TELEVAC MX7B, Instruction Manual

Page 1: ...47 2500 mx7b_im rev E Page 1 of 23 MX7B Cold Cathode Ionization Gauge Instruction Manual Rev E 2022 Televac The Fredericks Company 2400 Philmont Avenue Huntingdon Valley PA 19006 web www frederickscompany com email sales frederickscompany com tel 1 215 947 2500 fax 1 215 947 7464 ...

Page 2: ...ng the High Voltage On and Off 7 5 Menu Navigation 8 5 1 Description 8 5 2 Menu Structure 9 6 Explanation of Menu Items and Navigation 10 6 1 Measurement 10 6 2 High Voltage Toggle 10 6 3 System Settings 10 6 4 Calibration 12 6 5 Set Points 13 6 6 Output 13 7 Analog Output 14 7 1 Description 14 7 2 Linear 14 7 3 Linear by Decade 14 7 4 Logarithmic 15 8 Cleaning the MX7B Sensor 16 8 1 Cleaning Inst...

Page 3: ...be changed through RS 485 communications with a PC through USB communications with a PC or through the unit s front panel using four capacitive touch buttons located on the top of the unit The MX7B has 2 set points one relay and one open collector and a selectable analog output option The analog output is a configurable 0 10 V output that includes options for linear linear by decade and logarithmi...

Page 4: ... 2022 Televac The Fredericks Company www televac com sales televac com 1 215 947 2500 mx7b_im rev E Page 4 of 23 1 4 Dimensions ...

Page 5: ...use of the instrument Televac disclaims all liability for the customer s failure to comply with these requirements 2 1 3 1 READ Instructions Read all safety and operating instructions before operating the product 2 1 3 2 RETAIN instructions Retain the safety and operating instructions for future reference 2 1 3 3 HEED warnings Adhere to all warnings on the product and in the operating instructions...

Page 6: ...ety Instructions 3 2 1 Review all safety instructions outlined in Section 2 3 3 Connect Power 3 3 1 Connect a 24V power supply to the unit See the pin out in Section 4 2 for more information 3 4 Check the Measurement Screen 3 4 1 The unit should power up and display OFF on the measurement screen Do not attempt to turn on the high voltage 3 5 Power down the MX7B 3 5 1 Power down the MX7B and instal...

Page 7: ...fe of the unit Exposure to oils and other contaminants will decrease the accuracy and decrease the life of the sensor Do not expose the unit to corrosive gases 4 2 Electrical Information 4 2 1 Power connectors and adapters for use with the MX7B are available for purchase from Televac Operators wishing to create their own adapters should refer to the pin out of the MX7B below Each connection labele...

Page 8: ...Televac MX2A or MX4A to automatically control the unit via an open collector or relay For more information see Application Note AN 3023 4 3 5 To protect the sensor from damage if the sensor high voltage is toggled on when in either Menu Control or Pin Control mode the pressure is above 1 10 3 Torr overcurrent protection will turn the sensor off If the sensor is in Menu Control mode then a command ...

Page 9: ...w Resolution 5 2 3 3 2 High Resolution 5 2 3 4 Vsense Control 5 2 3 4 1 Menu Control 5 2 3 4 2 Pin Control 5 2 3 5 Diagnostics 5 2 3 5 1 FW Date 5 2 3 5 2 FW Version 5 2 4 Calibration 5 2 4 1 1 10 6 Torr 5 2 4 2 1 10 5 Torr 5 2 4 3 1 10 4 Torr 5 2 4 4 1 10 3 Torr 5 2 4 5 Analog Output Adjustment 5 2 5 Set Points 5 2 5 1 SP1 Off 5 2 5 2 SP1 On 5 2 5 3 SP2 Off 5 2 5 4 SP2 On 5 2 6 Output 5 2 6 1 Lin...

Page 10: ... Control Mode then the user must turn on the high voltage by sending a command over communications or by navigating to the High Voltage Toggle menu screen Once at the High Voltage Toggle screen press ENT to unlock the screen press UP or DOWN to change the setting and then press ENT to save the change The high voltage will then turn on and a pressure indication will be displayed on the Measurement ...

Page 11: ...ure reading Gas Type Conversion Factor Nitrogen 1 00 Hydrogen 3 00 Helium 8 90 Neon 4 30 Argon 0 84 Krypton 0 59 Carbon Dioxide 0 69 6 3 4 Resolution 6 3 4 1 The MX7B displays two significant digits by default low resolution The user may choose to operate the gauge in high resolution mode in which the unit will display three significant digits 6 3 5 High Voltage Control 6 3 5 1 The MX7B has an upp...

Page 12: ...hanging calibration settings voids NIST Traceable calibrations 6 4 4 10 6 Torr 6 4 4 1 The 1 10 6 calibration point allows the gauge to adjust the pressure reading at 1 10 6 Torr This calibration point should not be used to adjust the gauge reading below a reference pressure of 5 10 7 Torr or above 5 10 6 Torr 6 4 5 10 5 Torr 6 4 5 1 The 1 10 5 calibration point allows the gauge to adjust the pres...

