MKS HPS 903 Series User manual

Inverted MagnetronTransducer
(IMT)
ColdCathodeIonization
VacuumSensor
OPERATION AND
MAINTENANCE MANUAL
HPSTM Products Series 903

Please Note:
MKS Instruments provides these documents as the latest version for the revision indicated.
The material is subject to change without notice, and should be verified if used in a critical
application.

Cold Cathode Ionization Vacuum Sensor
HPSTM Products Series 903
Inverted MagnetronTransducer
(IMT)
ColdCathodeIonization
VacuumSensor
JUNE 1999
PART #1090300 REV. A

Cold Cathode Ionization Vacuum Sensor
Part#1090300XX
__ __
Serial # __ __ __ __ __ __
Please fill in these numbers and
havethemreadilyavailablewhencalling
forserviceoradditionalinformation.
(The part number can be found on
your packing slip, and both the part
numberandserialnumberarelocatedon
the bottom side of the housing.)
© 1999 MKS Instruments, Inc. HPSTM Products, Inc., All rights reserved.
ALCONOXisaregisteredtrademarkofAlconox,Inc.
IgniTorrisatrademarkofMKSInstruments,Inc.,HPSTM Products,Inc.
InconelisaregisteredtrademarkofIncoAlloysInternational,Inc.
Scotch-Briteisatrademarkof3M.
IsaregisteredtrademarkofMKSInstruments,Inc.,HPSTM Products,Inc.
For more information or literature, contact:
MKS Instruments, Inc., HPSTM Products, Inc.
5330 Sterling Drive
Boulder, CO 80301 USA
Phone: [phone]
800-345-1967
FAX: [phone]

Cold Cathode Ionization Vacuum Sensor
Table of Contents
Table of Contents
Package Contents ..................................................................... 1
Symbols Used in this Manual.................................................... 1
Safety Precautions .................................................................... 2
Specifications............................................................................ 3
Feature and Control Locations .................................................. 5
Typical Applications for the Series 903 (IMT) ............................ 6
About the HPSTM Products Series 903 (IMT) ............................. 7
Installing the Series 903 (IMT)................................................... 8
Location .................................................................................................... 8
Orientation ................................................................................................ 8
Contamination........................................................................................... 8
VacuumConnection .................................................................................. 9
ElectricalConnection ................................................................................ 9
Input/OutputWiring ................................................................................... 9
RelayInductive LoadsandArc Suppression ........................................... 11
Operating the Series 903 (IMT) ............................................... 12
Starting the (IMT) ................................................................................... 12
ReadingPressure ................................................................................... 12
Equation for ConvertingVoltage to Pressure ........................................... 13
Using the Set Point ................................................................................. 13
Ventingto Atmosphere............................................................................ 14
Analog-to-Digital(A/D)Converter ............................................................ 14
PreparingforBakeout ............................................................................. 14
LeakDetection........................................................................................ 14
Using the Series 903 (IMT) with Other Gases ......................... 16
CalibratingforOther Gases..................................................................... 17
Maintaining the Series 903 (IMT) ............................................ 18
Troubleshootingand Service ................................................................... 18
Contaminationof the (IMT)Sensor ......................................................... 19
Disassembly .................................................................................................................. 19
Cleaning.......................................................................................................................... 19
Assembly........................................................................................................................ 20

Cold Cathode Ionization Vacuum Sensor
Accessories/Part Replacement ............................................... 22
ProductWarranty ..................................................................... 23
Notes....................................................................................... 24
Appendix A:How the Series 903 (IMT) Works........................ A.1
Theoryof a ColdCathode Ionization Sensor ..........................................A.1
Notes......................................................................................A.3

1
Cold Cathode Ionization Vacuum Sensor
BeforeunpackingyourSeries903InvertedMagnetronTransducer(IMT)
Vacuum Sensor, check all surfaces of the packing material for shipping
damage.
Please be sure that your Series 903 (IMT) package contains these items:
1(IMT)unit (integrated sensortube and electronics)
1female,9-pinsubminiatureD(D-sub)connector
1 Series903InvertedMagnetronTransducer(IMT)Cold
CathodeIonizationVacuumSensor User'sManual.
If any items are missing from the package, call HPSTM Products
CustomerServiceat1-303-449-9861or1-800-345-1967.
Inspect the (IMT) for visible evidence of damage. If it has been damaged in
shipping, notify the carrier immediately. Keep all shipping materials and
packaging for claim verification. Do not return the product to HPSTM.
Package Contents
t
t
t
Symbols Used in this Manual
The first two symbols below, that may be located on your Series 903 (IMT),
identify critical safety concerns. They are used throughout this manual to
further define the safety concerns associated with the product.
The last two symbols identify other information in this manual that is
essential or useful in achieving optimal performance from the (IMT).
CAUTION: Risk of electrical shock.
CAUTION: Refertomanual.
Failure to heed message could result in personal injury or
serious damage to the equipment or both.
Failure to heed message could result in damage to the
equipment.
Calls attention to important procedures, practices, or
conditions.
(

