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Kurt J. Lesker 979 Series, Operation And Maintenance Manual

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Series 979 ATV Transducer

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DAC2 Pressure to Voltage Table

Summary of Contents for 979 Series

Page 1: ...Operation and Maintenance Manual Series 979 Atmosphere to Vacuum Transducer ...

Page 2: ......

Page 3: ...Series 979 ATVTransducer Part 100014438 Series 979 Atmosphere to Vacuum Transducer ...

Page 4: ...ervice or additional information The part number can be found on your packing slip Both the part number and serial number are located on the bottom side of the housing For more information or literature contact Kurt J Lesker Company 1925 Route 51 Clairton PA 15025 3681 USA Phone 1 412 387 9200 1 800 245 1656 Fax 1 412 384 2745 2003 by the Kurt J Lesker Company All rights reserved ...

Page 5: ... Connection 19 Input Output Wiring 19 979 ATV Transducer Electrical Connections Table 20 Relay Inductive Loads and Arc Suppression 20 Operation 22 979 ATV Transducer Factory Defaults Table 22 RS 485 Protocol 23 Standard Addresses 23 Universal Addresses 23 Query and Command Syntax 23 Response Syntax ACK NAK 24 RS 485 Command Set 25 Set Up Commands 25 Active Filament AF 25 Address AD 25 Baud Rate BR...

Page 6: ...ction SD1 SD2 SD3 31 Enable Set Point EN1 EN2 EN3 32 Enable Control Set Point ENC 32 Set Point Status SS1 SS2 SS3 32 Protect Set Point PRO 32 Calibration Commands 33 Atmospheric Calibration ATM 33 Vacuum Calibration VAC 33 Gas Type Calibration GT 33 Gas Correction GC 34 Degassing the Sensor 35 Sensitivities Relative to Nitrogen 36 Gas Correction Factor Table 36 Analog Output 37 Pressure to Voltage...

Page 7: ...Series 979 ATVTransducer Accessories and Part Replacement 47 Notes 48 Appendix How the 979 ATV Transducer Works 49 Hot Cathode Ionization Sensor 49 Pirani Sensor 50 MicroPirani Sensor 51 ...

Page 8: ...Series 979 ATVTransducer ...

Page 9: ... for visible evidence of damage during shipment If anything has been damaged notify the carrier immediately Keep all shipping materials and packaging for claim verification If any items are missing from the package call Kurt J Lesker Customer Service at 1 412 387 9200 or 1 800 245 1656 Do not return the product to Kurt J Lesker unless specified to do so by Kurt J Lesker Customer Service Kurt J Les...

Page 10: ...k of electrical shock CAUTION Refer to the manual Failure to heed the message could result in personal injury serious damage to the equipment or both Calls attention to important procedures practices or conditions Symbols Used in this Manual ...

Page 11: ...ll of the electrical connector Do not turn on filament power when system pressure is above 5x10 2 Torr Hot Cathode sensor damage will result Do not operate with explosive gas mixtures or gases that are combustible in air The Hot Cathode sensor has a heated element and the MicroPirani uses a thin film Nickel element that is heated to a constant temperature above ambient Either of these could ignite...

Page 12: ...r plug in components Injury may result A qualified technician must perform any part replacement or internal adjustments Keep the unit free of contaminants Do not allow contamination of any kind to enter the unit before or during use Contaminants such as dust dirt lint glass chips and metal chips may permanently damage the unit ...

Page 13: ...um clad molybdenum yttria coated iridium 304 stainless steel 0 6 cm3 0 to 40o C 100o C Any EN 61326 1 EN 61010 1 1 OD tube mini CF 2 75 CF NW16 KF NW25 KF NW40 KF 2 9 x 3 1 x 4 4 74 x 79 6 x 112 mm 0 92 lbs 0 42 Kg Measuring range Set point range Analog out Maximum pressure Repeatability Typical Accuracy Typical Supply voltage Power consumption Relay contact rating Materials exposed to vacuum Hous...

