Visit our website at: www.mksinst.com Warranty Information MKS Instruments, Inc. provides an eighteen (18) month warranty from the date of shipment for new MKS products. The MKS Instruments, Inc. general terms and conditions of sale provide the complete and exclusive warranty for MKS products. This document is located on our web site at www.mksinst.com, or may be obtained by a contacting an MKS customer service representative.
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Attention: Calls attention to important procedures, practices or conditions. General safety information The safety instructions should always be followed during installation and operation of the 902B Absolute Piezo transducer. Pass safety information to all users. Safety Precautions: Electrical connections. The 902B must be properly electrically connected in order to perform according to the specifications.
Short form manual (15 pin version)/Short form manual (9 pin version) 100017096 Documentation & Software DVD If any items are missing, contact MKS Customer Service at +1-833-986-1686 or your local MKS sales office or distributor. Part number The 902B Absolute Piezo part number system has 5 digits that identify flange, communication interface, analog output type, I/O connector and sensor sealing type.
Description The 902B Absolute Piezo vacuum transducer offers a wide measuring range from 0.1 to 1000 Torr and is based on measurement of thermal conductivity and measurement of mechanical deflection of a silicon membrane. The 902B can be used in a variety of applications as a standalone unit or with the PDR900 display and controller unit.
4. 3 × GREEN flash User Adjustment executed successfully 5. 3 × RED flash User Adjustment failed 6. 2 sec. RED User switch disabled 7. RED Transducer defect 8. OFF Firmware upgrade mode (see page 48) or Power off 902B Abs Piezo Operation manual...
If the 902B transducer is located close to a gas source connection like a flow controller or leak valve the transducer pressure measurement can be higher than the actual chamber pressure. Location close to a pumping system connection can cause a lower pressure measurement than actual chamber pressure.
Transducer installation (electrical) The 902B is available with different input/output connectors. Use a cable with strain relief to ensure proper electrical connection and to reduce stress on the connectors. Ensure a low impedance electrical connection between the 902B transducer body and the ...
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To comply with EN61326-1 immunity requirements, use a braided shielded cable. Connect the braid to the metal hoods at both ends of the cable with the end for power supply connected to earth ground. 902B I/O Connector (15 pin) PIN Description...
At high communication baud rates and when using long cable runs, a termination resistor of typical 120 Ohm should be connected between pin 1 and 2 at the 902B DSUB connector and between pin A and B at the data communication equipment.
Communication Protocol The 902B transducer command set allows the user to change transducer parameters and receive pressure measurements. Settings and parameters like set point values, set point configurations and calibration data are stored in the transducers non-volatile memory. Communication software Communication software is required to communicate from a PC via RS232/485 interface to the transducer.
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Baud rate The baud rate represents the communication speed. The 902B supports 4800, 9600, 19200, 38400, 57600, 115200 and 230400 baud rates. The transducer is always delivered with 9600 bps factory default baud rate. Change of Baud rate: Command: @253BR!19200;FF...
Setpoint relays The 902B can be ordered with either 0, 1 or 3 mechanical relays that can be used for controlling external process equipment. Each relay has closing and breaking contacts and the contacts are rated 30 VDC, 1A resistive load. If the transducer is supplied without setpoint relays, the setpoint commands can still be accessed.
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The 902B transducer has an auto hysteresis setting of 10% of the set point value that overwrites the current hysteresis value whenever the set point value or set point direction is changed. If other hysteresis value than 10% is required, first set the set point value and set point direction before setting hysteresis value.
Factory default: Integrated Touch Display For 902B transducer versions with integrated touch display it is possible to see information about setpoints, sensors, model, and measurements unit. A pressure threshold alarm can be set and for transmitters with multiple sensors, it is possible to choose which sensor pressure value is displayed on the screen. All of this...
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Main screen. The following table shows the different menus and options available: Display-screen Information Start-up MKS logo and transducer model Home The Home screen shows the current pressure, the transducer model, the status of the setpoints, the triggering direction of each setpoint and shows if an alarm is enabled.
Pressure output The 902B transducer can provide pressure measurement output as an analog voltage or RS232/RS485 digital value. The digital value is presented as fractional number for PR1, PR2 and PR3 reading and as scientific number in PR4 reading. Pressure request: Query: @253PR2?;FF...
Accuracy and repeatability The 902B measuring accuracy is specified as transducer reading ± a percentage of the actual pressure. The basic measuring accuracy is factory calibrated and cannot be user adjusted. The repeatability specification is the transducers ability to repeat the same measurement value after multiple pressure cycles.
AO1! × Analog out 2: AO2! × (1) If the transducer is delivered with other analog output than standard mks (part number specified), then the factory default value will be specified by the specials part number. Calibration setup: Description Command...
The 902B transducer can be delivered with factory locked tamperproof settings for safety interlock applications. This option is defined in the special settings. If delivered with factory lock the transducer settings can only by changed by return of gauge to MKS.
Query: @253TEM?;FF Query reply: @253ACK25;FF Transducer Status - T The T command returns the MicroPirani sensor status as O for OK, M for MicroPirani fail or Z for Piezo fail. Query: @253T?;FF Query reply: @253ACKO;FF 902B Abs Piezo Operation manual...
Analog output The 902B transducer provides a voltage output as function of pressure. The 902B is available with a selection of factory configured outputs determined by the part numbers listed below. The default analog output calibration is “14” corresponding to the Linear10 functions stated below for the units: torr, mbar and pascal.
