INFICON BPG402-Sx User Manual

Operating Manual

Bayard-Alpert Pirani Gauge

Dual Filament Bayard-Alpert Pirani Gauge

BPG402-S
BPG402-SD
BPG402-SL
BPG402-SP

tina46e1-a (2010-03) 1

Product Identification

In all communications with INFICON, please specify the information on the product
nameplate. For convenient reference copy that information into the space provided
below.

INFICON AG, LI-9496 Balzers

Model:
PN:
SN:
V W

Validity

Intended Use

This document applies to products with the following part numbers:
BPG402-S (without display, one switching function )

353-570
353-571

(vacuum connection DN 25 ISO-KF)
(vacuum connection DN 40 CF-R)

BPG402-S (with display, one switching function)

353-572
353-573

(vacuum connection DN 25 ISO-KF)
(vacuum connection DN 40 CF-R)

BPG402-SL (without display, one switching function)

353-571

(vacuum connection DN 40 CF-R, long tube)

BPG402-SD (with DeviceNet interface and two switching functions)

353-576
353-577

(vacuum connection DN 25 ISO-KF)
(vacuum connection DN 40 CF-R)

BPG402-SP (with Profibus interface and two switching functions)

353-574
353-575

(vacuum connection DN 25 ISO-KF)
(vacuum connection DN 40 CF-R)

The part number (PN) can be taken from the product nameplate.

If not indicated otherwise in the legends, the illustrations in this document
correspond to gauge with part number 353-572. They apply to the other gauges by
analogy.

We reserve the right to make technical changes without prior notice.
All dimensions in mm.

The BPG402-Sx gauges have been designed for vacuum measurement of non­flammable gases and gas mixtures in a pressure range of 5×10

-10

… 1000 mbar.

The gauges can be operated in connection with the INFICON Vacuum Gauge
Controller VGC40x or with other control devices.

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Functional Principle

Over the whole measuring range, the gauge has a continuous characteristic curve
and its measuring signal is output as logarithm of the pressure.

The gauge functions with a Bayard-Alpert hot cathode ionization measurement
system (for p < 2.0×10
p > 5.5×10

2.0×10

-3

mbar). In the overlapping pressure range of

-2

… 5.5×10-3 mbar, a mixed signal of the two measurement systems is
output. The hot cathode is switched on by the Pirani measurement system only
below the switching threshold of 2.4×10
switched off when the pressure exceeds 3.2×10

-2

mbar) and a Pirani measurement system (for

-2

mbar (to prevent filament burn-out). It is

-2

mbar.

BPG402-Sx sensors are equipped with two hot cathodes. The identical filaments
are monitored by the gauge electronics. In case of a filament failure, the gauge will
switch over to the second (undamaged) filament and continue to operate. The
filament status is displayed on the gauge or can be read via the interfaces
(RS232C, DeviceNet or Profibus).

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Contents

Product Identification 2
Validity 2
Intended Use 2
Functional Principle 3

Safety 6

1

1.1 Symbols Used 6

1.2 Personnel Qualifications 6

1.3 General Safety Instructions 7

1.4 Liability and Warranty 7

2 Technical Data 8
3 Installation 13

3.1 Vacuum Connection 13

3.1.1 Removing and Installing the Electronics Unit 14

3.1.2 Using the Optional Baffle 15

3.2 Electrical Connection 17

3.2.1 Use With INFICON VGC40x Vacuum Gauge Controller 17

3.2.2 Use With Other Controllers 17

3.2.2.1 Making an Individual Sensor Cable 18

3.2.2.2 Making a DeviceNet Interface Cable (BPG402-SD) 21

3.2.2.3 Making a Profibus Interface Cable (BPG402-SP) 22

3.2.3 Using the Optional Power Supply (With RS232C Line) 23

4 Operation 25

4.1 Measuring Principle, Measuring Behavior 25

4.2 Operational Principle of the Gauge 27

4.3 Putting the Gauge Into Operation 27

4.4 Degas 27

4.5 Filament Status 28

4.5.1 Filament Status Indicator 28

4.5.2 Filament Status Relay (Only BPG402-S) 28

4.5.3 Filament Status via Interface 28

4.6 Filament Control Mode 28

4.7 Emission Control Mode 29

4.8 Display (BPG402-S) 29

4.9 RS232C Interface 30

4.9.1 Description of the Functions 30

4.9.1.1 Output String (Transmit) 31

4.9.1.2 Input String (Receive) 33

4.10 DeviceNet Interface (BPG402-SD) 34

4.10.1 Description of the Functions 34

4.10.2 Operating Parameters 34

4.10.2.1 Operating Software 34

4.10.2.2 Node Address Setting 34

4.10.2.3 Data Rate Setting 35

4.10.3 Status Indicators 35

4.11 Profibus Interface (BPG402-SP) 36

4.11.1 Description of the Functions 36

4.11.2 Operating Parameters 36

4.11.2.1 Operating Software 36

4.11.2.2 Node Address Setting 36

4.12 Switching Functions 37

4.12.1 Setting the Switching Functions 38

5 Deinstallation 39
6 Maintenance, Repair 41

6.1 Cleaning the Gauge 41

6.2 Adjusting the Gauge 41

6.2.1 Adjustment at Atmospheric Pressure 41

6.2.2 Zero Point Adjustment 42

6.3 What to Do in Case of Problems 42

6.4 Replacing the Sensor 44

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7 Options 45
8 Spare Parts 45
9 Storage 45
10 Returning the Product 46
11 Disposal 46

Appendix 47

A: Relationship Output Signal – Pressure 47
B: Gas Type Dependence 48
C: Literature 50

Declaration of Contamination 51

For cross-references within this document, the symbol (→  XY) is used, for cross-
references to further documents and data sources, the symbol (→  [Z]).

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1 Safety

1.1 Symbols Used

DANGER

Information on preventing any kind of physical injury.

WARNING

Information on preventing extensive equipment and environmental damage.

Caution

Information on correct handling or use. Disregard can lead to malfunctions or
minor equipment damage.

Notice

1.2 Personnel Qualifications

Hint, recommendation

The result is O.K.

The result is not as expected

Optical inspection

Waiting time, reaction time

Skilled personnel

All work described in this document may only be carried out by persons who
have suitable technical training and the necessary experience or who have been
instructed by the end-user of the product.

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1.3 General Safety
Instructions

1.4 Liability and Warranty

• Adhere to the applicable regulations and take the necessary precautions for the
process media used.

Consider possible reactions between the materials (→  11) and the process
media.

Consider possible reactions of the process media (e.g. explosion) due to the
heat generated by the product.

• Adhere to the applicable regulations and take the necessary precautions for all
work you are going to do and consider the safety instructions in this document.

• Before beginning to work, find out whether any vacuum components are con­taminated. Adhere to the relevant regulations and take the necessary precau­tions when handling contaminated parts.

Communicate the safety instructions to all other users.

INFICON assumes no liability and the warranty becomes null and void if the end­user or third parties

• disregard the information in this document

• use the product in a non-conforming manner

• make any kind of interventions (modifications, alterations etc.) on the product

• use the product with accessories not listed in the corresponding product docu-

mentation.

The end-user assumes the responsibility in conjunction with the process media
used.

Gauge failures due to contamination, as well as expendable parts (filament), are
not covered by the warranty.

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2 Technical Data

Measurement

Emission

Degas

Output signal

Gauge identification

Measurement range (air, O2, CO, N2) 5×10
Accuracy

(after 10 min. stabilization)
Repeatability

(after 10 min. stabilization)

-10

… 1000 mbar, continuous

15% of reading in the range of
1×10-8 … 10-2 mbar

5% of reading in the range of
1×10-8 … 10-2 mbar

Gas type dependence → Appendix B

Switching on threshold
Switching off threshold

Emission current

p ≤7.2×10

7.2×10

-6

mbar

-6

mbar < p < 3.2×10-2 mbar

Emission current switching

25 µA ⇒ 5 mA
5 mA ⇒ 25 µA

Filaments

Number
Means of selection

2.4×10-2 mbar

-2

3.2×10

mbar

5 mA
25 µA

7.2×10-6 mbar

-5

3.0×10

mbar

2
Controlled by gauge (default) or via

interfaces (→  33,  [1] and  [9])

Settling time of measurement signal
after filament change

Filament status

Emission control mode

Automatic
Manual

<4 s
LED, relay contact (→  28)

Emission ON/OFF automatically
Emission ON/OFF by user via interfaces
(→  29)

Current (p <7.2×10-6 mbar) ≈20 mA
Control input signal 0 V/+24 VDC, active high

(→  19, 20)

(control via RS232C →  30)
Duration <3 min., followed by automatic stop
In degas mode, the BPG402-Sx gauges keep supplying pressure readings, the

tolerances of which can be higher than during normal operation.
Degas acts only upon the active filament.