Page 14: ...es when power is applied to the transducer filament The FILAMENT ON light can also be used in conjunction with the Test RS485 TST command described in the RS485 Command Set section to visually identify which sensor is set to a particular address This is useful when several transducers are connected to the same system The figure below shows the front view of the 979 ATV Transducer Feature and Contr...

Page 15: ... enables the system to monitor pressure as a procedure invisible to the user and when the desired pressure is reached trigger the next event in the system process This manual describes the installation and configuration tasks necessary to set up the 979 ATVTransducer After the device is set up a software engineer at the user s installation would use the communications protocol described in this ma...

Page 16: ...put as input to an automatic pressure controller Measure foreline and roughing pressures generated by mechanical vacuum pumps Control valves and pumps to automate pump down using relay set points Sense abnormal pressure and take appropriate security measures using relay set points Start or stop system processes with relay set points Measure pressures of backfilling gases ...

Page 17: ...e pressure values If the Hot Cathode sensor is going to be baked out the four screws on the panel closest to the flange will need to be removed see the Bakeout section for details Locate the sensor to ensure easy access to those four screws ENSURE EASY ACCESSTO REMOVE FOR BAKEOUT Orientation The 979 ATV Transducer can be installed and operated in any position without compromising accuracy Installi...

Page 18: ...vacuum port facing down to keep particulates or liquids from entering the device To prevent inaccurate pressure measurements shield an 979 located near an electron or ion source e g near an electron beam source or in a sputtering system and mount it away from strong magnetic fields Vacuum Connection The 979 ATV Transducer is available with the following flanges 2 75 CF rotatable 1 33 CF rotatable ...

Page 19: ...e with the end for power supply connected to earth ground The power supply input is 24 VDC The positive side of the power supply is connected to pin 3 and the negative side to pin 4 of the D sub connector Damage may occur to the circuitry if excessive voltage is applied polarity reversed or if a wrong connection is made If using analog output described in the Analog Output section the analog outpu...

Page 20: ...tact life Therefore an arc suppression network shown schematically below is recommended The values of the capacitance C and the resistance R can be calculated by the following equations C I2 1 x 107 R E Ia where C is in farads R is in ohms I is DC or Acpeak load current in amperes E is DC or Acpeak source voltage in volts a 1 50 E Note that Rmin 0 5 Ω and Cmin 1 0 x 10 9 F RELAY 2 N O RELAY 1 N C ...

Page 21: ...refore the MicroPirani readout depends on the gas type and concentration The MicroPirani is calibrated for Nitrogen gas and will read a higher pressure when exposed to atmospheric air The Hot Cathode sensor is based on measurement of gas ionization therefore the Hot Cathode readout also depends on the gas type and concentration ...

Page 22: ...a f e D t l u a f e D t l u a f e D t n e m a l i F e v i t c A 1 s s e r d d A 3 5 2 e t a R d u a B 0 0 6 9 r e w o P s a g e D f f O t n e r r u C n o i s s i m E o t u A t n i o P t e S l o r t n o C e l b a n E n O 3 2 1 t n i o P t e S e l b a n E f f O r e w o P t n e m a l i F f f O n o i t c e r r o C s a G 1 n o i t a r b i l a C e p y T s a G n e g o r t i N 3 2 1 s i s e r e t s y H r ...

Page 23: ...ssages to multiple devices attached to the same system For example use 255 to change the baud rate for all devices Query and Command Syntax Queries return current parameter settings commands change the parameter setting according to the value the user types in the command syntax Each query or command must begin with the attention character and end with the termination string FF Syntax required for...

Page 24: ...with an error is device address NAK NAK code FF Examples ACK response 253ACK9600 FF baud rate changed to 9600 NAK response 253NAK160 FF command had an error possibly a typo The following list provides descriptions of the NAK codes that may be returned Error NAK Code Unrecognized message 160 Invalid argument 169 Value out of range 172 Command query character invalid or 175 Control setpoint enabled ...

