947/948/960 ....................1-4 1.2.1 Unpacking Instructions....................1-4 1.2.2 Removing the 947/948/960 from the Skid..............
  • Page 4 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Section 2. Leak Detector Integration ....................2-1 2.1 Physical Considerations ...................... 2-1 2.2 Common Configuration ......................2-1 2.3 Electronic Considerations for the Optional Rear Panel Interface......... 2-6 2.3.1 Discrete I/O J120 Inputs ..................... 2-6 2.3.2 BCD J121 Outputs ......................
  • Page 5 Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.4.1 Removal of the Spectrometer Tube and Preamplifier ........4-12 4.2.4.2 Disassembly of the Spectrometer Tube and Preamplifier ......4-14 4.2.4.3 Spectrometer Tube Cleaning ............... 4-16 4.2.4.4 Reassembly of the Spectrometer Tube and Preamplifier ......4-16 4.2.4.5 Reinstallation of the Spectrometer Tube ............
  • Page 6 Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.1.2 Removing the Top Panel ...................B-3 B.1.3 Replacing all Panels and Covers ................B-4 B.1.3.1 Replacing the Service Pendant Shelf .............B-4 B.1.3.2 Replacing the Top Panel ................B-5 B.2 Replacing the Ion Source ....................B-6 B.3 Replacing the Turbo Pump....................B-9...
  • Page 7 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Appendix C. Communications Protocol ..................C-1 C.1 Protocol (RS-232)....................... C-1 Appendix D. Inputs and Outputs ....................D-1 D.1 Service Serial Interface (J1) ....................D-1 D.2 Optional Rear Panel Interface .................... D-1 D.2.1 Discrete I/O Parallel Interface (J120) ...............
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  • Page 9 Models 947, 948 and 960 Leak Detectors Operations and Service Manual List of Figures Figure Description Page 947 Leak Detector....................... 1-2 948/960 Leak Detector......................1-3 Front Panel Controls and Indicators ................... 1-6 Turret Door Instruction Label ....................1-8 Rear Power Panel....................... 1-9 Service Pendant........................
  • Page 10 Models 947, 948 and 960 Leak Detectors Operations and Service Manual The Turbo Power Connection ...................B-11 Radiator Clamp holding Fan to Turbo................B-11 B-10 Location of Forepump and Rough Pump — Wet and Dry Configurations ......B-15 B-11 Rough Pump Manifold and Exhaust Connections ............B-16 B-12 Rough Pump Manifold and Exhaust Connections ............B-18...
  • Page 11 Models 947, 948 and 960 Leak Detectors Operations and Service Manual List of Tables Table Description Page Valve Operation ......................... 2-3 J120 Input Connections ..................... 2-6 J121 Output Summary ....................... 2-7 J123 Pinout Summary......................2-8 NOT READY Condition Codes ..................3-11 Scheduled Maintenance ....................
  • Page 12 Models 947, 948 and 960 Leak Detectors Operations and Service Manual This page intentionally left blank.

  • Page 13: Declaration Of Conformity

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual to which this declaration relates is in conformity with the following standard(s) or other normative documents.

  • Page 14: Warranty

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Warranty Products manufactured by Seller are warranted against defects in materials and workmanship for twelve (12) months from date of shipment thereof to Customer, and Seller’s liability under valid warranty claims is limited, at the option of Seller, to repair, to replace, or refund of an equitable portion of the purchase price of the Product.

  • Page 15: Factory Calibration Data

    Serial Number: Initials: Your Varian 947/948/960 leak detector has been thoroughly tested prior to shipment. It is shipped tuned to helium on Filament No. 1. Normally, once set, the tuning adjustments are left untouched and calibration may be verified as required.

  • Page 16: Hazard And Safety Information

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Hazard and Safety Information This manual uses the following standard safety protocols: The warning messages are for attracting the attention of the WARNING operator to a particular procedure or practice which, if not followed correctly, could lead to serious injury.

  • Page 17: Solvents

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Solvents The mechanical components of leak detectors are typically CAUTION cleaned with alcohol, methanol, or other solvents. When heated, sprayed, or exposed to high-temperature equipment, these solvents become flammable and explosive, causing serious injury or death.

  • Page 18: Equipment, General

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Equipment, General The leak detector is not designed for use with hazardous gases. WARNING Verify that the system to be tested has been purged of all hazardous gases prior to using the leak detector.When testing a...
  • Page 19 Models 947, 948 and 960 Leak Detectors Operations and Service Manual WARNING Electrical insulation must include the appropriate branch circuit (at least 20 A), with long time delay and a reliable earth ground. Do not use an extension cord. Use only the power cord that was provided with your leak detector.

  • Page 20: Vacuum Equipment And Cleanliness

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Vacuum Equipment and Cleanliness Cleanliness is vital when servicing the leak detector or any vacuum equipment. There are some techniques that are more important in leak detector servicing than in general vacuum work: Do not use silicone oil or silicone grease.

  • Page 21: Spectrometer Tube

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual VacuSolv, included in the Component and Spectrometer Tube NOTE Cleaning Kit (Part No. 670029096), is recommended for cleaning the spectrometer tube components. VacuSolv can also be used for fine cleaning of other parts in the leak detector’s vacuum system, such as valves and fittings.

  • Page 22: Varian Services

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Varian Services The following are just a few of the many services that Varian offers its customers. Please see our catalog, or contact us to learn of the services that are available. Contact Varian Vacuum Technologies Customer Service at 1-800-8VARIAN for details.
  • Page 23 Vacuum system (960 uses conventional flow) Platform electronics Front panel and indicators The 947/948/960 can be configured with dry or wet pumps. The 948/960 have a nitrogen cold trap. The platform electronics, service pendant, and displays are located in the turret. Leak rate and system status information is displayed on the front panel, and is also available through the rear panel I/O.
  • Page 24 Models 947, 948 and 960 Leak Detectors Operations and Service Manual The Model 947 is shown in Figure 1-1. Descriptions of the turret and operational buttons identified in Figure 1-1 follow the figure. Models 948/960 are shown in Figure 1-2. Figure 1-1 947 Leak Detector...
  • Page 25 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Models 948/960 are shown in Figure 1-2. The door on the working surface of the 948/960 provides access to the nitrogen cold trap. Descriptions of the turret, operational buttons, and nitrogen trap identified in Figure 1-2 follow the figure.

