MKS 937B Series User manual

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MKS 937B Operation Manual 2
Table of Contents
Package Contents.................................................................................................................................. 7
1 Safety Information ..................................................................................................................... 8
1.1 Symbols Used in this Manual and their definitions ......................................................... 8
1.2 Safety Precautions .......................................................................................................... 8
1.2.1 Safety Procedures and Precautions ............................................................................ 8
2 Specifications .......................................................................................................................... 10
2.1 Controller....................................................................................................................... 10
2.2 Sensors ......................................................................................................................... 12
2.3 Controller Display Messages ........................................................................................ 16
3 Feature, Control Locations and Dimensions........................................................................... 17
4 Typical Applications for the Series 937B Controller................................................................ 19
5 HPSProducts Series 937B Multi-Sensor High Vacuum System.......................................... 20
6 Operating the Series 937B Controller ..................................................................................... 22
6.1 Power ............................................................................................................................ 22
6.2 Front Panel Control Lock............................................................................................... 22
6.3 Front Panel Display ....................................................................................................... 22
6.3.1 Standard front panel display ...................................................................................... 22
6.3.2 Large font displays..................................................................................................... 23
6.4 System Setup ................................................................................................................ 24
6.4.1 Overview of 937B System setup................................................................................ 24
6.4.2 Display system setup parameters.............................................................................. 25
6.4.3 Change and save a parameter value......................................................................... 25
6.4.4 Description of the system setup parameters ............................................................. 26
6.5 Channel Setup for Pressure Measurement................................................................... 30
6.5.1 Overview of 937B Channel setup .............................................................................. 30
6.5.2 Setup for a Capacitance Manometer ......................................................................... 32
6.5.3 Setup for a PR (Pirani)/CP (convection Pirani) sensor .............................................. 34
6.5.4 Setup a Cold Cathode Sensor ................................................................................... 37
6.5.5 Setup a Hot Cathode Sensor ..................................................................................... 40
6.6 Power Control of a Pressure Sensor............................................................................. 43
6.6.1 Power (including degas) control of a sensor using front panel control button........... 43
6.6.2 Power (including degas) control of a sensor via 37 pin AIO Dsub connector ........... 44
6.6.3 Power (including degas) control of a sensor using Serial communication commands.45
6.7 Leak Test Using the 937B Controller ............................................................................ 45
6.7.1 Leak test principle applied for the 937B..................................................................... 45
6.7.2 Procedures for a leak test with the 937B ................................................................... 46
7 Installing Vacuum Sensors ..................................................................................................... 48
7.1 Installing cold cathode sensors ..................................................................................... 48
7.1.1 Locating a Cold Cathode Sensor ............................................................................... 48
7.1.2 Orienting a Cold Cathode Sensor .............................................................................. 48
7.1.3 Managing Contamination in a Cold Cathode Sensor................................................. 48
7.1.4 Connecting the Series 421/422 Sensor ..................................................................... 48
7.1.5 Connecting the 423 I-MAG Sensor............................................................................ 49

MKS 937B Operation Manual 3
7.2 Installing hot cathode sensors....................................................................................... 49
7.2.1 Locating a Hot Cathode Sensor................................................................................. 49
7.2.2 Preventing Contamination in a Hot Cathode Sensor ................................................. 49
7.2.3 Orienting a hot cathode sensor.................................................................................. 49
7.2.4 Connecting a Hot Cathode Sensor to the vacuum system........................................ 49
7.2.5 Connecting a Hot Cathode Sensor to the 937B Controller ........................................ 50
7.3 Installing Pirani Sensors................................................................................................ 52
7.3.1 Locating a Pirani Sensor............................................................................................ 52
7.3.2 Preventing Contamination in a Pirani Sensor ............................................................ 52
7.3.3 Orienting the Series 317 Pirani Sensor...................................................................... 52
7.3.4 Orienting the Series 345 Pirani Sensor...................................................................... 52
7.3.5 Connecting the Series 317/345 Sensors ................................................................... 52
7.3.6 Preparing the 317 Sensor for Bakeout....................................................................... 54
7.4 Capacitance Manometers - MKS Baratron ................................................................... 54
7.4.1 Installing a Baratron Capacitance Manometer........................................................... 54
7.4.2 Connecting a Baratron™ Capacitance Manometer ................................................... 54
8 Connecting Relay and Analog Outputs................................................................................... 56
8.1 Connecting 937B relay outputs ..................................................................................... 56
8.1.1 Pin out for the 937B relay output ............................................................................... 56
8.1.2 Proper setting of a relay............................................................................................. 57
8.1.3 Relay Inductive Loads and Arc Suppression ............................................................. 58
8.2 Connecting the 937B Analog Output............................................................................. 58
8.3 Buffered analog output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 9
8.4 Logarithmic/Linear and combination analog output ...................................................... 69
8.4.1 Logarithmic/Linear analog output............................................................................... 70
8.4.2 Combination analog output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 0
8.4.3 Logarithmic/Linear analog output when the gauge power is turned off ..................... 72
9 937B RS232/485 Serial Communication Commands............................................................. 73
9.1 Communication protocols.............................................................................................. 73
9.2 Pressure reading commands ........................................................................................ 74
9.3 Relay and control setting commands ............................................................................ 75
9.4 Capacitance manometer control commands ................................................................ 76
9.5 Pirani and convection Pirani control commands ........................................................... 76
9.6 Cold cathode control commands................................................................................... 77
9.7 Hot cathode control commands .................................................................................... 78
9.9 System commands........................................................................................................ 79
9.10 Error code...................................................................................................................... 80
9.11 937B ProfiBus communication protocol and commands .............................................. 81
9.11.1 Electrical Connections................................................................................................ 81
9.11.2 ProfiBus GSD protocol ............................................................................................... 81
9.11.3 937 ProfiBus output buffer map ................................................................................. 83
9.11.4 937B ProfiBus input buffer map ................................................................................. 85
10 937A Emulated Operation and RS232/485 Serial Communication Commands..................... 88
10.1 Operating the 937B controller in 937A emulated operation mode................................ 88
10.2 Communication protocols.............................................................................................. 90
10.3 Pressure reading commands ........................................................................................ 91
10.4 Relay and control setting commands ............................................................................ 92
10.5 Cold cathode control commands................................................................................... 92