2Cold Cathode Ionization Vacuum Sensor
Install the (IMT) only on a grounded vacuum system.
When using an (IMT) with a flange and an elastomer seal, use an all-metal
clamp to ensure electrical continuity between the( IMT) and the grounded
vacuum system.
When using an ( IMT) with a 1-inch tube, use a ground strap to connect the
sensor to the grounded vacuum system.
Do not connect power to the (IMT) unless its flange is attached to
thevacuum system andtheelectronics assembly isfastened to
thesensorhousing.
Do not exceed voltage requirements as this may damage the electronics
assembly. Refer to the information on page 9 for proper connection
instructions.
The (IMT) may be connected only to devices conforming to
therequirements ofasecondary extralowvoltage inaccordance
withEN61010-1.
Allow only qualified technicians to service the (IMT).
Users should not remove covers, casings, or plug-in components. Injury may
result. Turn off power to the (IMT) before proceeding with maintenance. Only
aqualified technician should replace oradjust electronic components.
As much as 4 kV may be present in the (IMT) during operation. The current is
limited to 100 mA.
The Series 903 (IMT) must be used as instructed by MKS Instruments,
Inc., HPSTM Products Inc., for safe operation. Using or modifying the
equipmentinconsistentwithspecificationsmayrendertheproduct's
inherentprotectionuseless.
Safety Precautions

3
Cold Cathode Ionization Vacuum Sensor
Specifications
MeasuringRange 3.0 x 10-10 to 5.0 x 10-3 Torr
3.9 x 10-10 to 6.5 x 10-3 mbar
3.9 x 10-8 to 6.5 x 10-1 Pa
Set Point Range 1.0 x 10-9 to 1.0 x 10-3 Torr
1.3 x 10-9 to 1.3 x 10-3 mbar
1.3 x 10-7 to 1.3 x 10-1 Pa
Repeatability Approximately±5%
CalibrationGas Air/nitrogen
OperatingTemperatureRange 0°to50°C(32° to 122°F)
BakeoutTemperature 400°C(752°F)maximumforCF
flangedunit; without electronics,
cable,or magnet
RelativeHumidity 80%maximumfor temperatures
lessthan31°C,decreasinglinearly
to 50% maximum at 40°C
Altitude 2000m (6561 ft) maximum
Insulation PollutionDegree2
Controls 1 relay set point
RelayContactRating SPDT, 1 A @ 30 VDC, resistive
RelayHysteresis 150mV*
RelayResponse < 50 msec (0 to 99%)
for DP from 5.0 x 10-8 Torr to
3.0 x 10-4 Torr
PowerRequirement 14 to 30 VDC, 150 mA maximum
Output Voltage 1.5 to 8.7 VDC, linear output,
30Wmaximum outputimpedance
OutputLoad 100kWnominal
10kWminimum
*150 mV is equivalent to a change in pressure of 1.41 (or 100.150) times the set
point, e.g., if the relay is set to activate at 2.0 x 10-6 Torr (5.301 V), it will
deactivate at 2.82 x 10-6 Torr (5.451 V).

4Cold Cathode Ionization Vacuum Sensor
Design and/or specifications subject to change without notice.
InternalOperatingVoltage 4 kV maximum
current limited to 133 mA
InstallationOrientation Any
Internal Volume 0.9 in.3(15.0 cm3) maximum
MaterialsExposed to Vacuum SS 304, SS 302, aluminum, glass,
Inconel®X-750,aluminaceramic
Display LED indicators for set point (red),
highvoltage(yellow),andpower
(green)
ElectronicCasing ABS plastic, UL 94-5V flame rating
(withconductivecoating)
CasingDimensions 5" x 3" x 4.2"
(W x D x H) (127 mm x 76 mm x 108 mm)
TypicalWeight(with CF Flange) 2.3 lb (1.04 kg)
VacuumConnection KF 25
KF 40
2¾"CF(rotatable)
1" tubing
CECertification EMC Directive
GeneralProductSafety Directive