Output signal (measuring signal) 0 … +10 VDC
Measuring range +0.774 … +10 V

(5×10

-10

… 1000 mbar)

Relationship voltage-pressure logarithmic, 0.75 V/decade

(

→ Appendix A)

Error signal (→  42)

EEPROM error
Hot cathode error
Pirani error

Minimum load impedance

BPG402-Sx

≈+0.1 VDC

≈+0.3 VDC

≈+0.5 VDC

10 kΩ

42 kΩ resistor between Pin 10 and Pin 5

(sensor cable)

8

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Switching functions

RS232C interface

DeviceNet interface
(BPG402-SD)

BPG402-S, -SL
BPG402-SD, -SP
Adjustment range

1 ("SETPOINT")
2 ("SETPOINT A, B")

-9

mbar … 100 mbar

1×10
Setpoints adjustable via potentiometers,

one floating, normally open relay contact
per setpoint (→  19, 20, 37).

(Adjusting the setpoints via field bus

→ corresponding bus section)
Hysteresis 10% of the threshold value
Relaiskontaktbelastung

Data rate
Data format

Connections (sensor cable connector)

TxD (Transmit Data)
RxD (Receive Data)
GND

≤30 VDC, ≤0.5 ADC

9600 Baud
binary

8 data bits
one stop bit
no parity bit
no handshake

Pin 13
Pin 14
Pin 5

Function and communication protocol of the RS232C interface →  30

Fieldbus name DeviceNet
Standard applied
Communication protocol, data format
Interface, physical CAN bus

Data rate
(adjustable via "RATE" switch)

→  [6]

→  [1], [4]

125 kBaud

250 kBaud

500 kBaud (default)

"P" (125 kBaud, 250 kBaud, 500 kBaud

programmable via DeviceNet)

(→  [1])
Node address (MAC ID)

(Adjustable via "ADDRESS", "MSD",
"LSD" switches)

0 … 63

(default = 63

dec

dec

)
"P" (0 … 63 programmable via
DeviceNet, →  [1])

DeviceNet connector Micro-Style, 5 pins, male

Cable shielded, special DeviceNet cable,

5 conductors (→  21 and  [4])

Cable length, system wiring according to DeviceNet specifications

(→  [6], [4])

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Profibus interface
(BPG402-SP)

Display (BPG402-S only)

Power supply

Fieldbus name Profibus
Standard applied
Communication protocol, data format
Interface, physical RS485

Data rate
Node address

Local
(Adjustable via hexadecimal
"ADDRESS", "MSD", "LSD"
switches)

Default setting
Via Profibus

("ADDRESS" switches set to >7D
(>125

dec

))

→  [7]
→  [2], [7]

≤12 MBaud (→  [2])

00 … 7D
5C

hex

hex

hex

00 … 7D

hex

(0 … 125

(0 … 125

dec

dec

)

)

Profibus connection D-Sub, 9 pins, female

Cable shielded, special Profibus cable

(→  22 and  [5])

Cable length, system wiring according to Profibus specifications

(→  [7], [5])

Display panel

Dimensions
Pressure units

Selecting the pressure unit

LCD matrix, 32×16 pixels,
with background illumination

17.0 mm × 12 mm
mbar (default), Torr, Pa

via RS232C (→  30)

DANGER

The gauge must only be connected to power supplies, instruments or
control devices that conform to the requirements of a grounded extra­low voltage (SELV). The connection to the gauge has to be fused
(INFICON-controllers fulfill these requirements).

Supply voltage at the gauge +24 VDC (+20 … +28 VDC) 1)

Power consumption

Standard
Degas
Emission start (<200 ms)

ripple max. 2 V

≤0.5 A
≤0.8 A
≤1.4 A

pp

Fuse necessary 1.25 AT

((INFICON controllers fulfill these
requirements)

Power consumption

BPG402-S, -SL
BPG402-SD
BPG402-SP

≤18 W
≤18 W
≤20 W

The BPG402-SD requires an additional, separate power supply for the

Supply voltage at the DeviceNet

Power consumption

DeviceNet interface (→  21).

connector (Pin 2 and Pin 3)

+24 VDC (+11 … +25 VDC)
≤2 W

The gauge is protected against reversed polarity of the supply voltage.

10

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Electrical connection

Materials used

Ambiance

For reasons of compatibility, the expression "sensor cable" is used for all

BPG402 versions in this document, although the pressure reading of the
gauges with fieldbus interface (BPG402-SD and BPG402-SP) is

Electrical connection

normally transmitted via the corresponding bus.

BPG402-S, -SL
BPG402-SD, -SP

D-Sub,15 pins, male

→  19
→  20

Sensor cable shielded, number of conductors de-

pending on the functions used,
max. 15 conductors plus shielding

1)

Cable length (supply voltage 24 VDC

Analog and fieldbus operation

For operation with RS232C interface

Materials exposed to vacuum

Housing, supports, screens
Feedthroughs
Insulator
Cathode
Cathode holder
Pirani element

Internal volume

DN 25 ISO-KF
DN 40 CF-R

)

≤35 m, 0.25 mm²/conductor
≤50 m, 0.34 mm²/conductor
≤100 m, 1.0 mm²/conductor

≤30 m

stainless steel
NiFe, nickel plated
glass
iridium, yttrium oxide (Y
molybdenum, platinum
tungsten, copper

3

≈24 cm

3

≈34 cm

2O3

)

Pressure max. 2 bar (absolute)

Admissible temperatures

Storage
Operation
Bakeout

Long tube

Relative humidity

Year's mean
During 60 days

-20 … 170 °C
0 … 150 °C

2)

+ 80 °C
+150 °C

2)

≤65 (no condensation)
85% (no condensation)

Use indoors only

altitude up to 2000 m NN
Mounting orientation any
Type of protection IP 30

1)

Measured at gauge connector (consider the voltage drop as function of the sensor cable

length).

2)

Flange temperature, electronics unit removed, horizontally mounted.

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Dimensions [mm]

4-40UNC 2B

4-40UNC 2B

DN 25 ISO-KF

DN 40 CF-R

4-40UNC 2B

Gauges with DeviceNet connector

are 14 mm longer.

DN 40 CF-R

Weight

353-570, 353-572
353-571, 353-573
353-578

≈450 g
≈710 g
≈917 g

353-574, 353-576

12

353-575, 353-577

≈490 g
≈750 g

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3 Installation

3.1 Vacuum Connection

DANGER: overpressure in the vacuum system >1 bar
Injury caused by released parts and harm caused by escaping process

gases can result if clamps are opened while the vacuum system is
pressurized.

Do not open any clamps while the vacuum system is pressurized. Use
the type of clamps which are suited to overpressure.

The gauge must be electrically connected to the grounded vacuum
chamber. This connection must conform to the requirements of a pro­tective connection according to EN 61010:

• CF connections fulfill this requirement

• For gauges with a KF vacuum connection, use a conductive me-

tallic clamping ring.

DANGER

DANGER

Caution: vacuum component
Dirt and damages impair the function of the vacuum component.
When handling vacuum components, take appropriate measures to

ensure cleanliness and prevent damages.

Caution: dirt sensitive area
Touching the product or parts thereof with bare hands increases the

desorption rate.
Always wear clean, lint-free gloves and use clean tools when working

in this area.

The gauge may be mounted in any orientation. To keep condensates

and particles from getting into the measuring chamber, preferably
choose a horizontal to upright position. See dimensional drawing for
space requirements (→  12).

The gauge is supplied with a built-in grid. For potentially contaminating
applications and to protect the electrodes against light and fast charged
particles, installation (→  15) of the optional baffle is recommended
(→  45).

Caution

Caution

When installing the gauge, make sure that the area around the con-

nector is accessible for the tools required for adjustment while the gauge
is mounted (→  38, 41).

When installing the gauge, allow for installing/deinstalling the connectors
and accommodation of cable loops.

If you are using a gauge with display, make sure easy reading of the
display is possible.

Vacuum connection free of grease.

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Procedure

3.1.1 Removing and Installing
the Electronics Unit

Required tools / material

Removing the electronics unit

Remove the protective lid and install the gauge to the vacuum system.

Seal with centering ring

Protective lid

Clamp

• Allen wrench, AF 2.5

(keep it)

 Unscrew the hexagon socket set screw (1) on the side of the electronics

unit (2).

1

2

 Remove the electronics unit without twisting it.

14

tina46e1-a (2010-03) BPG402.om

Installing the electronics unit

 Place the electronics unit (2) on the sensor (3) (be careful to correctly align

the pins and notch (4)).