MKS 937B Operation Manual 4
10.6 User calibration commands........................................................................................... 93
10.7 System commands........................................................................................................ 93
10.8 ASCII character table .................................................................................................... 94
11 Maintenance of Series 937B Controller modules ................................................................... 95
11.1 Removing and Installing a Sensor Module.................................................................... 95
11.2 Removing and Installing AIO Module............................................................................ 96
11.3 Communication Module................................................................................................. 97
11.4 Power Supply ................................................................................................................ 97
11.5 Mounting the 937B controller ........................................................................................ 98
11.6 AC Power Cord ............................................................................................................. 99
12 Maintenance and Service of HPSVacuum Sensors........................................................... 100
12.1 421 Cold cathode sensor ............................................................................................ 100
12.1.1 Cold cathode theory................................................................................................. 100
12.1.2 Maintenance of Series 421/422 Cold Cathode Sensor............................................ 101
12.2 Maintenance of Series 423 I-MAG®Cold Cathode Sensor........................................ 104
12.2.1 Connecting the I-MAG Sensor ................................................................................. 104
12.2.2 Disassembling the I-MAG Sensor............................................................................ 104
12.2.3 Cleaning the I-MAG Sensor ..................................................................................... 106
12.2.4 Assembling the I-MAG Sensor................................................................................. 106
12.2.5 Preparing the Sensor for Bakeout............................................................................ 107
12.3 Maintenance of Low Power Nude and Mini BA hot cathode sensors ......................... 107
12.3.1 Hot cathode theory................................................................................................... 107
12.3.2 Cleaning the Hot Cathode Sensor ........................................................................... 108
12.3.3 Testing the hot cathode sensor................................................................................ 109
12.4 Maintenance of Pirani Sensors ................................................................................... 109
12.4.1 Theory of a Pirani pressure sensor.......................................................................... 109
12.4.2 Cleaning the Series 345 Sensor .............................................................................. 110
12.4.3 Cleaning the Series 317 Sensor .............................................................................. 111
12.5 Maintenance of Capacitance Manometer ................................................................... 112
12.5.1 Theory of a capacitance manometer ....................................................................... 112
12.5.2 Repairing the Baratron™ Capacitance Manometer................................................. 113
13 Spare Parts and Accessories................................................................................................ 114
14 APPENDIX ............................................................................................................................ 117
14.1 Hot cathode gauge gas correction factors .................................................................. 117
15 Product Warranty .................................................................................................................. 120