  • Page 26: Platform Electronics

    Refer to the Unpacking Instructions located on the outside of the shipping container before opening the container. The 947/948/960 are carefully packed onto a shock absorbing skid and enclosed by a heavy cardboard container banded to the skid. The factory packing provides maximum protection during shipment.

  • Page 27: Removing The 947/948/960 From The Skid

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 5. Remove any loose boxes or packages and put them aside. Keep the original packing for re-use in the event that it is necessary to return the leak detector to Varian Vacuum Technologies.

  • Page 28: Removing Loose Packing From Interior Of 947/948/960

    Once the 947/948/960 is off the skid, the loose packing inside the enclosure must be removed. 1. Open the front panel of the 947/948/960, which is the main access to service the pumps and the spectrometer tube. 2. Take out and remove all loose packing from inside the leak detector.
  • Page 29 Models 947, 948 and 960 Leak Detectors Operations and Service Manual System Pressure Displays system pressure monitored at the inlet of the spectrometer Bar Graph tube on a 20-segment bar graph. The green portion of the graph indicates normal operating vacuum level.

  • Page 30: Inner Door Instruction Label

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Auto Cal Button Press to initiate automatic calibration check. The system must be in TEST mode to initiate Auto Cal. During the check, all front panel pushbuttons are disabled. The 947/948/960 transitions back to TEST mode at the completion of the Auto Cal routine.

  • Page 31: Rear Panel Power Connection And Circuit Breakers

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 1.5 Rear Panel Power Connection and Circuit Breakers Figure 1-5 shows the rear power panel of the 947/948/960. Descriptions of the rear panel elements follow the figure. Figure 1-5 Rear Power Panel...

  • Page 32: Service Pendant

    LCD display (see Figure 1-6). The service pendant is stored in the turret and connects to the 947/948/960 using a six-foot cable that connects to an RS-232 serial port (J1, a 9-pin D sub connector) located inside the lockable turret.

  • Page 33: Installation Preparation

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 1.7 Installation Preparation To prepare the 947/948/960 for operation: Have power and liquid nitrogen (948/960 only) available Check oil level of wet pumps Adhere to special installation requirements for a clean room (if required) Set up an appointment for Installation services (see page 1-12) 1.7.1 Power...

  • Page 34: Liquid Nitrogen (Models 948/960 Only)

    1.7.3 Oil-Sealed Vacuum Pumps The 947/948/960 is available with either dry or wet (oil-sealed) mechanical pumps. Units built with oil-sealed pumps are shipped with the proper initial charge of oil, however, the oil level should be checked after the pumps have been running for at least ten minutes. On the front of each of the roughing and forepumps is an oil level sight glass.

  • Page 35: Storage

    Section 3, “Operation” on page 3-1, of this manual for operating instructions. 1.9 Optional Rear Panel Interface Connections Figure 1-7 shows the optional rear interface connection panel of the 947/948/960. Descriptions of the rear panel connectors follow the figure. Figure 1-7 Rear Panel Interface Connectors...
  • Page 36 Models 947, 948 and 960 Leak Detectors Operations and Service Manual This page intentionally left blank.

  • Page 37: Section 2. Leak Detector Integration

    Although Models 947/948/960 are considered stand-alone units, all the models can be incorporated into a production line connected to a host computer or PLC. This section details the setup and operation of Models 947/948/960 into a production line, or for use as automated equipment, rather than stand-alone equipment.
  • Page 38 Models 947, 948 and 960 Leak Detectors Operations and Service Manual In Figure 2-1 and Figure 2-2 on page 2-4, valves are designated by numbers in white circles ( ), other key parts of the vacuum system are designated by numbers in black circles ( ).
  • Page 39 Table 2-1 serves two purposes. In the upper portion, the valve name and type are defined. In the lower portion, Table 2-1 indicates the valve state (open or closed) in relation to the system status for testing the 947/948/960. The following abbreviations are used in Table 2-1: V=Vacuum...
  • Page 40 Models 947, 948 and 960 Leak Detectors Operations and Service Manual In Figure 2-2, numbers in white circles designate the location of valves. Other key parts of the vacuum system, represented by numbers in black circles, are identified after Figure 2-2.
  • Page 41 Models 947, 948 and 960 Leak Detectors Operations and Service Manual In Figure 2-3, numbers in white circles designate the location of valves. Other key parts of the vacuum system, represented by numbers in black circles, are identified after Figure 2-3.

  • Page 42: Electronic Considerations For The Optional Rear Panel Interface

    2.3 Electronic Considerations for the Optional Rear Panel Interface This section includes information necessary to interface the 947/948/960 with a PLC or a host computer using either serial or parallel communications through the optional rear panel interface via J120 Discrete I/O, J121 BCD Outputs and J123 Host Serial Port.

  • Page 43: Bcd J121 Outputs

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Table 2-2 J120 Input Connections (Continued) Description Pin on Input Name Momentary or Level J120 Ready Active High Active when system is operating (inverse of “Not Ready”). Ground return for J120 only...

  • Page 44: Host Serial Port J123 Pinouts

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 2.3.3 Host Serial Port J123 Pinouts The Host Serial Port is used to interface the 947/948/960 to a PLC or host computer via an RS-232 connection. Table 2-4 provides details about the connection.