3.1.2 Using the Optional Baffle

Precondition

Required tools / material

Installation

4

3

2

 Slide the electronics unit in to the mechanical stop and lock it with the hexa-

gon socket set screw.

In severely contaminating processes and to protect measurement electrodes opti­cally against light and fast charged particles, replacement of the built-in grid by the
optional baffle (→  45) is recommended.

Gauge deinstalled ("Deinstallation" →  39).

• Baffle (→  45)

• Pointed tweezers

• Pin (e.g. pencil)

• Screwdriver No 1

 Carefully remove the grid with tweezers.

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 Carefully place the baffle onto the sensor opening.

 Using a pin, press the baffle down in the center until it catches.

Deinstallation

Carefully remove the baffle with the screwdriver.

16

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3.2 Electrical Connection

3.2.1 Use With INFICON
VGC40x Vacuum Gauge
Controller

Required material

Procedure

If the gauge is used with an INFICON VGC40x controller, a corresponding sensor
cable is required (→ [3]). The sensor cable permits supplying the gauge with
power, transmitting measurement values and gauge statuses, and making pa­rameter settings.

Caution

Caution: data transmission errors
If the gauge is operated with the INFICON VGC40x Vacuum Gauge

Controller (RS232C) and a fieldbus interface at the same time, data
transmission errors may occur.

The gauge must not be operated with an INFICON VGC40x controller
and DeviceNet or Profibus at the same time.

• Sensor cable (→  [3]), INFICON sales literature)

 Plug the sensor connector into the gauge and secure it with the locking

screws.

3.2.2 Use With Other
Controllers

 Connect the other end of the sensor cable to the INFICON controller and

secure it.

The gauge can also be operated with other controllers.
Especially the fieldbus versions BPG402-SD (DeviceNet) and BPG402-SP

(Profibus) are usually operated as part of a network, controlled by a master or bus
controller. In such cases, the control system has to be operated with the appropri­ate software and communication protocol (→  [1], [2]).

tina46e1-a (2010-03) BPG402.om 17

3.2.2.1 Making an Individual
Sensor Cable

Cable type

Procedure

For reasons of compatibility, the expression "sensor cable" is used for all

BPG402 versions in this document, although the pressure reading of the
gauges with fieldbus interface (BPG402-SD or BPG402-SP) is normally
transmitted via DeviceNet or Profibus.

The sensor cable is required for supplying all BPG402 types with power.
It also permits access to the relay contacts of the switching functions
(→  19, 20).

The application and length of the sensor cable have to be considered when deter­mining the number and cross sections of the conductors (→  11).

 Open the cable connector (D-Sub, 15 pins, female).
 Prepare the cable and solder/crimp it to the connector as indicated in the

diagram of the gauge used:

18

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Sensor cable connection
BPG402-S, -SL

Threshold value, SP

( )

-

1)

3

SP

Filament status

TxD

4
1

11

9

13

RS232

12

14

7

6

2

Degas

-

RxD

Degas

Measuring

signal

1.25 AT

42 k

V

S

Ω

Common (power GND 24V supply)
Ground (housing, vacuum connection)

10

15

8

Ident.

5

9

24V

-

-

1

D-Sub,15 pins,

female,

soldering side

Electrical connection

15

8

Pin 1 Relay switching function, common contact
Pin 2 Measuring signal output 0 … +10 V

1)

Pin 3 Threshold (setpoint)

0 … +10 V
Pin 4 Relay switching function, n.o. contact
Pin 5 Supply common 0 V
Pin 6 Not connected internally
Pin 7 Degas (active high) 0 V/+24 V
Pin 8 Supply (V
Pin 9 Relay filament status, common contact

) +24 V

s

2)

Pin 10 Gauge identification

2)

Pin 11 Relay filament status, n.o. contact
Pin 12 Measuring signal common
Pin 13 RS232C, TxD
Pin 14 RS232C, RxD
Pin 15 Do not connect

1)

Do not connect pin 3 for normal operation of the gauge. This pin is reserved for

adjustment of the setpoint potentiometers (→  38).

2)

→ table on  28.

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Sensor cable connection
BPG402-SD, -SP

Threshold value

TxD

RxD

SP A

SP B

( )

SP A
SP B

-

1)

3
6

4
1

11

9

13

RS232

14

Degas

Measuring

signal

12

7

6
2

Degas

-

1.25 AT

42 k

V

S

Ω

Common (power GND 24V supply)
Ground (housing, vacuum connection)

10

15

8

Ident.

5

9

24V

-

-

1

D-Sub,15 pins,

female,

soldering side

Electrical connection

15

8

Pin 1 Relay switching function A, common contact
Pin 2 Measuring signal output 0 … +10 V

1)

Pin 3 Threshold (setpoint) A

0 … +10 V
Pin 4 Relay switching function A, n.o. contact
Pin 5 Supply common 0 V

1)

Pin 6 Threshold (setpoint) B

0 … +10 V
Pin 7 Degas (active high) 0 V/+24 V
Pin 8 Supply (V

) +24 V

s

Pin 9 Relay switching function B, common contact
Pin 10 Gauge identification
Pin 11 Relay switching function B, n.o. contact
Pin 12 Measuring signal common
Pin 13 RS232C, TxD
Pin 14 RS232C, RxD
Pin 15 Do not connect

1)

Do not connect pin 3 and pin 6 for normal operation of the gauge. These pins

are reserved for adjustment of the setpoint potentiometers (→  38).

WARNING

The supply common (Pin 5) and the shielding must be connected at
the supply unit with protective ground.

Incorrect connection, incorrect polarity or inadmissible supply voltages

20

can damage the gauge.

tina46e1-a (2010-03) BPG402.om

For cable lengths up to 5 m (0.34 mm2 conductor cross-section) the out-

put signal can be measured directly between the positive signal output
(Pin 2) and supply common (Pin 5). At greater cable lengths, differential
measurement between signal output (Pin 2) and signal common (Pin 12)
is recommended.

 Reassemble the cable connector.
 On the other cable end, terminate the cable according to the requirements

of the gauge controller you are using.

Plug the sensor connector into



the gauge and secure it with the
locking screws.

3.2.2.2 Making a DeviceNet
Interface Cable

(BPG402-SD)

Cable type

Procedure

 Connect the other end of the sensor cable to the connector of the instru-

ment or gauge controller you are using.

For operating BPG402-SD via DeviceNet, an interface cable conforming to the
DeviceNet standard is required.
If no such cable is available, make one according to the following indications.

A shielded special 5 conductor cable conforming to the DeviceNet standard has to
be used (→  [4], [6]).

 Make the DeviceNet cable according to the following indications.

Pin 1 Drain
Pin 2 Supply (DeviceNet interface only) +24 VDC
Pin 3 Supply common (DeviceNet interface only) GND
Pin 4 CAN_H
Pin 5 CAN_L

1

5

3

Micro-Style, 5 pins,
(DeviceNet)

42

female, soldering side

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 Plug the DeviceNet (and sensor) cable connector into the gauge.

3.2.2.3 Making a Profibus
Interface Cable

(BPG402-SP)

Cable type

Procedure

Sensor cable

DeviceNet cable

 Lock the DeviceNet (and sensor) cable connector.

For operating BPG402-SP via Profibus, an interface cable conforming to the
Profibus standard is required.

If no such cable is available, make one according to the following indications.

Only a cable that is suited to Profibus operation may be used (→  [5], [7]).

 Make the Profibus interface cable according to the following indications:

1 5

D-Sub, 9 pins
male, soldering side

6 9

Pin 1 Do not connect
Pin 2 Do not connect
Pin 3 RxD/TxD-P
Pin 4 CNTR-P
Pin 5 DGND
Pin 6 VP

1)

2)

2)

Pin 7 Do not connect
Pin 8 RxD/TxD-N
Pin 9 Do not connect

1)

Only to be connected if an optical link module is used.

2)

Only required as line termination for devices at both ends of bus system

(→  [5]).

22

tina46e1-a (2010-03) BPG402.om

3.2.3 Using the Optional
Power Supply
(With RS232C Line)

Technical data

Wiring diagram

 Plug the Profibus (and sensor) cable connector into the gauge.

Sensor cable

Profibus cable

 Lock the Profibus cable (and sensor cable) connector.

The optional 24 VDC power supply (→  45) allows RS232C operation of the
BPG402-Sx gauge with any suitable instrument or control device.

The instrument or control device needs to be equipped with a software that sup­ports the RS232C protocol of the gauge (→  30).