MKS 937B Operation Manual 5
List of Figures
Figure 3-1 937B front Panel..................................................................................................................... 17
Figure 3-2 937B rear panel. ..................................................................................................................... 17
Figure 3-3 937B external dimensions (inches). ......................................................................................... 18
Figure 5-1 937B front view......................................................................................................................... 20
Figure 6-1 Standard 937B LCD front panel display for pressure measurement under Leak detection
mode................................................................................................................................................... 22
Figure 6-2 A comparison between standard display mode and large font display mode for the 937B LCD
display during pressure measurement. .............................................................................................. 24
Figure 6-3 937B system setup parameters, their default values and ranges. ......................................... 24
Figure 6-4 System setup information displayed on 937B LCD screen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 5
Figure 6-5 Setting DAC logarithmic and linear analog output..................................................................... 28
Figure 6-6 System firmware and serial number information displayed on 937B LCD screen.................... 29
Figure 6-11 Hot cathode setup information displayed on 937B LCD screen............................................ 41
Figure 7-1 13 pin D-Sub connector on the back of 937B HC board. ....................................................... 50
Figure 7-2 LPN gauge cable diagram. ..................................................................................................... 51
Figure 7-3 Mini BA gauge cable diagram................................................................................................. 51
Figure 7-4 317/345 cable diagram. .......................................................................................................... 53
Figure 7-5 The wiring diagram for the Capacitance Manometer cable.................................................... 55
Figure 8-1 Definition of the parameters used for relay control................................................................. 57
Figure 8-2 The relay arc suppression network. ....................................................................................... 58
Figure 8-3 Buffered analog output for cold cathode gauges (421/422/423) in N2. .................................. 60
Figure 8-4 Buffered analog output for hot cathode gauges; same as the logarithmic analog output...... 62
Figure 8-5 Buffered analog output for a 345 Pirani gauge....................................................................... 63
Figure 8-6 Buffered analog output for the 317 convection Pirani gauge. ................................................ 66
Figure 8-7 Buffered analog output for capacitance manometers. ........................................................... 69
Figure 8-8 Setup screen for setting combination channel parameters. ...................................................... 71
Figure 11-1 Instructions for removing AIO module. ................................................................................. 96
Figure 11-2 Instruction for connecting wire on the back of the power cord receptor............................... 97
Figure 11-3 The 937B controller power supply........................................................................................ 98
Figure 12-1 A comparison of Inverted Magnetron (left) and Penning (right) cold cathode gauges....... 100
Figure 12-2 Electron orbits and ion production in an inverted magnetron............................................. 101
Figure 12-3 An exploded view of the 421/422 cold cathode gauge assembly. .....................................102
Figure 12-4 An exploded view of the Series 423 I-MAG cold cathode gauge sensor. .......................... 105
Figure 12-5 BA gauge structure and electron process inside the gauge............................................... 108
Figure 12-6 Filament pin locator for LPN and mini BA gauges.............................................................. 109
Figure 12-7 Schematic of a Pirani thermal conductivity sensor............................................................. 110
Figure 12-8 Natural convection heater transfer in horizontal (left) and vertical (right) sensor tubes..... 110
Figure 12-9 Exploded view of a MKS Capacitance manometer sensor. ...............................................112

MKS 937B Operation Manual 6
List of Tables
Table 6-1 Valid gauges for autozeroing capacitance manometers of different ranges. .......................... 33
Table 6-2 Relative ionization correction factor to N2 for different gases. ................................................ 41
Table 6-3 Pin out for ion gauge remote control. ...................................................................................... 45
Table 7-1 Hot cathode connector pin out................................................................................................. 50
Table 7-2 Pin assignment for HC sensor type identification. ................................................................... 51
Table 7-3 Pin out for 317/345 cables. ...................................................................................................... 53
Table 7-4 Pin out of the 9 pin D-Sub connector on CM module. ............................................................. 54
Table 8-1 Pin out for the 937B relay output. ............................................................................................ 56
Table 8-2 Pin out for 937B analog output. ............................................................................................... 59
Table 8-3 Buffered analog output when sensor power is off. .................................................................... 59
Table 8-4 Buffered analog output for the cold cathode gauges (421/422/423) in N2. This is 2.4 higher
than the raw analog output as shown in Table 8-5. ........................................................................... 61
Table 8-5 Equations for Cold Cathode gauges (N2) raw analog output................................................... 61
Table 8-6 Buffered analog output for the 315/345 Pirani sensors. .......................................................... 64
Table 8-7 Equations for the 315/345 Pirani sensors................................................................................. 65
Table 8-8 Buffered analog output for the 317 Convection Pirani sensor. ................................................ 67
Table 8-9 Equations for the 317 Convection Pirani sensor. .................................................................... 68
Table 9-1 937B serial communication wiring diagram. .............................................................................. 73
Table 9-2 937B serial communication command protocol.........................................................................7 3
Table 9-3 937B pressure reading commands............................................................................................ 74
Table 9-4 937B relay and control serial setting commands....................................................................... 75
Table 9-5 937B capacitance manometer serial commands..................................................................... 76
Table 9-6 937B Pirani and Convection Pirani control commands. .......................................................... 76
Table 9-7 937B cold and hot cathode control commands. ......................................................................7 7
Table 9-8 937B cold and hot cathode control commands. ......................................................................7 8
Table 9-13 937B system commands. ...................................................................................................... 80
Table 9-14 937B serial communication error codes. ............................................................................... 80
Table 9-15 937B Profibus electrical connections........................................................................................ 81
Table 9-16 937B ProfiBus command list..................................................................................................... 82
Table 9-17 937B ProfiBus output buffer map.............................................................................................. 84
Table 9-18 937B ProfiBus input buffer map................................................................................................ 87
Table 10-1 Description of pin assignment for adapting 937A 15 pin connector to 937B 25 pin connector
for relay output.................................................................................................................................... 88
Table 10-2 A description of the pin assignments for adapting the 937A 25 pin connector to the 937B 37
pin connector for analog output and gauge control when a dual PR/CM board is installed in slot A.89
Table 10-3 A description of the pin assignments for adapting the 937A 25 pin connector to the 937B 37
pin connector for analog output and gauge control when a CC board is installed in slot A............... 89
Table 10-4 937B serial communication wire diagram. ............................................................................... 90
Table 10-5 The 937A serial communication command protocol.............................................................. 90
Table 10-6 937A pressure reading serial commands. ............................................................................. 91
Table 10-7 The 937A relay and control setting commands. ....................................................................9 2
Table 10-8 The 937A cold cathode control commands. .......................................................................... 92
Table 10-9 937A user calibration commands. ......................................................................................... 93
Table 10-10 937A system commands. .................................................................................................... 93
Table 10-11 ASCII character table........................................................................................................... 94
Table 12-1 Resistance readings of a normal HC sensor. ...................................................................... 1 0 9
Table 12-2 Bridge resistance value for a normal 345 Pirani sensor...................................................... 111
Table 12-3 Resistance values for a normal 317 convection enhanced Pirani sensor........................... 112