  • Page 45: Optional Interface Connections

    The rear panel connectors are shown in Figure 2-4. Figure 2-4 Rear Panel 2.4.1 Grounding and Isolation The service, remote, and rear panel RS-232 ports in the 947/948/960 are referenced to the chassis ground and to the system ground.

  • Page 46: Setup

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 2.4.2 Setup Parameters relating to the operation and performance of the 947/948/960 Platform are stored in EPROM. These parameters can be viewed and changed via the service pendant or rear serial ports.
  • Page 47 Models 947, 948 and 960 Leak Detectors Operations and Service Manual If the I/O on J120 is used, then: +5 VDC to +24 VDC must be applied to J120, pins 27 and 28. The +5 VDC to +24 VDC return must be connected to J120, pins 1 and 25.

  • Page 48: Operation Using The Optional Rear Panel Interface

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 2.5 Operation using the Optional Rear Panel Interface Once setup is complete and the 947/948/960 is warmed up, operation can be turned over to the discrete I/O by asserting the PARALLEL ENABLE input (J120 pin 6). Operations can be monitored using the front panel display, or via a PLC.

  • Page 49: Section 3. Operation

    Section 3. Operation To obtain accurate readings using the 947/948/960 leak detectors, follow the operational procedures listed in this section. The 947/948/960 measure the leak rate in atm cc/sec. The procedures explain how to: Start and warm up the 947/948/960.
  • Page 50 Models 947, 948 and 960 Leak Detectors Operations and Service Manual During operation, the LED functions are illuminated to indicate the operation being performed. The definitions of the operations are as follows: VENT Illuminates when the vent valve is open. The LED is off when the valve is closed.

  • Page 51: Initial System Parameter Setup

    Manual Range is used to force the 947/948/960 to display a leak rate in only one decade (the exponent never changes). This feature is useful when the test operator is only concerned with monitoring the leak rate measurement within a single decade.
  • Page 52 Models 947, 948 and 960 Leak Detectors Operations and Service Manual RANGE STOP The RANGE STOP feature configures the 947/948/960 so that it only auto-ranges down to the pre-selected decade entered in the range stop variable field. For example, if RANGE STOP is enabled and set to −07, then the most sensitive range that the leak detector...
  • Page 53 Models 947, 948 and 960 Leak Detectors Operations and Service Manual REJECT SET POINTS The REJECT SET POINTS are used to alert the operator that a mea- sured leak rate has exceeded the set value. There are four set points available.
  • Page 54 Models 947, 948 and 960 Leak Detectors Operations and Service Manual A Pass condition is indicated by the system reverting to the VENT mode upon completion of the test cycle. A fail condition results in REJECT being displayed in the LED display area, and a reject set point activation upon completion of the test cycle.
  • Page 55 This is a function of the part configura- tion and the leak rate specification. In AUTO SEQUENCER mode, the 947/948/960 remains in test for the entire duration of the prese- lected test time. FINE TEST MODE...

  • Page 56: Start-Up

    To operate the 947/948/960, you need: Test fixtures appropriate to the unit under test Helium tank with spray gun or hook up for auto test (Helium for the 948/960) Figure 3-2 shows the important 947/948/960 operation controls for start up and power. For circuit breaker descriptions, refer to “Rear Panel Power Connection and Circuit Breakers”...
  • Page 57 Refer to Figure 3-2 and follow the start up procedure, listed in the next Section, and in “Calibration and Sensitivity Checks” on page 3-11 procedure to put the 947/948/960 in a Ready for Operation state from the All Systems off condition.

  • Page 58: Startup Procedure

    3. Turn on the Detector switch. 4. Models 948/960 only: When the system pressure bar graph drops into the green range (see Figure 1-3 on page 1-6), fill the cold trap with liquid nitrogen. Liquid nitrogen causes burns upon contact. Use appropriate...

  • Page 59: Calibration And Sensitivity Checks

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 3.4 Calibration and Sensitivity Checks At the beginning of each workday or shift, or as conditions require, verify 947/948/960 integrity by performing the Calibration and Sensitivity Check procedure. Compliance with this procedure prepare your detector for normal daily operation.

  • Page 60: Calibration And Sensitivity Checks

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 3.4.1 Calibration and Sensitivity Checks To perform calibration and sensitivity checks: 1. Warm up the 947/948/960 for 30 minutes. 2. Place the test port plug in the test port opening .

  • Page 61: Operating Procedures

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 9. Be sure the TEST LED is on, and press the AUTO CAL button. Do not continue if a condition code is displayed. Consult the NOT READY Condition Code Chart Table 3-1 on page 3-11 and follow instructions.

  • Page 62: Auto Ranging

    The LEAK RATE range exponent goes to the most appropriate range. 4. Introduce helium to the unit under test. The 947/948/960 automatically traces the under test helium signal up range through the Reject Set Point. If larger than the pre-set Reject value, the leak rate signal reads this maximum level.

  • Page 63: Manual Ranging

    3. Press the SMALLER or LARGER button to select the exponent of the leak rate range to which you want to test. 4. Securely attach the new unit under test to the test port while the 947/948/960 is in VENT mode.

  • Page 64: Standby

    When continued use of 947/948/960 is not anticipated, STANDBY mode, a partial shutdown, can be used to save energy. To put the 947/948/960 into STANDBY mode: 1. Press the VENT button and hold it until the Vent LED comes on.

  • Page 65: Using The Pendant For Parameter Setup

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 3.8 Using the Pendant for Parameter Setup The service pendant is stored in the turret and is connected to Models 947/948/960 at J1 in the turret for parameter changes, monitoring, or diagnostics. The pendant must be connected to the 947/948/960 to operate any of the functions.

  • Page 66: Optional Discrete I/O

    Refer to Section D, “Inputs and Outputs” on page D-1 for detailed information. When operating the 947/948/960 from the optional discrete I/O, it is necessary to make the PARALLEL ENABLE (J120 pin 6) active. This allows the leak detector to accept commands from the other discrete I/O inputs.