Page 13: ...ired reading is reached press ENT to save the change or SEL to navigate away without saving the change 6 6 Output 6 6 1 The MX7B provides a user selectable analog output as well as RS 485 and USB digital outputs 6 6 2 To modify the output settings 6 6 2 1 Navigate to the measurement screen 6 6 2 2 Press SEL five times 6 6 2 3 Press UP and DOWN to navigate between the analog output and RS 485 scree...

Page 14: ...wable but not settable Use the high value 1 0 10H exponent H in the following equation to convert the voltage output to pressure 𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉 𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂 10𝐻𝐻 1 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 7 2 2 To select the Linear output navigate to the Analog Output screen press ENT and then use the UP or DOWN arrow to select Linear Press ENT to save the change Then press DOWN once to navigate to the Output High screen...

Page 15: ...𝑂𝑂𝑂𝑂𝑂𝑂𝑂 0 𝐿𝐿 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 10 𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉 𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜𝑜 7 4 2 For example with the logarithmic range set to a 0 V value of 1 10 7 and a 10 V value of 1 10 3 and a voltage reading of 3 075 Volts the pressure corresponds to 𝑆𝑆𝑆𝑆𝑆𝑆𝑆𝑆 10 3 7 2 5 𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂𝑂 0 7 7 𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 10 3 075 2 5 7 1 7 10 6 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 7 4 3 To select the Logarithmic output navigate to the Analog O...

Page 16: ...t and the anode assembly should be replaced See below for relevant part numbers 8 1 7 Blast the vacuum wetted portions of the body with glass beads labeled with blue in the diagram concentrating on the pole piece and O ring areas but making sure to clean all surfaces wetted to vacuum If the threaded end of the tube needs to be cleaned it can be bead blasted as well 8 1 8 After cleaning use compres...

Page 17: ...Communications Specifications heading for information on what settings are necessary to properly communicate with the MX7B 9 2 Changing Communications Settings 9 2 1 The communication parameters baud rate address etc are changed through the local menu Please see Section 6 in this manual entitled Explanation of Menu Items and Navigation for more information on navigating and editing within the menu...

Page 18: ...d Response Description R1 xx Read units where xx is PA Pa TR Torr MB mbar R3 xx Read resolution where xx is LO low HI high R5 xyzzabb Read analog output range where x 1 linear 2 log 3 linear by decade y high value exponent sign zz high value exponent a low value exponent sign bb low value exponent R6 xx Read gas type where xx is N2 Nitrogen H2 Hydrogen NE Neon C2 Carbon Dioxide AR Argon HE Helium ...

Page 19: ...thmic yzz high value abb low value y high value exponent sign zz high value exponent a low value exponent sign bb low value exponent W53 3 Set analog output format to linear by decade W6xx xx Set gas type where xx is N2 Nitrogen AR Argon H2 Hydrogen HE Helium NE Neon KR Krypton C2 Carbon Dioxide Response is new gas type W7YppsePPSE ppseePPSEE Set thresholds for set point Y where ppsee SPL PPSEE SP...

Page 20: ...mic yzz high value abb low value y high value exponent sign zz high value exponent a low value exponent sign bb low value exponent W53 3 Set analog output format to linear by decade W6xx xx Set gas type where xx is N2 Nitrogen AR Argon H2 Hydrogen HE Helium NE Neon KR Krypton C2 Carbon Dioxide Response is new gas type W7YppsePPSE ppseePPSEE Set thresholds for set point Y where ppsee SPL PPSEE SPH ...

Page 21: ...ion adjustment response is new pressure reading WC3xyy ppsee Set 1E 4 calibration adjustment response is new pressure reading WC4xyy ppsee Set 1E 3 calibration adjustment response is new pressure reading WC5xyy ppsee Write analog output adjustment Return value is pressure reading 9 4 6 USB Commands for Setting RS 485 Communications Settings Command Response Description C1 xxxx Return serial baud r...

Page 22: ...EE 1E 4 Torr Adjustment is Baaa reading is PPSEE 0WC4Baaa CR PPSEE 1E 3 Torr Adjustment is Baaa reading is PPSEE 9 6 USB Sample Commands 9 6 1 Note that all USB commands are the same as the RS 485 commands with the star and address prefix omitted Command Output Description R1 CR 0001 Units are in Pa 0002 Units in Torr 0003 Units in mbar R2 CR ppseePPSEE Lower set point 1 given by ppsee Upper set p...

Page 23: ...lf Command error an invalid character was sent for the command or an invalid number after the character 0N0002 cr lf Units error an invalid parameter was sent after a command specifier 9 8 Firmware Updates 9 8 1 The MX7B has the ability to update the firmware when in the field over the USB communications For more information on updating the firmware please contact sales frederickscompany com ...