MKS 937B Operation Manual 7
Package Contents
Before unpacking the 937B high vacuum, multi-sensor system controller, check all
surfaces of the packing material for shipping damage.
Please be sure that the 937B system contains the following items:
 1 Series 937B controller (with selected modules installed)
1female,25-pinDsubconnectorforrelayoutputconnection
1male,37pinDsubconnectorforanalogoutputconnection
110-footpowercord(UScustomeronly)
1HPS
TM Products Series 937B User’s Manual CD
If any items are missing from the package, call HPS®Products Customer Service
Department at 1-303-449-9861 or 1-800-345-1967.
Inspect the 937B system 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 HPS®Products.

MKS 937B Operation Manual 8
1 Safety Information
1.1 Symbols Used in this Manual and their definitions
CAUTION: Risk of electrical shock.
CAUTION: Refer to manual. Failure to read message could result
in personal injury or serious damage to the equipment or both.
CAUTION: Hot surface.
Calls attention to important procedure, practice, or conditions.
Failure to read message could result in damage to the equipment.
1.2 Safety Precautions
1.2.1 Safety Procedures and Precautions
The following general safety precautions must be observed during all phases of operation of this
instrument. Failure to comply with these precautions or with specific warnings elsewhere in this manual
violates safety standards for the intended use of the instrument and may impair the protection provided by
the equipment. MKS Instruments, Inc. assumes no liability for the customer’s failure to comply with these
requirements.
Properly ground the Controller.
This product is grounded through the grounding conductor of the power cord. To avoid electrical shock,
plug the power cord into a properly wired receptacle before connecting it to the product input or output
terminals. A protective ground connection through the grounding conductor in the power cord is essential
for safe operation.
Upon loss of the protective-ground connection, all accessible conductive parts (including knobs and
controls that may appear to be insulating) can render an electrical shock.
Do not substitute parts or modify the instrument.
Do not install substitute parts or perform any unauthorized modification to the instrument. Return the
instrument to an MKS Calibration and Service Center for service and repair to ensure that all safety
features are maintained.

MKS 937B Operation Manual 9
Use proper electrical fittings.
Dangerous voltages are contained within this instrument. All electrical fittings and cables must be of the
type specified, and in good condition. All electrical fittings must be properly connected and grounded.
The Series 937B Controller contains lethal voltages when on.
High voltage is present in the cable and a cold cathode sensor when the Controller is turned on.
Use the proper power source.
This product is intended to operate from a power source that applies a voltage between the supply
conductors, or between either of the supply conductors and ground, not more than that specified in the
manual.
Use the proper fuse.
Only use a fuse of the type, voltage rating, and current rating specified for your product.
Do not operate in explosive environment.
To avoid explosion, do not operate this product in an explosive environment unless it has been specially
certified for such operation.
Service by qualified personnel only.
Operating personnel must not remove instrument covers. Component replacement and internal
adjustments must only be made by qualified service personnel.
Use proper power cord.
Only use a power cord that is in good condition and that meets the input power requirements specified in
the manual.
Only use a detachable cord set with conductors having a cross-sectional area equal to or greater than
0.75 mm2. The power cable should be approved by a qualified agency such as VDE, Semko, or SEV.