  • Page 67: Section 4. Maintenance

    For heavy production use, more frequent overhauls are needed. In most cases, this work is done by user maintenance personnel, but it may also be done by Varian Vacuum Technologies under the terms of a service contract.
  • Page 68 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Cleanliness is vital when servicing the leak detector or any vacuum equipment. The following are especially important in the servicing of leak detectors: Do not use silicone oil or silicone grease.
  • Page 69 See “Spare Parts” on page 4-34 for more information. The 947/948/960 must be calibrated to verify sensitivity at least once a day. However, other functions may be carried out more or less often, depending on the frequency of use.
  • Page 70 Models 947, 948 and 960 Leak Detectors Operations and Service Manual On-demand maintenance functions are listed in Table 4-2. Table 4-2 As-Required Maintenance Most Common Symptom Refer to Trap almost empty, nearly 14 hours without a refill. “Liquid Nitrogen Cold Trap (Models 948/960 only)” on page 4-10 Preamplifier failure.

  • Page 71: Daily Maintenance

    To perform a calibration check: 1. Press the STD LEAK button. 2. Compare the value displayed on the 947/948/960 to the value of the known calibrated leak listed on the label on the top of the turret. Refer to Figure 1-1 on page 1-2 for the location of the label.

  • Page 72: General Suggestions For Leak Checking

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.1.1.2 General Suggestions for Leak Checking The following suggestions apply whether leak checking components, systems, or the leak detector itself: 1. When spraying suspected leak locations: Always apply helium sparingly.

  • Page 73: Yearly Maintenance

    Helium calibrated leaks typically degrade at 3 percent per year. The calibrated leak supplied with your 947/948/960 must be checked at least once a year to ensure it is at the value stated on its label. Failure to check the leak could result in unreliable testing. You can arrange for testing and re-calibration at a lab of your choice.
  • Page 74 Models 947, 948 and 960 Leak Detectors Operations and Service Manual To remove the internal calibrated leak: 1. Disconnect the mains power supply and make sure all pumps are off. Disconnect power from the 947/948/960 before performing any WARNING maintenance procedure that requires physically disconnecting any part of the system.

  • Page 75: Replacing The Internal Calibrated Leak

    6. Turn the leak detector on and wait for the pumps to come up to speed. 7. Models 948/960 only: Once the system has pumped down, clean and fill the Liquid Nitrogen Cold Trap using the procedure described in “Liquid Nitrogen Cold Trap (Models 948/960 only)”...

  • Page 76: Liquid Nitrogen Cold Trap (Models 948/960 Only)

    6. Once the trap is clean, replace it in the 948/960, and close the vent valve on the top of the Liquid Nitrogen trap. 7. To re-establish operation, carefully refill the trap with LN , using the safety procedure above, and follow normal startup procedures for Models 948/960.

  • Page 77: Spectrometer Tube Overhaul

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.4 Spectrometer Tube Overhaul Spectrometer tube overhaul consists of removing, cleaning, and re-installing the 947/948/960 Spectrometer Tube Assembly. Liquid nitrogen causes burns upon contact. Use appropriate WARNING protective devices, including heavy loose gloves and eye or face shields.

  • Page 78: Removal Of The Spectrometer Tube And Preamplifier

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.4.1 Removal of the Spectrometer Tube and Preamplifier Refer to Figure 4-2 for the removal of the 947/948/960 spectrometer tube. Liquid nitrogen causes burns upon contact. Use appropriate WARNING protective devices, including heavy loose gloves and eye or face shields.
  • Page 79 Models 947, 948 and 960 Leak Detectors Operations and Service Manual 6. Disconnect all four electrical connections to the spectrometer tube To remove the locking connector shown in Figure 4-2, NOTE both metal tabs at the left of the connector must be pushed to unlock the connector, then pull the connector to the right to remove it.

  • Page 80: Disassembly Of The Spectrometer Tube And Preamplifier

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.4.2 Disassembly of the Spectrometer Tube and Preamplifier To disassemble the spectrometer tube: 1. Remove the four screws on the spectrometer tube (Figure 4-3), noting the placement of the grounding strap The grounding strap must go back on the same screw during reassembly.
  • Page 81 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Figure 4-3 Spectrometer Tube Disassembly Store the Ion Source in a cool, dry area in a tightly sealed WARNING container. Wash hands thoroughly after handling the Ion Source and especially before smoking or eating.

  • Page 82: Spectrometer Tube Cleaning

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.4.3 Spectrometer Tube Cleaning To clean the spectrometer tube: ™ 1. Use the Scotch-Brite flexible abrasive pads from the spectrometer cleaning kit to remove heavy deposits from the ground slit plate, and spectrometer tube body.
  • Page 83 Models 947, 948 and 960 Leak Detectors Operations and Service Manual 6. Put the heater cartridge back in its cavity (Figure 4-5). Figure 4-5 Spectrometer Tube Reassembly (Ground Slit Plate) 7. With the new O-rings on each of the two deflection pole pieces...
  • Page 84 Models 947, 948 and 960 Leak Detectors Operations and Service Manual 10. Fit the magnet assembly back onto the spectrometer tube body. 11. With the grounding strap attached to the same screw from which it was removed, replace and tighten the four screws that fit into the magnet assembly.

  • Page 85: Reinstallation Of The Spectrometer Tube

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.4.5 Reinstallation of the Spectrometer Tube Liquid nitrogen causes burns upon contact. Use appropriate WARNING protective devices, including heavy loose gloves and eye or face shields. Models 948/960 only: Before servicing the Spectrometer Tube, NOTE refer to “Liquid Nitrogen Cold Trap (Models 948/960 only)”...