Mains connection

Mains voltage 90 … 250 VAC, 50 … 60 Hz
Mains cable 1.8 meter (Schuko DIN and U.S. con-

PE

nectors)

+24 V

GND

DC

AC

8
7
6

RS232C

4

D-Sub, 9 pins

5
2
3

L

Mains

N

90 ... 250 VAC

PE

50 ... 60 Hz

Output (operating voltage of gauge)

Voltage 21 … 27 VDC, set to 24 VDC
Current Max. 1.5 A

Gauge connection

Connector D-Sub, 15 pins, female
24 VDC cable 5 m, black

Connection of the instrument or
control device

RS232C connection D-Sub, 9 pins, female
Cable 5 m, black, 3 conductors, shielded

BPG402-Sx

D-Sub,
15 pins

5
13
14

8
15

tina46e1-a (2010-03) BPG402.om 23

Connecting the power supply

 Connect the power supply to the gauge and lock the connector with the

screws.

 Connect the RS232C line to the instrument or control device and lock the

connector with the screws.

RS232C

Power supply

BPG402-Sx

 Connect the power supply to the mains.

PC

Mains

24

tina46e1-a (2010-03) BPG402.om

4 Operation

4.1 Measuring Principle,
Measuring Behavior

Bayard-Alpert

The BPG402-Sx vacuum gauges consist of two separate measuring systems (hot
cathode Bayard-Alpert (BA) and Pirani).

The hot cathode measuring system uses an electrode system according to Bayard­Alpert which is designed for a low X-ray limit.

The measuring principle of this measuring system is based on gas ionization.
Electrons emitted by the operating filament (F1 or F2, → below) ionize a number of
molecules proportional to the pressure in the measuring chamber. The ion collector
(IC) collects the produced ion current I

+

and feeds it to the electrometer amplifier of
the measurement instrument. The ion current is dependent upon the emission cur­rent I

, the gas type, and the gas pressure p according to the following relationship:

e

I+ = Ie × p × C

Factor C represents the sensitivity of the gauge head. It is generally specified for
N

.

2

The lower measurement limit is 5×10
To usefully cover the whole range of 5×10

-10

mbar (gauge metal sealed).

-10

mbar … 10-2 mbar, a low emission
current is used in the high pressure range (fine vacuum) and a high emission cur­rent is used in the low pressure range (high vacuum). The switching of the emis­sion current takes place at decreasing pressure at approx. 7.2×10
creasing pressure at approx. 3.0×10
BPG402-Sx can temporarily (<2 s) deviate from the specified accuracy.

-5

mbar. At the switching threshold, the

-6

mbar, at in-

Pirani

IC

F 1

EC

F 2

FS

+– +–

200V40V

(Degas 2.5V) (Degas 250V)

Diagram of the Bayard-Alpert
measuring system

F1/F2 hot cathodes (filaments)

IC ion collector

F 1

EC

F 2

EC anode (electron collector)
FS filament selector switch

IC

Within certain limits, the thermal conductibility of gases is pressure dependent. This
physical phenomenon is used for pressure measurement in the thermal
conductivity vacuum meter according to Pirani. A self-adjusting bridge is used as
measuring circuit (→ schematic). A thin tungsten wire forms the sensor element.
Wire resistance and thus temperature are kept constant through a suitable control
circuit. The electric power supplied to the wire is a measure for the thermal con­ductance and thus the gas pressure. The basic principle of the self-adjusting bridge
circuit is shown in the following schematic:

tina46e1-a (2010-03) BPG402.om 25

Schematic

Measuring range

Gas type dependence

Dual filament feature

V

B

Pirani sensor

The bridge voltage V

is a measure for the gas pressure and is further processed

B

electronically (linearization, conversion).

The BPG402 -Sx gauges continuously cover the measuring range

-10

5×10

mbar … 1000 mbar.

• The Pirani constantly monitors the pressure.

• The hot cathode (controlled by the Pirani) is activated only at pressures

<2.4×10

-2

mbar.

If the measured pressure is higher than the switching threshold, the hot cathode is
switched off and the Pirani measurement value is output.

If the Pirani measurement drops below the switching threshold (p = 2.4×10-2 mbar),
the hot cathode is switched on. After heating up, the measured value of the hot
cathode is fed to the output. In the overlapping range of 5.5×10

-3

… 2.0×10-2 mbar,

the output signal is generated from both measurements.
Pressure rising over the switching threshold (p = 3.2×10-2 mbar) causes the hot

cathode to be switched off. The Pirani measurement value is output.

The output signal is gas type dependent. The characteristic curves are accurate for
dry air, N

and O2. They can be mathematically converted for other gases

2

(→ Appendix B).

BPG402-Sx sensors are equipped with two identical filaments. They are perma­nently monitored by the gauge electronics. In case of a filament breakage, the
gauge will immediately react and switch over to the second (undamaged) filament.
During the change over procedure, the last valid pressure value before filament
failure will be output. As soon as the second filament is operating and the emission
parameters have settled (t <4s), the measuring circuit resumes operation. A "Hot
Cathode Warning" is generated during this switch over cycle. The filament status
indicator LED on the gauge will display the incident (blinking green, →  28). The
filament status can also be read via the RS232C or field bus interfaces (→  30,
 [1] and [2]). Additionally, the BPG402-S offers a relay contact "Filament status"
on the sensor cable connector (→  19). In case of two broken filaments, a "Hot
Cathode Error" is generated. Again, this status can be read via the interfaces
(→  30,  [1] and [2]) and is also displayed by a red filament status indicator
LED on the gauge (→  28). In this case, the sensor has to be replaced (→  44).

At the beginning of every "Emission ON" cycle, the gauge alternates between fila­ments in order to age both filaments evenly. However, filament selection can be
commanded via the interfaces (→  28, 30,  [1] and [2]).

INFICON recommends the replacement of the sensor as soon as the first filament
failure has been detected. The replacement can be carried out during an appropri­ate off time such as the completion of a process or a planned maintenance brake.

26

tina46e1-a (2010-03) BPG402.om

4.2 Operational Principle of
the Gauge

4.3 Putting the Gauge Into
Operation

4.4 Degas

Contamination

The analog measuring signals of the Bayard-Alpert and Pirani sensors are con­verted into a digital form by a micro-controller and subsequently converted to a
value representing the measured total pressure. After further processing this value
is available as analog measurement signal (0 … +10 V) at the output (sensor cable
connector Pin 2 and Pin 12). The maximum output signal is internally limited to
+10 V (atmosphere). The measured value can be read as digital value through the
RS232C interface (Pins 13, 14, 5) (→  30). Gauges with a display show the value
as pressure. The default setting of the displayed pressure unit is mbar. It can be
modified via the RS232C interface (→  30).

In addition to converting the output signal, the micro controller's functions include
monitoring of the emission, filament status, calculation of the total pressure based
on the measurements of the two sensors, and communication via RS232C inter­face.

When the operating voltage is supplied (→ Technical Data), the output signal is
available between Pin 2 (+) and Pin 12 (–) of the sensor cable connector
(Relationship Output Signal – Pressure → Appendix A).

Allow for a stabilizing time of approx. 10 min. Once the gauge has been switched
on, permanently leave it on irrespective of the pressure.

Communication via the digital interfaces is described in separate sections.

Gauge failures due to contamination, as well as expendable parts

(filament), are not covered by the warranty.

Deposits on the electrode system of the Bayard-Alpert gauge can lead to unstable
measurement readings.

The degas process allows in-situ cleaning of the electrode system by heating the
electron collector grid to approx. 700 °C by electron bombardment.

Depending on the application, this function can be activated by the system control
via one of the gauges digital interfaces. The gauge automatically terminates the
degas process after 3 minutes, if it has not been stopped before.

The degas process should be run at pressures below 7.2×10-6 mbar

(emission current 5 mA).

For a repeated degas process, the control signal first has to change from ON
(+24 V) to OFF (0 V), to then start degas again with a new ON (+24 V) command. It
is recommended that the degas signal be set to OFF again by the system control
after 3 minutes of degassing, to achieve an unambiguous operating status.

A new degas cycle can only be started after a waiting time of

30 minutes.

Degas acts only upon the active filament.

tina46e1-a (2010-03) BPG402.om 27

4.5 Filament Status

4.5.1 Filament Status Indicator

The status of the dual filament hot cathode is indicated by a LED on top of the
gauge.

Filament status indi cator LED

4.5.2 Filament Status Relay

(Only BPG402-S, SL)

4.5.3 Filament Status via
Interface

4.6 Filament Control Mode

Filament status Emission Filament status

indicator

– off dark
Both filaments O.K. on green
One filament broken on green, flashing
Both filaments broken on red

INFICON recommends the replacement of the sensor as soon as the

first filament failure has been detected (replacing the sensor →  44).