MKS 937B Operation Manual 10
2 Specifications1
2.1 Controller
Pressure measuring range21x10
-11 to 2.0 x 10+5 Torr
1x10
-11 to 2.6 x 10+5 mbar
1x10
-9 to 2.6 x 10+7 Pa
Relay set point range3
CC(ColdCathode) 2.0x10
-10 to 5.0 x 10-3 Torr
2.7x10
-10 to 6.5 x 10-3 mbar
2.7x10
-8 to 6.5 x 10-1 Pa
HC (Hot Cathode) 5.0x10
-10 to 5.0 x 10-3 Torr
6.5x10
-10 to 6.5 x 10-3 mbar
6.5x10
-8 to 6.5 x 10-1 Pa
Pirani 2.0x10
-3 to 9.5 x 10+1 Torr
2.7x10
-3 to 1.2 x 10+2 mbar
2.7x10
-1 to 1.2 x 10+4 Pa
CP (Convection Pirani) 2.0x10
-3 to 9.5 x 10+2 Torr
2.7x10
-3 to 1.2 x 10+3 mbar
2.7x10
-1 to 1.2 x 10+5 Pa
CM (Capacitance Manometer) 1%to95%ofthemeasurementrangeofthehead(e.g.1Torr
head is1.0 x 10-2 to 9.5 x 10-1 Torr)
Allowed range within which a control gauge may switch on a cold or hot cathode
Pirani 5.0x10
-4 to 9.5 x 10-1 Torr
6.5x10
-4 to 1.3 x 10-1 mbar
6.5x10
-2 to 1.3 x 101Pa
CP (Convection Pirani) 2.0x10
-3 to 9.5 x 10-1 Torr
2.7x10
-3 to 1.3 x 10-1 mbar
2.7x10
-1 to 1.3 x 101Pa
Protection setpoint4
CC & HC 1.0x10-5 to 1.0x10-2 torr, default setting: 5.0x10-3 Torr
Operating temperature range 5°to40°C (41°to104°F)
Storage temperature range -10°to55°C(14°to131°F)
Relative humidity 80%maximumfortemperatureslessthan31°C,decreasing
linearly to 50% maximum at 40°C
Altitude 2000m(6561ft)maximum
Insulation coordination Installation(Over-voltage)Category II, Pollution Degree 2
1Design and/or specifications are subject to change without notice.
2The measurement range depends upon the sensor options selected.
3Relay setpoint values are automatically adjusted when pressure unit is changed.
4The protection setpoint is always enabled in 937B.

MKS 937B Operation Manual 11
Power requirement (nominal) 100-240VAC,50/60Hz
Mains voltage Fluctuationsnottoexceed±10%ofnominal
Power consumption 150 W maximum
Fuse rating, size 2X2A,250V,Ø5mmx20mm
Process control relay 12nonvolatilerelays,(4foreachsensormodule)
Relay rating SPDT,2A@30Vresistive
Relay response 150 msec maximum
Analog outputs5One Buffered and one Logarithmic/Linear for each channel, up to
two (2) wide-range combination logarithmic outputs. Output
impedance = 100 ohms
Number of channels up to 6
Front panel controls Power on-off switch, setup and operational commands can be
accessed via the keypad.
Display 320x240 color QVGA TFT LCD with back lighting.
Pressure units Torr, mbar, Pascal or microns
Update rate LCD display is updated 3 times per second. The pressure/flow
signals are updated every 50 msec.
Leak test 25-segment bar graph with a variable rate audio signal
Sensor module slots 3
Sensor modules channels/module
Cold Cathode single
Hot Cathode single
Pirani/Convection Pirani dual
Capacitance Manometer dual
COMM/Control modules
ProfiBus
PressureControl
Computer interface Serial – RS-232 and RS-485 9600, 19200, 38400,57600,115200
baud rate selectable
Electronic casing Aluminum
Dimensions (W x D x H) 9½" x 12¼" x 3½" (241 mm x 311 mm x 88 mm)
Size ½rack, 2U high
Typical weight 8.0 lb (3.6 kg)
CE certification EMC Directive: 2004/108/EEC
Low Voltage Directive: 73/23/EEC
5Logarithmic/linear and combined logarithmic analog outputs can be customized using the system setup
manual.