  • Page 86: Air Filter

    4. Models 948/960 only: Fill the Liquid Nitrogen Cold Trap using the procedure described in “Liquid Nitrogen Cold Trap (Models 948/960 only)” on page 4-10, steps 5 and 6. 5. Reconnect power and start the leak detector and refer to the “Calibration and Sensitivity Checks”...

  • Page 87: Spectrometer Tube Exchange

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.6 Spectrometer Tube Exchange The spectrometer tube replaceable parts consist chiefly of the ion source, the preamplifier, the magnetic poles, and the spectrometer tube as a complete assembly. Because of the complexity and sensitivity of the preamplifier,...
  • Page 88 Allow the pumps to warm up if the detector has been off for some time. 7. Models 948/960 only: Once the system has pumped down, clean and fill the Liquid Nitrogen Cold Trap using the procedure described in “Liquid Nitrogen Cold Trap (Models 948/960 only)”...

  • Page 89: Tc1 And Tc2 Gauge Replacement And Calibration

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.7 TC1 and TC2 Gauge Replacement and Calibration 4.2.7.1 Replacement of the TC1 Gauge in the Main Valve Block Assembly Figure 4-10 shows the valve block removed from the system.
  • Page 90 Models 947, 948 and 960 Leak Detectors Operations and Service Manual 6. Examine the O-ring for wear. If necessary, use a new O-ring, otherwise clean the O-ring. Before re-using O-rings or installing new O-rings, wipe them NOTE down with a lint-free cloth before installation to ensure that no foreign matter is present to impair the seal.

  • Page 91: Replacement Of The Tc2 Gauge In The Service Block Assembly

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.7.2 Replacement of the TC2 Gauge in the Service Block Assembly Liquid nitrogen causes burns upon contact. Use appropriate WARNING protective devices, including heavy loose gloves and eye or face shields.
  • Page 92 14. Place the plug connector onto the thermocouple gauge. The center post is keyed so it only goes on one way. 15. Models 948/960 only: Refill the Cold Trap using the procedure described in “Liquid Nitrogen Cold Trap (Models 948/960 only)” on page 4-10.

  • Page 93: Thermocouple Gauge Calibration Procedures

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.7.3 Thermocouple Gauge Calibration Procedures Use the Service Pendant to perform a calibration on either the system pressure thermocouple (TC2) or the test port thermocouple gauge (TC1). Refer to Section A, “Service Pendant Keypad Functions”...

  • Page 94: Atmospheric Calibration

    1. Once the system thermocouple (TC2) has been replaced and before powering up the leak detector, turn off the ROUGH pump and DETECTOR switches. 2. Turn on the power switch located on the rear panel of the 947/948/960. 3. Wait for the system NOT READY LED to illuminate.

  • Page 95: Test Port Pressure Gauge (Tc1) Calibration

    6. Wait approximately five minutes for the vacuum system pressure to stabilize. 7. Adjust the Tuning Leak to 100 mTorr as indicated by the Varian 801 and verify that the test port pressure on the test port pressure graph reads 1.0E-01 Torr.

  • Page 96: Atmospheric Calibration

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 9. Type XYZZY<CR>, then 100 INIT-TPTCZERO<CR>. The system should respond OK. The test port pressure on the test port pressure bar graph should read 1.0E-01 Torr. A FAILED response on the PC is an indication that the calibration was not successful.

  • Page 97: Rough Pump And Forepump Oil Level Check (Oil-Sealed Mechanical Pumps)

    (Figure 4-12). Refer to your pump manual for the proper oil level. If it is low, fill it to the proper level with Varian Vacuum Technologies’ pump oil (part no. 695409005).

  • Page 98: Condition Of Oil (Oil-Sealed Mechanical Pumps)

    4.2.9 Cleaning the Test Port The test port is located at the front center of Models 947/948/960. Thus, it is not necessary to turn the leak detector off or disconnect it from mains power if this is the only procedure being performed.

  • Page 99: Examining And Cleaning The Test Port

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 2. Remove the test port compression ring and O-ring from the top of the test port (Figure 4-14). Figure 4-14 Remove the Test Port Compression Ring and O-ring 4.2.9.2 Examining and Cleaning the Test Port To perform this procedure: 1.

  • Page 100: Replacing The Test Port

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4.2.9.3 Replacing the Test Port To replace the test port: 1. Place the O-ring into the groove of the compression ring. 2. Place the compression ring and O-ring onto the top of the test port (Figure 4-15).

  • Page 101: Replacement Parts

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Table 4-4 lists the exchange assembly parts. Table 4-4 Exchange Assembly Parts Section Description Part Number Spectrometer Tube Re-gaussed Magnet GGK9814301 Re-built Spec Tube GGK9735301 Vacuum System V70 Turbo Pump...
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  • Page 103: Section 5. Troubleshooting

    Verify that the leak detector is plugged into an appropriately powered and properly grounded receptacle. Verify that all plugs and connectors are firmly seated (spectrometer tube, electronic cables, pumps, and power supplies). For information about pumps shipped with your 947/948/960, refer to the pump manual that came with your 947/948/960 leak detector.

  • Page 104: Error Condition Codes

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 5.1 Error Condition Codes Use Table 5-1 to identify the problem by condition code or Figure 5-2 to identify the symptom. Table 5-1 Error Condition Codes Code Problem Area...

  • Page 105: Troubleshooting Symptoms And Solutions

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 5.2 Troubleshooting Symptoms and Solutions Table 5-2 lists the particular symptoms encountered when troubleshooting the leak detector. For every symptom, there is a list of possible causes and actions you can take to remedy the situation.
  • Page 106 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Table 5-2 Troubleshooting (Continued) Symptom Check For Corrective Action Pumps is gurgling Pump oil is low. Add oil. KF clamps are loose. Tighten the clamps. Forepump manifold or vacuum Check for leaks.