Page 25: ...tion on filaments Values 1 2 default 1 Query 001AF FF Query Response 001ACK2 FF Command 001AF 2 FF Command Response 001ACK2 FF If a different filament is selected while the filament is on the filament power will turn off If the control set point is enabled see ENC it will need to be disabled to turn the filament power back on e g 001AF 2 FF 001ENC OFF FF 001FP ON FF 001ENC ON FF Address AD The AD ...

Page 26: ...e 001ACKDAC2 FF Emission Current EC The EC command returns or sets the sensor s emission current to 100uA or Auto range 100uA above 1x10 4 and 1mA below 1x10 4 Torr Values 100UA and AUTO for commands 100UA 1MA AUTO and 100UA AUTO for responses default AUTO Query 001EC FF Query Response 001ACK1MA AUTO FF Command 001EC AUTO FF Command Response 001ACK100UA AUTO FF Factory Default FD The FD command se...

Page 27: ...TST FF Query Response 001ACKOFF FF Command 001TST ON FF Command Response 001ACKON FF Unit U The U command returns or sets the pressure unit to Torr mBar or Pascal The units affect all pressure measurements including set point values Values TORR MBAR PASCAL default TORR Query 001U FF Query Response 001ACKTORR FF Command 001U MBAR FF Command Response 001ACKMBAR FF UserTag UT The UT command returns o...

Page 28: ...d Degas Commands section Values ON OFF Query 001FS FF Query Response 001ACKON FF Firmware Version MicroPirani FV The FV command returns the MicroPirani firmware version Query 001FV FF Query Response 001ACK1 00 FF FirmwareVersion Hot Cathode FVHC The FVHC command returns the Hot Cathode firmware version Query 001FVHC FF Query Response 001ACK1 00 FF HardwareVersion MicroPirani HV The HV command retu...

Page 29: ...ce the sensor Values CLR Query 001TIM1 FF Query Response 001ACK000000024 FF Command 001TIM2 CLR FF Command Response 001ACKCLR FF Transducer Status T The T command returns the current status of the Hot Cathode Related commands Active Filament AF Set Up Commands section Set Point Value SP1 SP2 SP3 and Hysteresis Value SH1 SH2 SH3 Set Point Commands section Values F Filament fault filament cannot tur...

Page 30: ...he sensor s two filaments see Active Filament AF Set Up Commands section To query the ON OFF status of the filament use the Filament Status FS command or the Transducer Status T command Status Commands section NOTE This command works only when the control set point is disabled see Enable Set Point ENC in the Set Point Commands section Values ON OFF default OFF Command 001FP ON FF Command Response ...

Page 31: ...d C contacts will be closed The direction of the set point ABOVE or BELOW is configured using the Set Point Direction SD1 SD2 SD3 command next page The set point must be enabled for the set point command to function see the Enable Set Point EN1 EN2 EN3 command Values Two or three digit scientific notation default 1 00E0 Torr Query 001SP1 FF Query Response 001ACK1 00E 2 FF Command 001SP1 1 00E 3 FF...

Page 32: ...urns enable status or enables disables the set point relay Values ON OFF Query 001EN1 FF Query Response 001ACKOFF FF Command 001EN1 ON FF Command Response 001ACKON FF Enable Control Set Point ENC The ENC command allows the MicroPirani to turn the Hot Cathode on or off If the value is ON decreasing pressure turns the Hot Cathode on at 1x10 3 Torr and increasing pressure turns the Hot Cathode off at...

Page 33: ...or the MicroPirani Vent the transducer to atmospheric pressure before performing atmospheric calibration For best results leave the MicroPirani at the calibration pressure for at least 20 minutes before using the ATM command Values Pressure value in scientific notation Command 001ATM 7 60E 2 FF Command Response 001ACK7 60E 2 FF Vacuum Calibration VAC The VAC command zeroes the MicroPirani readout ...