The BPG402-S, SL features a "Filament status" relay contact available at the
sensor cable connector:

Filament status Relay contact

(→ diagram  19)
Both filaments O.K. closed
One filament broken open
Both filaments broken open

The filament status can be read via the serial interfaces:
Gauge Interface Detailed information

BPG402-Sx (all versions) RS232C
BPG402-SD DeviceNet
BPG402-SP Profibus

→  31
→  [1]
→  [2]

In automatic mode (AUTO) (default) the gauge automatically alternates between
filaments in order to age both filaments evenly. However, in manual mode (MAN),
filament selection can be commanded via the interfaces.

The filament control mode can only be changed via the interfaces

(→  30,  [1] and [2]).

28

tina46e1-a (2010-03) BPG402.om

4.7 Emission Control Mode

General

The emission control mode function defines the rules by which the emission of the
gauge is switched on and off.

The manual mode feature has a positive effect on gauge live time, mainly in
process situations where the process chamber has to be vented frequently.

Emission Control Mode Description

4.8 Display (BPG402-S)

Pressure Display

• Automatic (AUTO)

By default, the automatic mode is active and the emis­sion is switched on and off automatically by the gauge.
However, the emission will only be switched on if the
pressure falls below "Switching on pressure" (→  8).
If the pressure rises above the "Switching off pressure"
(→  8), the emission is switched off. However, the
user can switch off the emission any time via the
interfaces (→ below).

• Manual (MAN)

In manual mode, the emission can be switched on and
off by the user. However, switching on the emission is
only possible if the pressure is below "Switching on
pressure" (→  8). If the pressure rises above the
"Switching off pressure" (→  8) while the emission is
on, the emission will be switched off by the gauge.

The emission control mode parameter is only accessible via the serial

interfaces and described in the respective sections (→  30,  [1] and
[2]).

The gauges with part number

353-572 and
353-573

have a built-in two-line display with an LCD matrix of 32×16 pixels. The first line
shows the pressure, the second line the pressure unit, the function and possible
errors. The background illumination is usually green, in the event of an error, it
changes to red. The pressure is displayed in mbar (default), Torr or Pa. The pres­sure unit can be changed via RS232C interface (→  30).

Pressure reading

Pressure unit

Function Display

Function display

(none)

Pirani operation

E Emission 25 μA

. Emission 5 mA

E

tina46e1-a (2010-03) BPG402.om 29

D Degas

Error Display

No error
(green background illumination)

Pirani sensor error
(red background illumination)

4.9 RS232C Interface

Bayard-Alpert sensor error
(red background illumination)

EEPROM error
(red background illumination)

Internal data communication failure
(red background illumination)

What to do in case of problems →  42.

The built-in RS232C interface (all BPG402 versions) allows transmission of digital
measurement data and instrument conditions as well as the setting of instrument
parameters.

Caution

Caution: data transmission errors
If the gauge is operated with the RS232C interface and a fieldbus in-

terface at the same time, data transmission errors may occur.
The gauge must not be operated with the RS232C interface and

4.9.1 Description of the
Functions

Operational parameters

The interface works in duplex mode. A nine byte string is sent continuously without
a request approx. every 6 ms.

Commands are transmitted to the gauge in a five byte input (receive) string.

• Data rate

• Byte

• Handshake

• Parity bit

30

DeviceNet or Profibus at the same time.

9600 Baud (set value)
8 data bits

1 stop bit
no
none

tina46e1-a (2010-03) BPG402.om

Electrical connections

4.9.1.1 Output String (Transmit

Format of the output string

Synchronization

Status byte

• TxD

• RxD

• GND

Pin 13
Pin 14
Pin 5

(Sensor cable connector)

)

The complete output string (frame) is nine bytes (byte 0 … 8). The data string is
seven bytes (byte 1 … 7).

Byte No Function Value Comment

0 Length of data string 7 set value
1 Page number 5 hot cathode gauges
2 Status
3 Error
4 Measurement high byte 0 … 255
5 Measurement low byte 0 … 255
6 Software version 0 … 255

→ Status byte
→ Error byte
→ Calculation of pressure value
→ Calculation of pressure value
→ Software version

7 Sensor type 12 for BPG402-Sx
8 Check sum 0 … 255

Synchronization of the master is achieved by testing three bytes:

→ Synchronization

Byte No Function Value Comment

0 Length of data string 7 set value
1 Page number 5 hot cathode gauges
8 Check sum of bytes No 1 … 7 0 … 255 low byte of

1)

High order bytes are ignored in the check sum.

check sum

1)

Bit 1 Bit 0 Definition

0 0 emission off
0 1

emission 25 μA
1 0 emission 5 mA
1 1 degas

Bit 2 Definition

x not used

Bit 3 Definition

0 ⇔ 1

toggle bit, changes with every

string received correctly

Bit 5 Bit 4 Definition

0 0 current pressure unit mbar
0 1 current pressure unit Torr
1 0 current pressure unit Pa

Bit 6 Definition

0 filament 1 active
1 filament 2 active

Bit 7 Definition

x not used

tina46e1-a (2010-03) BPG402.om 31

Error byte

Software version

Calculation of the pressure
value

Example

Bit 7 Bit 3 Bit 1 Bit 0 Definition

x x x x not used

Bit 6 Bit 5 Bit 4 Bit 2 Definition

x x x 1 Pirani error
x x 1 x hot cathode error 2)
x 1 x x hot cathode warning 3)
1 x x x electronics error / EEPROM error

2)

Both filaments broken

3)

One filament broken

The software version of the gauge can be calculated from the value of byte 6 of the
transmitted string according to the following rule:

Version No = Value

(Example: According to the above formula, Value

Byte 6

/ 20

of 32 means software ver-

Byte 6

sion 1.6)

The pressure can be calculated from bytes 4 and 5 of the transmitted string. De­pending on the currently selected pressure unit (→ byte 2, bits 4 and 5), the ap­propriate rule must be applied.

As result, the pressure value results in the usual decimal format.

((high byte × 256 + low byte) / 4000 - 12.5)

= 10

p

mbar

p

= 10

Torr

pPa = 10

The example is based on the following output string:

((high byte × 256 + low byte) / 4000 - 12.625)

((high byte × 256 + low byte) / 4000 - 10.5)

Byte No 0 1 2 3 4 5 6 7 8
Value 7 5 0 0 242 48 20 12 71

The instrument or controller (receiver) interprets this string as follows:

Byte No Function Value Comment

0 Length of

data string

7

set value
1 Page number 5 hot cathode gauge
2 Status 0

emission = off

pressure unit = mbar

filament 1 active
3 Error 0

Measurement
4
5

High byte
Low byte

6 Software version 20

no error

calculation of the pressure:

242

48

((242 × 256 + 48) / 4000 - 12.5)

p = 10
software version = 20 / 20 = 1.0

= 1000 mbar

7 Sensor type 12 BPG402-Sx
8 Check sum 71

5 + 0 + 0 + 242 + 48 + 20 + 12 =

01 47

327

dec

hex

High order byte is ignored ⇒
Check sum = 47

hex

71

dec

32

tina46e1-a (2010-03) BPG402.om

4.9.1.2 Input String (Receive)

Format of the input string

Admissible input strings

For transmission of the commands to the gauge, a string (frame) of five bytes is
sent (without <CR>). Byte 1 … 3 form the data string.

Byte no Function Value Comment

0 Length of data string 3 set value
1 Data
2 Data
3 Data
4 Check sum

4)

High order bytes are ignored in the check sum.

(from bytes No 1 … 3) 0 … 255

→ admissible input strings
→ admissible input strings
→ admissible input strings

(low byte of sum)

4)

For commands to the gauge, the following strings are defined (values in decimal
notation):

Command Byte No
0 1 2 3 4 5)
Set the unit mbar in the display 3 16 142 0 158
Set the unit Torr in the display 3 16 142 1 159
Set the unit Pa in the display 3 16 142 2 160
Power-failure-safe storage of current unit 3 32 2 – 34

Switch degas on
(switched off automatically after 3 minutes)

3 16 196 1 213

Switch degas off (before 3 minutes) 3 16 196 0 212
Set Emission Control Mode to AUTO 6) 3 16 138 1 155

Set Emission Control Mode to MAN 6) 3 16 138 0 154
Power-failure-safe storage of the

Emission Control Mode

6)

3 32 1 – 33

Switch emission on 3 64 16 1 81
Switch emission off 3 64 16 0 80

Set Filament Control Mode to AUTO 7) 3 16 211 0 227
Set Filament Control Mode to MAN 7) 3 16 211 1 228
Power-failure-safe storage of the

Filament Control Mode

7)

3 32 13 – 45

Select filament 1 8) 3 16 210 0 226
Select filament 2 8) 3 16 210 1 227
Power-failure-safe storage of selected filament 8) 3 32 12 – 44
Read filament status 3 0 212 – 212

Read software version 3 0 209 – 209
Reset 3 64 0 0 64

5)

Only low order byte of sum (high order byte is ignored).