  • Page 107: Appendix A. Service Pendant Keypad Functions

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Appendix A. Service Pendant Keypad Functions A.1 Keypad Functions Figure A-1 shows the service pendant keypad. “Glossary of Function Keys” on page A-3 explains the keys that perform special functions when entering information.

  • Page 108: Using The Service Pendant

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual A.1.1 Using the Service Pendant Each function is printed in black in the center of the key (for example, REJ#). Some functions require the input of a number before the function key is pressed. Other functions, such as queries, do not require any numeric input.

  • Page 109: Glossary Of Function Keys

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual A.2 Glossary of Function Keys Performs the red function on the key pressed after the SHIFT key. SHIFT LK RATE Enters the E for exponential notation inputs such as reject set point.

  • Page 110: Glossary Of Input And Data Keys

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual A.3 Glossary of Input and Data Keys The keys listed below start at the top of the keypad and continue from left to right. Displays the value of the range stop, the lowest decade that the RNG ST leak detector will show on the bar graph.
  • Page 111 Models 947, 948 and 960 Leak Detectors Operations and Service Manual EMIS Displays the value of the Emission Current in the Ion Source. [SHIFT] SHOW GAIN TURBO SHOW Displays the value of the Ion Voltage in the Ion Source. ION V TURBO Displays the status of the Turbo Pump in the leak detector.
  • Page 112 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Sets a permanent new value for System Gain. Enter X.X INIT (the desired value), followed by the SHIFT key, then the [SHIFT] GAIN function key. INIT Sets a temporary new value for Emission Current. Enter XXXX EMIS (the desired value), then the function key.
  • Page 113 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Sets the value of the Auto Sequencer Test Time. Enter XXX (the desired value), followed by the SHIFT key, then the [SHIFT] TST TM SHOW function key. Displays the value of the Auto Sequencer Roughing Time.
  • Page 114 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Sets the leak rate value to which the leak detector calibrates. Enter X.XE-X (the desired value), followed by the SHIFT key, then the [SHIFT] STD LK SHOW function key.

  • Page 115: Appendix B. Parts Replacement

    “Replacing the Rough Pump” on page B-15 “Replacing the Forepump” on page B-22 B.1 Removing the Covers Before opening any part of Models 947/948/960 for service, heed the following: Disconnect power from the 947/948/960 before performing any WARNING maintenance procedure that requires physically disconnecting any part of the system.

  • Page 116: Opening The Turret

    1. Loosen the screws of the service pendant serial connection and remove the connection (Figure B-1). The service pendant power cable is still attached to the NOTE electronics housed beneath the pendant shelf. 2. Place the service pendant on the top of the 947/948/960 or on another nearby surface. Screw Serial Connection Screw Figure B-1 Removing the Service Pendant Shelf 3.

  • Page 117: Removing The Top Panel

    B.1.2 Removing the Top Panel The top panel is one piece that includes the turret and its door, a covering of the sides of the control and display panel, and the stainless steel top of the 947/948/960. To remove the 947/948/960 top panel: 1.

  • Page 118: Replacing All Panels And Covers

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 6. Remove the three, 5-16 screws from under the front of the top cover (Figure B-4). Screw Screw Screw Figure B-4 The Top Panel from the Front of the 947/948/960 7.

  • Page 119: Replacing The Top Panel

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.1.3.2 Replacing the Top Panel Be sure power is disconnected from the leak detector before WARNING attempting to replace the top cover. The start button could be pressed while maneuvering the cover into place and the leak detector inadvertently started.

  • Page 120: Replacing The Ion Source

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.2 Replacing the Ion Source If the ion source needs replacement (Figure B-5), replace it during spectrometer tube cleaning. Adjustment is required after replacement is complete. Refer to “Calibration and Sensitivity Checks”...
  • Page 121 This can occur from a system pressure leak or transferring into test at too high a pressure. 5. Discard the ion source in accordance with local regulations, or return it to Varian Vacuum Technologies for exchange.
  • Page 122 Models 947, 948 and 960 Leak Detectors Operations and Service Manual 11. When installing the ground slit plate, be sure that the snap prongs are facing up. Align the slit at 90° with the side wall of the spectrometer tube and concentrically align the circular hole in the plate with the smaller guide hole in the bottom of the ion source cavity.

  • Page 123: Replacing The Turbo Pump

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.3 Replacing the Turbo Pump Models 947/948/960 have one turbo pump and two mechanical pumps: a forepump and a rough pump. B.3.1 Turbo Pump The turbo pump (Figure B-6) is located in the middle front of the main cabinet. You must remove connections to the valve block, spectrometer tube and power to remove the turbo pump.

  • Page 124: Removing The Turbo Pump

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.3.1.1 Removing the Turbo Pump To replace the turbo pump: 1. Disconnect the mains power supply and make sure that all pumps are off. Disconnect power from the 947/948/960 before performing any...
  • Page 125 Models 947, 948 and 960 Leak Detectors Operations and Service Manual 4. Follow the power wire from the fan to two pink connectors labeled 1+ and 2−. If the connections are not fully labeled, label them now (Figure B-8). Fan Power...

  • Page 126: Replacing The Turbo Pump

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 6. Loosen the wing nut and remove the NW25 clamp that connects the foreline to the turbo (Figure B-7 on page B-10). 7. Remove the centering ring and O-ring and place them on a clean surface.

  • Page 127: Connecting The Turbo Pump To The Svba

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 3. Before re-using O-rings or installing new O-rings, wipe them down with a lint-free cloth to ensure that no foreign matter is present to impair the seal. Remove O-rings carefully with your fingers. Do not use metal CAUTION tools for this task.
  • Page 128 17. Turn the leak detector on and wait for the system to be ready. Allow the pumps to warm up if the detector has been off for some time. 18. Calibrate the 947/948/960 using the procedure described in “Re-calibrate the Internal Calibrated Leak” on page 4-7.