MKS 937B Operation Manual 12
2.2 Sensors
Sensor type
CC (Cold Cathode) Series421and422invertedmagnetron
Series 423 I-MAG®
HC (Hot Cathode) Bayard—Alpert(BA)typeionizationgaugesincludingHPSMIG
(Miniature Ionization Gauge, or LPN (Low Power Nude), glass
enveloped gauges and UHV nude type.
Pirani Series 345 Pirani
CP (Convection Pirani) Series 317 Convection Pirani
(CM) Capacitance Manometer MKSunheatedBaratron
®(622A, 623A, 626A, 722A );
MKS 45 C heated Baratron®(624B,D24B, 627B,D27B);
MKS differential Baratron®
Pressure measurement range
CC(ColdCathode) 1.0x10
-11 to 1.0 x 10-2 Torr
1.3x10
-11 to 1.3 x 10-2 mbar
1.3x10
-9 to 1.3 x 10+0 Pa
HC (Hot Cathode) 1.0x10
-10 to 1.0 x 10-2 Torr
1.3x10
-10 to 1.3 x 10-2 mbar
1.3x10
-8 to 1.3 x 10+0 Pa
HC with UHV type gauge 2 .0x 10-11 to 1.0 x 10-2 Torr
2.3x10
-11 to 1.3 x 10-2 mbar
2.3x10
-10 to 1.3 x 10+0 Pa
Pirani 5.0x10
-4 to 4.0 x 10+2 Torr
6.5x10
-4 to 5.2 x 10+2 mbar
6.5x10
-2 to 5.2 x 10+4 Pa
CP (Convection Pirani) 1.0x10
-3 to 1.0 x 10+3 Torr
1.3x10
-3 to 1.3 x 10+3 mbar
1.3x10
-1 to 1.3 x 10+5 Pa
(CM) Capacitance Manometer Three decades below full scale of head, (e.g., 10 Torr head is1.0
x 10-2 to 1.0 x 10+1 Torr)
Response time (Buffered analog output)
CC <40msec
6
HC <50msec
Pirani, CP <80msec
CM <40msec
Response time (Log/Lin analog output)
CC <50msec
HC <50msec
6A fast response (<3 msec) cold cathode board is also available. Please consult the factory for details.

MKS 937B Operation Manual 13
Pirani, CP <80msec
CM <80msec
Resolution7
CC & HC 2significantdigitsbetween10
-10 and 10-3 Torr, 1 significant digit
in 10-11 and 10-2 Torr decades
Pirani 2significantdigitsbetween10
-3 and 99 Torr, 1 significant digit
elsewhere within the gauge’s range
CP 2 significant digits
CM 4 significant digits
Repeatability
CC,HC,Pirani,CP 5% of indicated pressure at constant temperature
CM 0.25%ofindicatedpressureatconstanttemperature
Calibration gas
CC, HC Nitrogen, Argon
Pirani, CP Air/nitrogen,Argon,Helium
CM Any (gas independent)
Installation orientation
CC,HC,CM,Pirani Any(portdownsuggestedforpressuresensor)
CP Body horizontal only
Materials exposed to vacuum may include
CC Series 421 and 422 – SS 304, Al 6061, silver-copper brazing
alloy, alumina ceramic, Elgiloy®, OFHC®copper
Series 423 – SS 302, SS 304, glass, Al, Inconel X-750®, alumina
ceramic
HC 304 SS, Inconel®X750, glass, tungsten, platinum clad
molybdenum, tantalum, nickel, braze alloy, either yttria coated
iridium or tungsten filament
Pirani 300 series stainless, platinum, alumina ceramic, silver brazing
alloy, nickel 200
CP 300seriesstainless,nickel,glass,platinum
CM Inconel
®
Internal volume8
CC Series421and422-1.8in
3(30 cm3)
Series 423 - 0.9 in3(15 cm3)
7Trailing zeros displayed on LCD screen do not reflect the resolution of the pressure reading.
8Volume will vary with the type of vacuum connection selected