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Analog output setup The 902B can emulate analog voltage outputs from other vacuum transducers. The 902B analog output can be assigned to the absolute Piezo sensor. The parameter digit represents the analog output calibration. The primary analog output provides 16 bit resolution.
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Dual analog output The 902B is available with dual analog output which can be used to provide an alternative output for amplification of range or to emulate another transducer type while still using the MKS standard output. This feature is a hardware option and must be specially ordered. Refer to part number specifications page 3.
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Analog output calibration = 4 (MKS standard 1 VDC/decade) The standard MKS analog output provides always 1VDC/decade. If the transducer pressure unit is changed from Torr to Pascal or mbar the analog output scaling will change as well, so it represents 1VDC/decade Torr or 1VDC/decade mbar or Pa.
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Analog output calibration = 7 (MKS GP275 emulation) The GP275 emulation provides a strongly non-linear output with very poor resolution in the low range and close to atmospheric pressure. Torr mbar Pascal 1.00E-05 1.33E-05 1.33E-03 0.372 1.00E-04 1.33E-04 1.33E-02 0.372 2.50E-04...
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1.07E+05 3.2398 Analog out calibration = 9 (MKS Moducell 325, amplified three times) The Moducell x3 emulation is in curve form identical with the standard Moducell, however, to provide better signal resolution the signal is amplified by a factor of three.
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Analog output calibration = 10 (MKS Baratron 0.1 Torr) The 0.1 Torr Baratron emulation provides a signal directly proportional with pressure with a full scale reading of 10 VDC at 0.1 Torr. Torr mbar Pascal 1.00E-3 1.33E-3 1.33E-1 0.100 5.00E-3 6.66E-3...
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100.0 133.3 1.333E+4 10.000 Analog output calibration = 14 (MKS Baratron 1000 Torr, 902B Linear10) The 1000 Torr Baratron emulation provides a signal directly proportional with pressure with a full scale reading of 10 VDC at 1000 Torr. Torr mbar Pascal 10.0...
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Analog output calibration = 23 (MKS GP275 Emulation 9 VDC FS) The GP275 emulation with 9VDC full scale provides a strongly non linear output with very poor resolution in the low range and close to atmospheric pressure. Torr mbar Pascal 1.00E-03...
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1.00E+03 1.00E+05 9.99 Analog output calibration = 25 (MKS GP275 Emulation 5.6 VDC FS) The GP275 emulation with 5.6VDC full scale provides a strongly non linear output with very poor resolution in the low range and close to atmospheric pressure.
@xxxSD3?;FF below relay will be energized below setpoint value @xxxSPD?;FF @xxxACKON;FF Setpoint safety delay Transducer information Command Response Explanation @xxxMD?;FF @xxxACK902B;FF Model number (902B) @xxxDT?;FF @xxxACKPiezo;FF Device type name (Piezo) @xxxMF?;FF @xxxACKMKS;FF Manufacturer name (MKS) @xxxHV?;FF @xxxACKA;FF Hardware version @xxxFV?;FF @xxxACK1.00;FF...
Set analog voltage output 2 calibration Information setup Command Response Explanation @xxxUT!PIEZOABS;FF @xxxACKPIEZOABS;FF Set transducer user tag User Switch Command Response Explanation @xxxSW!ON;FF @xxxACKON;FF Enable / disable user switch = Transducer communication address (001 to 253. Broadcast addresses: 254, 255) 902B Abs Piezo Operation manual...
Firmware upgrades (RS232 only) The 902B firmware can be upgraded by the user. The following procedure should be used: 1. Install the 900 Series firmware download software from the Documentation CD or download from www.mksinst.com/vtsw/ 2. Turn power off 3. Hold down the User switch while turning power on 4.
Q: Is it necessary to use the ground wire between RS485 communication equipment and transducer? A: Yes - both RS232 and RS485 communication requires a 3 wire connection between transducer and communication equipment. Measurement, Calibration and adjustment 902B Abs Piezo Operation manual...
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Q: Reverse voltage has been connected to power supply input. Is the transducer damaged? A: Not likely – the transducer power supply circuit has reverse voltage and over voltage protection however. MKS cannot guarantee that the transducer will not be damaged. Q: If contaminated, can the transducer sensor element be cleaned? A: Yes –...
Check part number to see if transducer has setpoint relays No analog output Power supply turned off Check electrical connections Status LED illuminating red Sensor element defect - Refer to Service and Repair page 52 902B Abs Piezo Operation manual...
Maximum pressure: 1500 Torr Supply Voltage: 9-30 VDC Power consumption: <1.2 watt Fuse (thermal recoverable): 200 mA Analog output (MKS standard): 0-10 VDC Analog output 1 resolution: 16 bit Analog output 2 resolution: 12 bit Analog output impedance: 100 Ω...
PDR900-12-JP PDR900 Controller JP power cable. mbar / pascal unit PDR900-12-DK PDR900 Controller Danish power cable PDR900 Transducer Cables for 902B (15 pin HD DSUB) For transducer part number: 902B-x1x2x. 902B-x1x3x. 902B-x1x5x Part number Description Interface 100013620 3 m (10ft.)
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• Data logger tool for data analysing See m or e on : w ww .m k s i n st. co m /p d r 90 0 902B Absolute Piezo transducer with integrated display • Display of real time pressure measurements • Clear backlight display •...
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