  • Page 129: Replacing The Rough Pump

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.4 Replacing the Rough Pump B.4.1 Wet Systems This discussion includes procedures for replacing rough pumps in wet systems (“Removing the Wet System Rough Pump” on page B-16) and rough pumps in dry systems (“Removing the Dry System Rough Pump”...

  • Page 130: Removing The Wet System Rough Pump

    4. Disconnect the pump power plug from the 947/948/960. 5. Drain the oil according to the pump manual instructions. 6. If you are replacing the pump as part of a Varian exchange program, return it in accordance with the program, or discard it in accordance with all applicable regulations.

  • Page 131: Replacing The Wet System Rough Pump

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual 8. Remove the centering ring and O-ring and place all connections where the oil will not contaminate other parts. 9. Remove the NW16 clamp from the exhaust connection. 10. Remove the exhaust fitting.

  • Page 132: Re-Installing The Wet System Rough Pump

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.4.1.1.3 Re-installing the Wet System Rough Pump To avoid injury, use proper lifting techniques when moving WARNING pumps. Your system may have pumps that require two people to move them safely.
  • Page 133 Allow the pumps to warm up if the detector has been off for some time. 18. Models 948/960 only: Once the system has pumped down, clean and fill the Liquid Nitrogen Cold Trap using the procedure described in “Liquid Nitrogen Cold Trap (Models 948/960 only)”...

  • Page 134: Dry Systems

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.4.2 Dry Systems B.4.2.1 Removing the Dry System Rough Pump To perform this procedure: 1. Disconnect the mains power supply and make sure that all pumps are off. Disconnect power from the 947/948/960 before performing any...

  • Page 135: Replacing The Dry System Rough Pump

    1. Ensure the area is clean for the new pump. 2. Place the new pump in the 947/948/960 oriented as shown in Figure B-10 on page B-15, placing the mounting bolts into the holes in the floor of the cabinet.

  • Page 136: Replacing The Forepump

    Allow a new pump to run for one hour and then perform an NOTE autocal. 16. Models 948/960 only: Once the system has pumped down, clean and fill the Liquid Nitrogen Cold Trap using the procedure described in “Liquid Nitrogen Cold Trap (Models 948/960 only)” on page 4-10.

  • Page 137: Removing The Wet System Forepump

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.5.1.1 Removing the Wet System Forepump To perform this procedure: 1. Disconnect the mains power supply and make sure that all pumps are off. Disconnect power from the 947/948/960 before performing any...

  • Page 138: Replacing The Wet System Forepump

    1. Ensure the area is clean for the new pump. 2. Place the new pump in the 947/948/960 oriented as shown in Figure B-10 on page B-15, placing the mounting bolts into the mounting holes in the bottom of the cabinet.
  • Page 139 Allow the pumps to warm up if the detector has been off for some time. 19. Models 948/960 only: Once the system has pumped down, clean and fill the Liquid Nitrogen Cold Trap using the procedure described in “Liquid Nitrogen Cold Trap (Models 948/960 only)”...

  • Page 140: Dry System

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.5.2 Dry System B.5.2.1 Removing the Dry System Forepump To perform this procedure: 1. Disconnect the mains power supply and make sure that all pumps are off. Disconnect power from the 947/948/960 before performing any...

  • Page 141: Removing The Nitrogen Purge Connection From Pump

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual B.5.2.1.2 Removing the Nitrogen Purge Connection from Pump An electrician or electrical technician is required for proper NOTE removal and installation. If only maintenance is being performed, the pump can be removed with the valve attached.

  • Page 142: Re-Installing The Dry System Forepump

    1. Ensure the area is clean for the new pump. 2. Place the new pump in the 947/948/960 oriented as shown in Figure B-10 on page B-15, and the mounting bolts into the holes in the floor of the cabinet.

  • Page 143: Replacing The Exhaust Fitting

    Allow a new pump to run for one hour and then perform an NOTE autocal. 7. Models 948/960 only: Once the system has pumped down, clean and fill the Liquid Nitrogen Cold Trap using the procedure described in “Liquid Nitrogen Cold Trap (Models 948/960 only)” on page 4-10.
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  • Page 145: Appendix C. Communications Protocol

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Appendix C. Communications Protocol This appendix defines the technical specifications for the RS-232 protocol to be used with the 947/948/960 Leak Detection System optional rear panel interface. C.1 Protocol (RS-232) The RS-232 ports operate at 9600 baud, 8 bits, no parity, and one stop bit.
  • Page 146 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Table C-1 through Table C-4 outline the available control and query commands. Table C-1 lists inquiries used to determine internal operating parameters. All inquiries, except VER, begin with and end with <CR>.
  • Page 147 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Table C-1 Internal Operating Parameters (Continued) Inquiry Response ?LEAK An eight-character number consisting of a three-digit leak rate mantissa with decimal point after the first digit followed by E–, then a two-digit number, which is the leak rate range exponent (e.g., 1.35E-07).
  • Page 148 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Table C-1 Internal Operating Parameters (Continued) Inquiry Response ?SETUP Eight lines that report a summary of setup parameters. Each line begins with a <CR><LF>. The format is as follows:...
  • Page 149 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Table C-2 lists the commands used to set NON-VOLATILE operating parameters. The current value of the operating parameter is changed to a new value. If parallel enable is asserted, the response is cant <CR>...
  • Page 150 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Table C-2 Non-volatile Operating Parameters (Continued) Command Response INIT-RANGESTOP Sets the most sensitive range exponent attainable when the feature is operating. Preceded by a minus sign and one or two digits (e.g., -08).
  • Page 151 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Table C-4 lists the commands used to cause leak detection actions. Table C-4 Command Parameters for Leak Detection Actions Command Action CALIBRATE Adjusts the Ion source parameters to cause a maximum response to helium, then adjusts the gain so that the current helium signal is the same as most recently input using INIT-STDLEAK.
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  • Page 153: Appendix D. Inputs And Outputs

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Appendix D. Inputs and Outputs The Table D-1 through Table D-5 list the signals available on the connector in the turret, and the various connectors of the optional rear panel interface.
  • Page 154 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Table D-2 Optional Discrete I/O Parallel Interface (J120) (Continued) Parallel Enable Active High Enables rear panel Input PLC Interface. Zero 200 msec high pulse Begins Auto Zero routine. Input...