MKS 937B Operation Manual 14
HC Low power nude tube - zero
MiniBA-1.4in
3(23 cm3)
Pirani 0.5 in3(8 cm3)
CP 2.0 in3(33 cm3)
CM Type622A/623A/626A-0.38in.
3(6.3 cm3)
Type 722A -0.3 in.3(4.9 cm3)
Operating temperature range
CC Series421-0°to70°C(32°to158°F)
Series 422--Versions available that operate up to 250°C.
Series 423 - 0° to 70°C (32° to158°F)
Pirani & HC 0°to50°C(32°to122°F)
CP 10°to50°C(50°to122°F)
CM 0°to50°C(32°to122°F)
Maximum bakeout temperature (Without controller or cables)
CC Series421–250°C(482°F)whenbackshellsubassembly
removed, 125°C (257°F) otherwise
Series 422 and 423 – 400°C (752°F) CF flange version only with
magnet removed
HC 60oC with cable attached
300oC max, with CF, cable removed
150oC, with KF and Viton®seal, cable removed
Pirani 50°C(122°F)
CP 100°C (212°F) RF shielded with coated plastic shell installed
150°C (302°F) Partial shell disassembly required
250°C RF shield via aluminum housing
CM N/A
Radiation (<107rad)
CC Series 422 with Lemo connector
CP 317 with aluminum housing
Hot cathode sensitivity
LPN 9 Torr-1 (20%)
Mini BA 12Torr
-1 (20%)
Glass BA 7.5 to 25 Torr-1 (depend upon the sensor design)
Hot Cathode filament type
LPN & Mini BA Tungsten (W) or Yittria (Y2O3) coated iridium
Glass BA Tungsten (W), Yittria (Y2O3) coated iridium or
Thoria (ThO) coated iridium
Hot Cathode degas power (E-beam, at grid)

MKS 937B Operation Manual 15
LPN 20 W max
Mini BA 5Wmax
Glass BA 50Wmax
Ion gauge operating voltages
HC Grid: 180 VDC (normal operation); up to 600 V during degas
Filamentbias:30VDC
Filament:1.8VDC@2A
CC 4.0 kVDC
Hot Cathode X-ray limit
LPN & Mini BA 3x10-10 Torr9
Dimensions
CC Series421and422–2.26.3 in (56160 mm)
Series 423 – 2.63.4 in (6686 mm)
Mini BA 1.12X2.37 in (2860 mm) with 2-3/4” CF flange
LPN 3.3X1.0 in (83 mm25) with 2-3/4 CF flange, can insert into
NW40 tube.
Pirani 1.3X4.4 in (34112 mm)
CP 1.6X4.4 in (41112 mm)
CM Types622A,623Aand626A-2.64.8 in. (66121 mm)
Type 722A- 1.53.9 in (3899 mm)
Typical Weight (with 2¾” CF Flange)
CC 421and422-2.4lb(1.1kg)
423 - 1.8 lb (0.8 kg)
LPN 0.9 lb (0.40 kg) with CF flange
Mini BA 0.816 lb (0.36 kg) with CF flange
Pirani 0.5 lb (0.2 kg)
CP (w/ KF Flange) 0.5lb(0.2kg)
Vacuum Connection
CC KF25,KF40,2-3/4”CF,8VCR
®-F (1/2”), 1” tubing
LPN 2-3/4”CF(non-rotatable),KF40
Mini BA KF16,KF25,KF40,2-3/4”CF,1-1/3”miniCF,3/4”,1”ODtubing
Pirani, CP KF16, KF25, 1/8” NPT-M with 1/2” compression seal,
8VCR
®-F, 4 VCR®-F, 1-1/3" CF (non-rotatable),
2-3/4”CF(non-rotatable)
CM KF16,8VCR
®-F (1/2”), 8 VCO®-F (1/2”),1-1/3” CF (non-
rotatable), ½” tube
9The hot cathode X-ray limit can be corrected by using a serial command. See section 9.6 for details.

MKS 937B Operation Manual 16
2.3 Controller Display Messages
X.X0Eee Normal pressure for the Pirani, CP, CC, and HC
X.XXXEe Normal pressure for the Baratron
OVER The pressure is over upper limit (for CC and HC when p > protected
setpoint)
ATM Atmospheric pressure for the Pirani sensor
>1.100Ee CM pressure is over 10% of the full scale
LO<E-11 The CC pressure is below its lower limit, or no CC gauge is connected
LO<E-10 The HC pressure is below its lower limit
LO<E-04 The Pirani pressure is below its lower limit
LO<E-03 The CP pressure is below its lower limit
OFF The HC filament is off, or the CC high voltage is off
WAIT CC and HC startup delay
LowEM The HC off due to low emission current
CTRL_OFF The HC or CC are turned off by the control channel
PROT_OFF The HC or CC are in a protected state
RP_OFF The sensor power is turned off remotely
REDETECT Detecting the sensor type for PR/CP
MISCONN A sensor is improperly connected, or there is a broken filament (Pirani, CP,
CM, HC)
_ _ _ _ No Pirani/CP/HC sensor is detected on the inserted Pirani/CP board
NOBOARD No board is detected in the slot, display only last 5 secs
N2, AR, He Gas type
U User calibration
SPn Activated relay channel (n=1 to 12)
_ _ A relay is enabled, but not activated.
Ctrl The CC/HC is controlled by another gauge (PR/CP)
AZ PR/CP/BR may be auto-zeroed by its control gauge
F1, F2 Active filament
DG The HC is degassing
An, Bn, Cn The channel where the control gauge is installed (n=1, 2)

MKS 937B Operation Manual 17
3 Feature, Control Locations and Dimensions
Figure 3-1 937B front Panel.
RELAY OUTOUT
Communication
ANALOG
100 - 240 VAC 50/60 HZ 150 WATTS FUSE: 2.0 AT
COLD CATHODE
PIRANI
CAPACITANCE MANOMETER
Figure 3-2 937B rear panel.