6)

Defines the Emission Control Mode (→  29):

AUTO = emission on/off automatically controlled by the gauge
MAN = emission on/off controlled via interfaces.

7)

Defines the Filament Control Mode (→  29):

AUTO = Selection of filament automatically controlled by the gauge
MAN = Selection of filament controlled via interfaces.

8)

The "Select filament x" command can be sent any time but is only executed if

the gauge is in the "Emission OFF" state.

tina46e1-a (2010-03) BPG402.om 33

4.10 DeviceNet Interface

(BPG402-SD)

4.10.1 Description of the
Functions

4.10.2 Operating Parameters

4.10.2.1 Operating Software

4.10.2.2 Node Address Setting

This interface allows operation of BPG402-SD with part number

353-576 and
353-577

in connection with other devices that are suited for DeviceNet operation. The
physical interface and communication firmware of BPG402-SD comply with the
DeviceNet standard (→  [4], [6]).

Two adjustable switching functions are integrated in BPG402-SD. The corre­sponding relay contacts are available at the sensor cable connector (→  8, 20,

37).
The basic sensor and sensor electronics of all BPG402 gauges are identical.

Caution

Caution: data transmission errors
If the gauge is operated via RS232C interface and DeviceNet interface

at the same time, data transmission errors may occur.
The gauge must not be operated via RS232C interface and DeviceNet

Via this interface, the following and further data are exchanged in the standardized
DeviceNet protocol (→  [1]):

• Pressure reading

• Pressure unit (Torr, mbar, Pa)

• Degas function

• Gauge adjustment

• Status and error messages

• Status of the switching functions

As the DeviceNet protocol is highly complex, the parameters and programming of
BPG402-SD are described in detail in the separate Communication Protocol
(→  [1]).

Before the gauge is put into operation, it has to be configured for DeviceNet op­eration. A configuration tool and the device specific EDS file (Electronic Data
Sheet) are required for this purpose. The EDS file can be downloaded via internet
(→  [3]).

For unambiguous identification of the gauge in a DeviceNet environment, a node
address is required. The node address setting is made on the gauge or pro­grammed via DeviceNet.

interface at the same time.

Set the node address (0 … 63

) via the "ADDRESS" "MSD"

dec

and "LSD" switches. The node address is polled by the firmware
when the gauge is switched on. If the setting deviates from the
stored value, the new value is taken over into the NVRAM. If a
setting higher than 63 is made, the previous node address set­ting remains valid.

Default address setting is 63

dec

.

If the „MSD“ switch is in the "P" position, the node address is
programmable via DeviceNet (→  [1]).

34

tina46e1-a (2010-03) BPG402.om

4.10.2.3 Data Rate Setting

4.10.3 Status Indicators

"STATUS MOD"
(gauge status):

"STATUS NET"
(network status):

Electrical connections

The admissible data rate depends on a number of factors such as system pa­rameters and cable length (→  [4], [6]). It can be set on the gauge or pro-
grammed via DeviceNet.

By means of the "RATE" switch, the data rate can be set to 125
("1"), 250 ("2") or 500 kBaud ("5").

Default data rate setting is 500 kBaud.
If the switch is in any of the "P" positions, the data rate is pro-

grammable via DeviceNet (→  [1]).

Two LEDs on the gauge inform on the gauge status and the current DeviceNet
status.

LED Description

Dark no supply

Red/green,

self test

flashing

Green normal operation

Red non recoverable error

LED Description

Dark gauge not online:

− self test not yet concluded

− no supply, → "STATUS MOD" LED

Green,

flashing

gauge online but no communication:

− self test concluded but no communication to other nodes
established

− gauge not assigned to any master

Green gauge online; necessary connections established

Red, flashing one or several input / output connections in "time out" status

Red communication error. The gauge has detected an error that im-

pedes communication via the network (e.g. two identical node ad­dresses (MAC IC) or "Bus-off")

The gauge is connected to the DeviceNet system via the 5-pin DeviceNet con­nector (→  21).

tina46e1-a (2010-03) BPG402.om 35

4.11 Profibus Interface

(BPG402-SP)

4.11.1 Description of the
Functions

4.11.2 Operating Parameters

4.11.2.1 Operating Software

4.11.2.2 Node Address Setting

Electrical connections

This interface allows operation of BPG402-SP with part number

353-574 and
353-575

in connection with other devices that are suited for Profibus operation. The physical
interface and communication firmware of BPG402-SP comply with the Profibus
standard (→  [5], [7].

Two adjustable switching functions are integrated in the BPG402-SP. The corre­sponding relay contacts are available at the sensor cable connector (→  8, 20,

37).
The basic sensor and sensor electronics of all BPG402 gauges are identical.

Caution

Caution: data transmission errors
If the gauge is operated via RS232C interface and Profibus interface at

the same time, data transmission errors may occur.
The gauge must not be operated via RS232C interface and Profibus

Via this interface, the following and further data are exchanged in the standardized
Profibus protocol (→  [2]):

• Pressure reading

• Pressure unit (Torr, mbar, Pa)

• Degas function

• Gauge adjustment

• Status and error messages

• Status of the switching functions

As the DeviceNet protocol is highly complex, the parameters and programming of
BPG402-SP are described in detail in the separate Communication Protocol
(→  [2]).

For operating the gauge via Profibus, prior installation of the BPG402-SP specific
GSD file is required on the bus master side. This file can be downloaded via inter­net (→  [3]).

For unambiguous identification of the gauge in a Profibus environment, a node ad­dress is required. The node address setting is made on the gauge.

The gauge is connected to Profibus via the 9-pin Profibus connector (→  22).

interface at the same time.

The node address (0 … 125
(00 … 7D

) via the "ADDRESS", "MSD", and "LSD" switches.

hex

) is set in hexadecimal form

dec

The node address is polled by the firmware when the gauge is
switched on. If the setting deviates from the stored value, the
new value is taken over into the NVRAM. If a value >7D
(>125

) is entered, the node address setting currently stored in

dec

the device remains valid but it can now be defined via Profibus
("Set slave Address", →  [2]).

Default address setting is 5C

hex

.

hex

36

tina46e1-a (2010-03) BPG402.om

4.12 Switching Functions

The BPG402-S, SL have one, the gauges BPG402-SD and BPG402-SP have two
independent, manually adjustable switching functions. Each switching function has
a floating, normally open relay contact. The relay contacts are accessible at the
sensor cable connector (→  19, 20).

The threshold values of the switching functions can be set within the pressure
range 1×10

-9

mbar … 100 mbar via potentiometers "SETPOINT" (BPG402-S, SL)

or "SETPOINT A" and "SETPOINT B" (BPG402-SD, SP).
The following rule applies:

U

Threshold

= 0.75 × (log p

Setpoint

– c) + 7.75

Where constant c is pressure unit dependent (→ Appendix A).

Measuring Signal
(Pressure p)

e

u

l

a

v

d

e

r

u

s

a

e

M

Hysteresis
10% U

Threshold

U

Threshold

(Setpoint A, B)

Time t

Switching function

Off

On

Off

The hysteresis of the switching functions is 10% of the threshold setting.

tina46e1-a (2010-03) BPG402.om 37

4.12.1 Setting the Switching
Functions

Required tools

Procedure

The threshold values of the switching functions are set locally on the potentiome­ters of the gauge that are accessible via the openings on one side of the gauge
housing.

• Voltmeter

• Ohmmeter or continuity checker

• Screwdriver, max. ø2.5 mm

The procedure for setting thresholds is identical for all switching functions.

 Put the gauge into operation.
 Connect the + lead of a voltmeter to the threshold measurement point of the

respective switching function (Pin 3 or Pin 6).
Connect the – lead of the voltmeter to a ground contact nearby (e.g. locking

screw of the connector, vacuum flange or housing of the gauge).

The threshold voltages are referenced to ground (housing, vacuum

connection), not to Pin 5 (common power GND 24

BPG402-S

BPG402-SL

Setpoint Pin 3

BPG402-SD

( )

V supply).

BPG402-SP

Setpoint
Setpoint B Pin 6

A

Pin 3

( )

max. ø2.5

max. ø2.5

 Using a screwdriver (max. ø2.5 mm), set the voltage of the selected

switching function to the desired value U

There is no local visual indication of the status of the switching functions.

However, a functional check of the switching functions (On/Off) can be
made with one of the following methods:

• Reading the status via fieldbus interface, for BPG402-SD →  [1],
for BPG402-SP →  [2].