Page 34: ...001GT FF Query Response 001ACKAIR FF Command 001GT NITROGEN FF Command Response 001ACKNITROGEN FF Gas Correction GC The GC command returns or sets the Hot Cathode gauge s sensitivity for use with gasses other than air or nitrogen For example if Argon is the system gas then the gas correction value would be 1 29 See the Gas Correction Factor Table for values Values 0 10 to 50 1 default 1 Query 001G...

Page 35: ...ntly higher than system pressure Degas is only activated if the indicated pressure is below 1x10 5 Torr Set points are active during degas When degas is turned on it is likely that the sensor pressure will increase to values exceeding 1x10 4 Torr When the indicated pressure exceeds 1x10 4 Torr degas turns off Degas automatically turns on again when the indicated pressure drops back below 1x10 4 To...

Page 36: ...ase of the Hot Cathode is 1 For example if using Argon gas in the system use the GC command as follows 253GC 1 29 FF Gas Correction Factor Table s a G l o b m y S n o i t c e r r o C s a G C G r o t c a F r i A 0 0 1 n o g r A r A 9 2 1 e d i x o i D n o b r a C O C 2 2 4 1 m u i r e t u e D 2 D 5 3 0 m u i l e H e H 8 1 0 n e g o r d y H H2 6 4 0 n o t p y r K r K 4 9 1 n o e N e N 0 3 0 n e g o ...

Page 37: ...ther ground The voltage drop from the supply current will produce errors in the analog output voltage The longer the cable the worse the error will be The graph below shows the correlation of DAC1 analog output to pressure To calculate pressure from voltage P Torr 10 2V 11 Analog Output DAC1 Voltage vs Pressure 0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 0 1 0E 10 1 0E 09 1 0E 08 1 0E 07 1 0E 06 1 0E 05...

Page 38: ...5 4 0E 02 4 80 1 0E 08 1 50 8 0E 02 4 95 2 0E 08 1 65 1 0E 01 5 00 4 0E 08 1 80 2 0E 01 5 15 8 0E 08 1 95 4 0E 01 5 30 1 0E 07 2 00 8 0E 01 5 45 2 0E 07 2 15 1 0E 00 5 50 4 0E 07 2 30 2 0E 00 5 65 8 0E 07 2 45 4 0E 00 5 80 1 0E 06 2 50 8 0E 00 5 95 2 0E 06 2 65 1 0E 01 6 00 4 0E 06 2 80 2 0E 01 6 15 8 0E 06 2 95 4 0E 01 6 30 1 0E 05 3 00 8 0E 01 6 45 2 0E 05 3 15 1 0E 02 6 50 4 0E 05 3 30 2 0E 02 ...

Page 39: ...00 4 00 5 00 6 00 7 00 8 00 9 00 10 00 1 0E 10 1 0E 09 1 0E 08 1 0E 07 1 0E 06 1 0E 05 1 0E 04 1 0E 03 1 0E 02 1 0E 01 1 0E 00 1 0E 01 1 0E 02 1 0E 03 Pressure mBar Volts To calculate Pressure from Voltage Where C 0 for mBar C 2 for Pascal C 0 125 forTorr P 10 V 7 75 75 C ...

Page 40: ... 2 7 2 7 0 E 0 2 5 0 E 0 2 7 0 E 5 1 5 1 5 4 7 1 0 E 0 4 1 0 E 0 4 1 0 E 0 3 5 1 5 9 2 7 0 E 0 4 5 0 E 0 4 7 0 E 0 3 3 7 7 6 7 1 0 E 0 8 1 0 E 0 8 1 0 E 0 6 3 7 7 1 3 7 0 E 0 8 5 0 E 0 8 7 0 E 0 6 0 0 5 7 7 0 0 E 0 1 2 0 E 0 1 1 0 E 5 7 0 0 5 2 3 6 0 E 0 1 4 0 E 0 1 7 0 E 5 7 8 5 7 9 7 0 0 E 0 2 2 0 E 0 2 0 0 E 5 1 8 5 7 4 3 6 0 E 0 2 4 0 E 0 2 6 0 E 5 1 5 1 0 2 8 0 0 E 0 4 2 0 E 0 4 0 0 E 0 3 5 1...