MKS 937
B
B
Operation M
a
1
C
h
2
L
E
3
Li
q
4
P
u
5
P
o
6
A
I
O
7
AC
8
R
S
9
R
e
10
An
11
C
o
12
C
o
13
Hi
g
14
C
u
15
Pi
r
16
C
a
a
nual
Figure
h
annel label
E
D, indicating
q
uid Crystal
D
u
sh Buttons f
o
o
wer Switch
O
Module
C
Power Inlet
S
232/485 Co
m
e
lay Output P
o
n
alog Output
P
o
mmunicatio
n
o
ld Cathode
M
g
h Voltage B
N
u
rrent BNC c
o
r
ani Module
a
pacitance m
a
3-3 937B e
x
active chann
D
isplay
o
r menu navi
g
m
munication
o
rt
P
ort
n
/Valve Contr
o
M
odule
N
C connecto
r
o
nnector
a
nometer Mo
18
x
ternal dime
n
el
g
ation
Port
o
l Module
r
dule
n
sions (inch
e
e
s).

MKS 937B Operation Manual 19
4 Typical Applications for the Series 937B
Controller
The measurement of pressure in high vacuum chambers.
 Pressure control in high vacuum systems and process sequencing using relay set points.
 Sensing abnormal pressure events and initiating and controlling appropriate security
measures using the relay set points.
Controllingsystempressurebyusingtheanalogoutput as the input to an automatic pressure
controller.
Startingorstoppingsystemprocessesusingrelaysetpoints.
 Measuring backfill pressures.
Leaktestingvacuumsystems.
Controllingaccelerationandlightsourcevacuumsystems.

MKS 937
B
5 H
P
Va
T
HE HPS
®
pressure
listed bel
o

M

M

M

M

M
With thre
e
Series 93
versatility
including:
P

U
T

R
T
T
T
B
Operation M
a
P
SP
r
a
cuum
®
P RODUCTS
S
m
easuremen
o
w can be co
n
M
KS Baratron
M
KS 423 I-M
A
M
KS Lower p
o
M
KS Series 3
4
M
KS Series 3
1
e
sensor mo
d
7B Controlle
r
and ease-of
-
ressure mea
s
U
nits of the in
d
he type of pr
e
R
elay status (
b
he operating
he control st
a
he auto zero
a
nual
r
oduct
s
Syste
S
ERIES 937B
t between 1
n
nected to th
e
Capacitance
A
G or Series
4
o
wer nude ga
4
5 Pirani sen
s
1
7 Convectio
n
d
ule slots ava
r
can accom
m
-
use in mind,
s
urements fo
r
d
icated press
e
ssure senso
b
oth enabled
status of Hot
a
tus of ion ga
channel for
p
s
Seri
e
m
Multi-Sensor
10
-11
torr to
2
e
937B:
Manometer
s
4
21/422 Cold
uge or mini
B
s
ors (up to 6
)
n
Pirani sens
o
Figure 5-
1
ilable and th
e
m
odate many
with a large
L
r
all sensors
c
ures (Torr, m
r (CM, CC, P
and activate
d
Cathode ga
u
uges
p
irani/CP/CM
20
e
s 937
B
High Vacuu
m
2
10
+5
torr. A
s
with heads
f
Cathode Se
n
B
A Hot Catho
d
o
rs (up to 6)
1
937B fron
t
e
ability to co
n
unique requi
r
L
CD screen t
h
c
onnected to
bar, Pa, micr
R, CP, HC) (
s
d
relays are
d
u
ge (active fil
a
sensors
B Mul
t
m
System pr
o
number of di
f
f
rom 0.02 to
2
n
sors (up to
3
d
e sensors (
u
t
view.
n
figure a vari
e
r
ements and
h
at displays
m
the controlle
r
r
ons)
s
elf-detectin
g
d
isplayed)
a
ment, dega
s
t
i-Sen
s
o
vides accur
a
f
ferent MKS
p
2
0,000 torr (u
3)
u
p to 3)
e
ty of sensor
applications.
m
uch useful i
n
r (up to 6)
g
)
s
)
s
or Hi
g
a
te and reliab
l
p
ressure sen
s
p to 6)
combination
s
It is designe
d
n
formation,
g
h
l
e
s
ors,
s
, the
d
with