• Measurement of the relay contacts at the sensor cable connector
with an ohmmeter / continuity checker (→  19, 20).

Threshold

.

38

tina46e1-a (2010-03) BPG402.om

5 Deinstallation

DANGER: contaminated parts
Contaminated parts can be detrimental to health and environment.
Before beginning to work, find out whether any parts are contaminated.

Adhere to the relevant regulations and take the necessary precautions
when handling contaminated parts.

Caution: vacuum component
Dirt and damages impair the function of the vacuum component.
When handling vacuum components, take appropriate measures to

ensure cleanliness and prevent damages.

DANGER

Caution

Caution

Procedure

Caution: dirt sensitive area
Touching the product or parts thereof with bare hands increases the

desorption rate.
Always wear clean, lint-free gloves and use clean tools when working

in this area.

 Vent the vacuum system.

Before taking the gauge out of operation, make sure that this has

no adverse effect on the vacuum system.
Depending on the programming of the superset controller, faults

may occur or error messages may be triggered.
Follow the appropriate shut-down and starting procedures.

 Take gauge out of operation, switch power supply off.

 Disconnect all cables from the gauge.

tina46e1-a (2010-03) BPG402.om 39

 Remove gauge from the vacuum system and replace the protective lid.

Protective lid

40

tina46e1-a (2010-03) BPG402.om

6 Maintenance, Repair

6.1 Cleaning the Gauge

DANGER

DANGER: contaminated parts
Contaminated parts can be detrimental to health and environment.
Before beginning to work, find out whether any parts are contaminated.

Adhere to the relevant regulations and take the necessary precautions

Small deposits on the electrode system can be removed by baking the anode
(Degas →  27). In the case of severe contamination, the baffle can be exchanged
easily (→  15). The sensor itself cannot be cleaned and needs to be replaced in
case of severe contamination (→  44).

A slightly damp cloth normally suffices for cleaning the outside of the unit. Do not
use any aggressive or scouring cleaning agents.

when handling contaminated parts.

6.2 Adjusting the Gauge

6.2.1 Adjustment at
Atmospheric Pressure

Required tools

Procedure

Make sure that no liquid can penetrate the product. Allow the product to

dry thoroughly before putting it into operation again.

Gauge failures due to contamination, as well as expendable parts

(filament), are not covered by the warranty.

The gauge is factory-calibrated. Through the use in different climatic conditions,
fitting positions, aging or contamination (→  27) and after exchanging the sensor
(→  44) a shifting of the characteristic curve can occur and readjustment can be­come necessary. Only the Pirani part can be adjusted.

At the push of a button the digital value and thus the analog output are adjusted
electronically to +10 V (1000 mbar) at atmospheric pressure.

Adjustment is necessary if

• at atmospheric pressure, the measured value is < atmospheric pressure.

• venting the system, the measured value reaches its maximum before the actual

pressure has reached atmospheric pressure.

This applies to the analog output signal, the pressure value indicated by the
gauges featuring a display and the pressure value output by the digital interfaces.

• Pin approx. ø1.3 × 50 mm (e.g. a bent open paper clip)

 Operate gauge for approx. 10 minutes at atmospheric pressure.

If the gauge was operated before in the Bayard-Alpert range, a

cooling-down time of approx. 30 minutes is to be expected
(gauge temperature = ambient temperature).

tina46e1-a (2010-03) BPG402.om 41

Insert the pin through the opening shown in the following illustration and



push the button inside for 1 s.

BPG402-S

BPG402-SL

BPG402-SD
BPG402-SP

max. ø1.3

6.2.2 Zero Point Adjustment

6.3 What to Do
in Case of Problems

Required tools / material

Troubleshooting (Gauge)

Gauges with display will show the
reading "1000 mbar".

Zero point readjustments are automatically carried out during operation of the
gauge, no manual adjustment is needed.

In the event of a fault or a complete failure of the output signal, the gauge can eas­ily be checked.

• Voltmeter / ohmmeter

• Allen wrench, AF 2.5

• Spare sensor (if the sensor is faulty)

The output signal is available at the sensor cable connector (Pin 2 and Pin 12).

In case of an error, it may be helpful to just turn off the mains supply and

turn it on again after 5 s.

42

tina46e1-a (2010-03) BPG402.om

Troubleshooting (sensor)

Problem Possible cause Correction
Output signal

permanently ≈0V

Sensor cable defective or
not correctly connected

Check the sensor cable

No supply voltage Turn on the power supply
Gauge in an undefined

status

Output signal ≈+0.1 V

EEPROM failure Turn the gauge off and on

(Display: "FAIL EL")

Turn the gauge off and on
again (reset)

again after 5 s
Replace the electronics

unit

Output signal ≈+0.3 V
(Display: "FAIL Ion")

Hot cathode error
(sensor defective)

→ also  28, filament
status

Output signal ≈+0.5 V
(Display: "FAIL Pir")

Pirani error
(sensor defective)

Electronics unit not

mounted correctly on

Replace the sensor
(→  44)

1)

Replace the sensor
(→  44)

Check the connections
(Electronics — sensor)

sensor

Corrupted or no signal
Display: "no Signal"

Internal data connection
not working

Turn the gauge off and on
again after 5 s

Replace the electronics
unit

1)

Pressing the button on the side of the gauge will reset the filament status (only

in the hot cathode range). Subsequently the gauge will test the filaments again
(test time ≈8 sec. / filament). If the error still exists, the gauge will immediately
return into the error state.

If the cause of a fault is suspected to be in the sensor, the following checks can be
made with an ohmmeter (the vacuum system need not be vented for this purpose).

Separate the sensor from the electronics unit (→  14). Using an ohmmeter, make
the following measurements on the contact pins.

All unmarked pins in the diagram are used by the sensor electronics and

cannot be utilized for diagnostic purposes (do not connect an ohmme­ter / continuity checker to these pins).

Ohmmeter measure-

ment between pins

2 + 4
4 + 5
6 + 7
7 + 8
4 + 1

6/7/8 + 1

3 + 1
9 + 1

6/7/8 + 3

9 + 3

1)

→ also "Filament Status",  28).

≈37 Ω >>37 Ω

≈37 Ω >>37 Ω
≈0.15 Ω >>0.15 Ω
≈0.15 Ω >>0.15 Ω

∞ << ∞
∞ <<
∞ <<
∞ <<
∞ <<
∞ <<

Possible cause
Pirani element 1 broken

Pirani element 2 broken
Filament 1 of hot cathode broken 1)
Filament 2 of hot cathode broken 1)
Electrode - short circuit to ground
Electrode - short circuit to ground

∞

Electrode - short circuit to ground

∞

Electrode - short circuit to ground

∞

Short circuit between electrodes

∞

Short circuit between electrodes

∞

tina46e1-a (2010-03) BPG402.om 43

View on sensor pins

7

6

5

4

8

2

3

6

Hot cathode (FIL 1) ca. 0.15 Ohm

7

Hot cathode (FIL 2) ca. 0.15 Ohm

8

1

2

Pirani sensor 1 ca. 37 Ohm

4

Pirani sensor 2 ca. 37 Ohm

5

9

3
1

GND (connected to sensor hou sing)

9

Ion collector

Correction

Troubleshooting on
Fieldbus gauges
(BPG402-SD, -SP)

6.4 Replacing the Sensor

Required tools / material

Procedure

All of the above faults can only be remedied by replacing the sensor (→  44).

Error diagnosis of fieldbus gauges can only be performed as described above for
the basic sensor and sensor electronics. Diagnosis of the fieldbus interface can
only be done via the corresponding bus controller (→  [1], [2]).

For diagnosis of the BPG402-SD (DeviceNet) gauges, the built in LEDs might pro­duce some useful information (→  35).

Replacement is necessary, when

• the sensor is severely contaminated

• the sensor is mechanically deformed

• the sensor is faulty, e.g. one / both filaments of hot cathode broken (→  42)

• the sensor is faulty, e.g. Pirani element broken (→  42)

INFICON recommends the replacement of the sensor as soon as the

first filament failure has been detected.

• Allen wrench, AF 2.5

• Spare sensor (→  45)

 Deinstall the gauge (→  39).
 Deinstall the electronics unit from the faulty sensor and mount it to the new

sensor (→  14).

 Adjust the gauge (→  41).