Page 41: ...reas with a gas that is different from that of the system gas Helium is suitable for probing a system pumping air or nitrogen 1 Pump your vacuum system to a base pressure 2 Slowly and methodically probe with a small amount of the tracer gas helium 3 Note the pressure reading The pressure will rise or fall depending upon the thermal conductivity of the probe gas relative to the system gas The large...

Page 42: ... metal seal flange CF or with a Viton seal flange KF To bake out the sensor first remove the electronics To do this 1 Disconnect the cable from the 979 2 Remove the four screws as shown in the figure on the next page The screws may be difficult to access when the sensor is attached to the vacuum system 3 Pull the metal housing and the electronics from the sensor The bottom panel remains attached t...

Page 43: ...he Time On TIM1 TIM2 command described in the Status Commands section to clear the filament time To disassemble the electronics for sensor replacement use the procedure in the Bakeout section To re assemble the electronics use the disassembly steps in reverse order For sensor part numbers see the Accessories and Part Replacement section 6 55 3934 0 3 3 2 34 9 3934 8 42 3 352 2 2 6 2 54 ...

Page 44: ...o o t e h t h t i w e p y t s a g e g n a h c t c e r r o c n i s i e p y t s a G T G n o i t a r b i l a C e p y T s a G d n a m m o c n o i t a r b i l a c n a p s t s u j d a t c e r r o c n i s i n o i t a r b i l a C e h t g n i s u M T A n o i t a r b i l a C c i r e h p s o m t A d n a m m o c p i r t t o n s e o d t n i o p t e S d e l b a n e t o n t n i o p t e S r e p o r p o t t e s t ...

Page 45: ... D 0 1 x 1 e v o b a e r u s s e r p m e t s y S 5 n e h w r r o T t n e s s i d n a m m o c s a g e d Cleaning the 979 ATV Transducer Case and Sensor Tube The finish of the 979 ATV Transducer case is designed to resist many laboratory solvents clean the case with water or alcohol Take care to prevent a liquid from entering the electronic enclosure Roughing pump oils and other fluids condensing or...

Page 46: ...LOCATOR KEY SLOT F2 Sensor Test Resistance Values Table Pin Resistance Filament 1 or 2 to same filament 2 Ω Grid to grid 1 Ω Grid to collector or either filament 20M Ω Any pin to the sensor body 20M Ω The figure below shows the locations of the pins ...

Page 47: ...cessories and Part Replacement Description Part Number Sensor with 2 75 CF K97921 Sensor with 1 33 CF K97911 Sensor with NW40 KF K97951 Sensor with NW25 KF K97941 Sensor with NW16 KF K97931 Operation and Maintenance Manual 100014438 ...

Page 48: ...48 Series 979 ATVTransducer Notes ...

Page 49: ... energy of the ionizing electrons typically about 150 eV and the ionization probabilities of the constituent gases The total amount of ionization is related to the molecular concentration The ions are accelerated to a collector electrode where they create a current collector current in a circuit which includes an electrometer The measured current is proportional to the gas density which in turn is...

Page 50: ...om a hot wire to measure pressure End loss and radiation loss act as error signals and determine the low pressure limit of the sensor Optimizing operational parameters of the wire length and diameter thermal emissivity thermal conductivity and wire temperature can decrease end loss and radiation errors A standard Pirani sensor usually has a lower reading limit of about 10 3 Torr due to signal lost...

Page 51: ...ate A solid state MicroPirani sensor has several advantages over a wire based Pirani sensor The operational parameters are controlled and optimized to decrease the end loss and radiation errors the integrated temperature sensors improve the temperature compensation performance and the small geometry decreases the thermal lag time ensuring faster response time These improvements allow the MicroPira...

Page 52: ...52 Series 979 ATVTransducer ...

Page 53: ...Series 979 ATVTransducer ...

Page 54: ...Series 979 ATVTransducer ...

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