  • Page 155: Bcd Discrete Output Parallel Interface (J121

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual D.2.2 BCD Discrete Output Parallel Interface (J121) The discrete I/O DB25 connector is used to control operations via a PLC. Table D-3 provides the J121 DB25 BCD connections. Table D-3 Optional BCD Discrete Output Parallel Interface (J121)

  • Page 156: Interface (J122) For Optional Universal Remote Control

    Input D.2.4 Host Serial Port (J123) The Host Serial Port connector is used to interface the 947/948/960 to a PLC or computer via an RS-232 DB25 connection. Table D-5 provides details about this connection. Table D-5 Optional Host Serial Port RS-232 Interface (J123)
  • Page 157 Models 947, 948 and 960 Leak Detectors Operations and Service Manual...
  • Page 158 Models 947, 948 and 960 Leak Detectors Operations and Service Manual...
  • Page 159 Models 947, 948 and 960 Leak Detectors Operations and Service Manual...
  • Page 160 Models 947, 948 and 960 Leak Detectors Operations and Service Manual...

  • Page 161: Appendix F. Accessories

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Appendix F. Accessories The accessories listed below can be purchased separately for use with the 947/948/960. Call Varian Vacuum Technologies for further information at 1-800-8VARIAN. Table F-1 947/948/960 Accessories...
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  • Page 163: Appendix G. Leak Detection Theory

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual Appendix G. Leak Detection Theory G.1 Leak Testing—Why is it Needed? Even with today's complex technology it is, for all practical purposes, impossible to manufacture a sealed enclosure or system that can be guaranteed leak proof without first being tested.

  • Page 164: Terminology

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual G.3 Terminology The following terminology has application throughout this manual: Flow atm cc/sec One cubic centimeter of gas per second at a pressure differential of one standard atmosphere (760 torr at 0 °C).

  • Page 165: Various Methods Of Testing For Leaks

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual G.4 Various Methods of Testing for Leaks There are many methods of testing for leaks in enclosures, systems or containers. The more commonly used methods and their accuracy ranges are listed below: −3...

  • Page 166: Helium Mass Spectrometer Leak Detection (Msld

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual G.5 Helium Mass Spectrometer Leak Detection (MSLD) Helium is an excellent trace gas because it is the lightest of the inert gases and as a consequence readily penetrates small leaks. In addition, its presence in the atmosphere is minute (5 PPM or 4 millitorr absolute).

  • Page 167: Facts About Leak Rates

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual G.5.4 Facts About Leak Rates −5 Visualizing Leaks in atm cc/sec: approximately 1 cc/day −7 Everyday Terms atm cc/sec: approximately 3 cc/year Audible or Visual Detection by Observer −4 a.

  • Page 168: Test Piece Evacuated

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual G.6.1 Test Piece Evacuated The object to be tested is evacuated by the leak detector roughing pump, then valved into the spectrometer vacuum system (see Figure G-1 and Figure G-2). The surface of the test object is then probed with a small jet of helium to locate individual leaks, or surrounded by helium (hooded) for an overall leak check.

  • Page 169: Test Piece Already Sealed

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual A sampling probe is connected to the leak detector. The object to be tested is filled with helium at the desired test pressure and the probe is moved over its surface. Some of the helium escaping from a leak is captured through the probe and enters the leak detector, thus locating the leak.

  • Page 170: Mass Spectrometer Leak Detector-Simplified Description

    Models 947, 948 and 960 Leak Detectors Operations and Service Manual G.7 Mass Spectrometer Leak Detector—Simplified Description The 947/948/960 consist of an analytical sensing tube called a spectrometer tube, electronics to operate the tube, and a vacuum system to maintain a very high vacuum within this tube (usually less than 0.1 millitorr or about one ten-millionth of ordinary...
  • Page 171 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Index J120 inputs 2-5 Parallel enable 2-11 Accessories available F-1 Parallel interface D-1 Air filter replacement 4-21 Dual mechanical pump configuration atm vs. std G-2 Gross test only 3-7...
  • Page 172 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Helium G-3 Radioisotope G-3 Hazard and safety information 1-iv Ultrasonic G-3 Helium for sealing G-7 Water immersion G-3 Helium mass spectrometer leak detection G-4 Leak testing G-1 Hermetic Auto ranging 3-13...
  • Page 173 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Tools and parts required 4-11 Audio reject set points 3-5 Manual ranging 3-14 Audio reject set points, enable / disable 3-5 Manual tuning 4-5 Auto-range 3-3 Mass spectrometer leak detector G-8...
  • Page 174 Models 947, 948 and 960 Leak Detectors Operations and Service Manual Scheduled maintenance 4-3 TC1 gauge replacement in MVBA 4-24 Sealing with helium G-7 TC2 gauge replacement in SBA 4-26 Sensitivity checks 3-12 Test mode indicator 3-2 Serial communications protocol B-1, C-1...
  • Page 176 India Fax: (44) 1932 22 8769 Tel: (91) 11 5548444 Brazil United States Fax: (91) 11 5548445 Varian Industria e Comercio Ltda. Varian Vacuum Technologies Italy Avenida Dr. Cardoso de Mello 1644 121 Hartwell Avenue Varian Vacuum Technologies Vila Olimpia...

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