44

tina46e1-a (2010-03) BPG402.om

7 Options

8 Spare Parts

BPG402-S, -SD, -SP

BPG402-SL

Ordering number
24 VDC power supply / RS232C line (→  23)
Baffle DN 25 ISO-KF / DN 40 CF-R (→  15)

353-511
353-512

When ordering spare parts, always indicate:

• All information on the product nameplate

• Description and part number

Ordering number
Replacement sensor, DN 25 ISO-KF

(including allen wrench)
Replacement sensor, DN 40 CF-R

(including allen wrench)

354-494

354-495

Ordering number
Replacement sensor, DN 40 CF-R, long tube

(including allen wrench)

354-496

9 Storage

Caution: vacuum component
Inappropriate storage leads to an increase of the desorption rate

and/or may result in mechanical damage of the product.
Cover the vacuum ports of the product with protective lids or grease

free aluminum foil. Do not exceed the admissible storage temperature
range (→  11).

Caution

tina46e1-a (2010-03) BPG402.om 45

10 Returning the Product

WARNING

WARNING: forwarding contaminated products
Contaminated products (e.g. radioactive, toxic, caustic or biological

hazard) can be detrimental to health and environment.
Products returned to INFICON should preferably be free of harmful

substances. Adhere to the forwarding regulations of all involved coun­tries and forwarding companies and enclose a duly completed decla-

Products that are not clearly declared as "free of harmful substances" are decon­taminated at the expense of the customer.

Products not accompanied by a duly completed declaration of contamination are
returned to the sender at his own expense.

ration of contamination (→  51).

11 Disposal

Separating the components

Contaminated components

Other components

DANGER

DANGER: contaminated parts
Contaminated parts can be detrimental to health and environment.
Before beginning to work, find out whether any parts are contaminated.

Adhere to the relevant regulations and take the necessary precautions
when handling contaminated parts.

WARNING

N

After disassembling the product, separate its components according to the follow­ing criteria:

Contaminated components (radioactive, toxic, caustic or biological hazard etc.)
must be decontaminated in accordance with the relevant national regulations,
separated according to their materials, and disposed of.

Such components must be separated according to their materials and recycled.

WARNING: substances detrimental to the environment
Products or parts thereof (mechanical and electric components, oper-

ating fluids etc.) can be detrimental to the environment.
Dispose of such substances in accordance with the relevant local

regulations.

46

tina46e1-a (2010-03) BPG402.om

Appendix

A: Relationship Output

Signal – Pressure

Conversion formulae

Conversion curve

p = 10

(U - 7.75) / 0.75 + c

U = 0.75 × (log p - c) + 7.75

where U p c

[V] [mbar] 0
[V] [Pa] 2
[V] [Torr] -0.125

Pressure p [mbar]

1E+04

1E+03

1E+02

1E+01
1E+00

Conversion table

1E–01

1E–02

1E–03

1E–04

sensor error

1E–05
1E–06

1E–07

1E–08

1E–09
1E–10

0.0

Output signal U

[V]

0.1 / 0.3 / 0.5

inadmissible range

1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0

Measuring signal U [V]

[mbar]

Pressure p

[Torr]

Sensor error (→  42)

inadmissible range

[Pa]

0.51 … 0.774 Inadmissible range

0.774 5×10

-10

3.75×10

1.00 1×10-9 7.5×10

-10

5×10-8

-10

1×10-7

1.75 1×10-8 7.5×10-9 1×10-6

2.5 1×10-7 7.5×10-8 1×10-5

3.25 1×10-6 7.5×10-7 1×10-4

4.00 1×10-5 7.5×10-6 1×10-3

4.75 1×10-4 7.5×10-5 1×10-2

5.50 1×10-3 7.5×10-4 1×10-1

6.25 1×10-2 7.5×10-3 1×100

7.00 1×10-1 7.5×10-2 1×101

7.75 1×100 7.5×10-1 1×102

8.50 1×101 7.5×100 1×103

9.25 1×102 7.5×101 1×104

10.00 1×103 7.5×102 1×105

>10.00 Inadmissible range

tina46e1-a (2010-03) BPG402.om 47

B: Gas Type Dependence

Indication range
above 10

Calibration in pressure range

-2

10

-2

mbar

… 1 mbar

Pressure indicated (gauge adjusted for air, Pirani-only mode)

p (mbar)

2

10

8
6

4
2

1

10

8
6

4
2

0

10

8
6

4
2

–1

10

8
6

4
2

–2

10

8
6

4
2

–3

10

10

H2O
vapor

–3

246

Indication range
above 10

10

–2

246

-2

mbar

–1

10

246

0

10

H2He Ne

246

10

1

246

Air
O2
CO
N2

p

eff

CO

2

Ar
Freon 12

Kr
Xe

2

10

(mbar)

The gas type dependence in the pressure range 10-2 … 1 mbar (Pirani pressure
range) can be compensated by means of the following formula:

p

= C × indicated pressure

eff

where Gas type Calibration factor C
Air, O2, CO 1.0
N

0.9

2

CO2 0.5
Water vapor 0.7
Freon 12 1.0
H

0.5

2

He 0.8
Ne 1.4
Ar 1.7
Kr 2.4
Xe 3.0

(The above calibration factors are mean values)

48

tina46e1-a (2010-03) BPG402.om

Calibration in pressure range

-3

<10

mbar

The gas type dependence in the pressure range <10-3 mbar can be compensated
by means of the following formula (gauge adjusted for air):

p

= C × indicated pressure

eff

where Gas type Calibration factor C
Air, O2, CO, N2 1.0
N

1.0

2

He 5.9
Ne 4.1
H

2.4

2

Ar 0.8
Kr 0.5
Xe 0.4

(The above calibration factors are mean values.)

A mixture of gases and vapors is often involved. In this case, accurate

determination is only possible with a partial-pressure measuring instru­ment.

tina46e1-a (2010-03) BPG402.om 49

C: Literature

 [1] www.inficon.com

Communication Protocol
DeviceNet™ BPG402-SD
tira46e1 (English)
INFICON AG, LI–9496 Balzers, Liechtenstein

 [2] www.inficon.com

Communication Protocol
Profibus BPG402-SP
tira47d1 (German)
tira47e1 (English)
INFICON AG, LI–9496 Balzers, Liechtenstein

 [3] www.inficon.com

Product descriptions and downloads
INFICON AG, LI–9496 Balzers, Liechtenstein

 [4] www.odva.org

Open DeviceNet Vendor Association, Inc.
DeviceNet™ Specifications

 [5] www.profibus.com

Profibus user organization

 [6] European Standard for DeviceNet, EN 50325
 [7] European Standard for Profibus, EN 50170
 [8] www.inficon.com

Instruction Sheet
BPG402-S, BPG402-SD, BPG402-SL, BPG402-SP
tima46d1 (German)
tima46e1 (English)
INFICON AG, LI–9496 Balzers, Liechtenstein

 [9] www.inficon.com

Instruction Sheet
BPG402-SD, BPG402-SP
tima47d1 (German)
tima47e1 (English)
INFICON AG, LI–9496 Balzers, Liechtenstein

50

tina46e1-a (2010-03) BPG402.om

Declaration of Contamination

The service, repair, and/or disposal of vacuum equipment and components will only be carried out if a correctly completed declaration has
been submitted. Non-com ple tion will res ult in delay.

This declaration may only be completed (in bloc k letters) and sig ned by authorized and qualified staff.

Description of product

Type
Part number
Serial number

The product is free of any sub­stances which are damaging to
health. yes

Reason for return

Operating fluid(s) used

Used in copper process

no  yes

Process related contaminatio n of produc t :

toxic no  1) yes
caustic no  1) yes 
biological hazard no  yes  2)
explosive no  yes  2)
radioactive no  yes  2)
other harmful substances no  1) yes



1) or not containing any amount
of hazardous residues that
exceed the permissible ex­ posure limits



(Must be drained before shipping.)

Seal product in pla st ic ba g and
mark it with a corresponding label.





2) Products thus contami­ nated will not be ac­ cepted without written
evidence of decontami­ nation.

Harmful substances, gases and/or by-products

Please list all substances, gases, a nd by-products w h ich t h e product may have com e i nt o c ont act with:

Trade/product name

Chemic al nam e
(or symbol)

Precaut i on s as so ci ate d
with substance

Acti on if hum an cont act

Legally binding declaration:

We hereby declare that the information on this form is comple te and accur at e and t hat we wi ll assume any further costs that may
arise. The contaminated product will be di spat ched in accordance with the applicable regulations.

Organization/company
Address Post code, place
Phone Fax
Email
Name

Date and legally binding signature Com pany stamp

This form can be downloaded
from our website.

Copies:
Original for addresee - 1 copy for accompanying documents - 1 copy for file of sender

tina46e1-a (2010-03) BPG402.om 51

LI–9496 Balzers
Liechtenstein
Tel +423 / 388 3111
Fax +423 / 388 3700

Original: German tina46d1-a (2010-03) [e-mail]

t i na46e1- a

www.inficon.com