Operating Instructions
Compact
FullRange™ Gauge
FPM sealed
PKR 251
BG 805 155 BE / C (2008-04) 1
Contents
Product Identification 3
Validity 3
Intended Use 3
Functional Principle 3
1 Safety 4
1.1 Symbols Used 4
1.2 Personnel Qualifications 4
1.3 Safety Information 4
1.4 Liability and Warranty 5
2 Technical Data 6
3 Installation 9
3.1 Installation 9
3.1.1 Removing the Magnet Unit (Only for Gauges With CF Flanges) 10
3.2 Electrical Connection 11
3.2.1 Use With a Pfeiffer Vacuum Measurement Unit 11
3.2.2 Use With Another Evaluation Unit 11
4 Operation 13
4.1 Measurement Principle, Measuring Behavior 13
5 Maintenance 15
5.1 Adjusting the Gauge 15
5.2 Cleaning the Gauge / Replacing Parts 16
5.2.1 Disassembling the Gauge 17
5.2.2 Cleaning the Gauge 18
5.2.3 Reassembling the Gauge 19
5.3 What to Do in Case of Problems 20
6 Removing the Gauge From the Vacuum System 21
7 Returning the Product 22
8 Accessories 22
9 Spare Parts 23
10 Disposal 24
Appendix 25
A: Measuring Signal vs. Pressure 25
B: Gas Type Dependence 27
Declaration of Contamination 29
For cross references within this document, the symbol (→ XY) is used, for
references to other documents, the symbol (→ [Z]).
2
BG 805 155 BE / C (2008-04) PKR 251
Product Identification
In all communications with Pfeiffer Vacuum, please specify the information given
on the product nameplate.
Pfeiffer Vacuum, D - 35614 Asslar
Typ:
No:
F-No:
V ; W
TM
VACUUM
FullRange
Compact
Gauge
Validity
Intended Use
Functional Principle
This document applies to products with part number
PT R26 000
PT R26 001
PT R26 002
(DN 25 ISO-KF flange)
(DN 40 ISO-KF flange)
(DN 40 CF-F flange)
The part number can be taken from the product nameplate.
We reserve the right to make technical changes without prior notice.
The PKR 251 Compact FullRange™ Gauge has been designed for vacuum
measurement in the pressure range of 5×10-9 … 1000 mbar.
The PKR 251 can be used with a Pfeiffer Vacuum measurement unit for Compact
Gauges or with another evaluation unit.
Over the whole measurement range, the measuring signal is output as a logarithm
of the pressure.
The PKR 251 gauge consists of two separate measurement systems (the Pirani
and the cold cathode system according to the inverted magnetron principle). They
are combined in such a way that for the user, they behave as one single measurement system.
BG 805 155 BE / C (2008-04) PKR 251 3
1 Safety
1.1 Symbols Used
1.2 Personnel Qualifications
1.3 Safety Information
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.
Skilled personn e l
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 custodian of the product.
• Adhere to the applicable regulations and take the necessary precautions for the
process media used.
Consider possible reactions between the materials (→ 8) and the process
media.
Consider possible reactions of the process media 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 information in this document.
• Before you begin to work, find out whether any vacuum components are contaminated. Adhere to the relevant regulations and take the necessary precautions when handling contaminated parts.
DANGER
DANGER: magnetic fields
Strong magnetic fields can disturb electronic devices like heart
pacemakers or impair their function.
Maintain a safety distance of ≥10 cm between the magnet and the
heart pacemaker or prevent the influence of strong magnetic fields by
Pass on the safety information to other users.
4
antimagnetic shielding.
BG 805 155 BE / C (2008-04) PKR 251
1.4 Liabilit y and Warranty
Pfeiffer Vacuum assumes no liability and the warranty becomes null and void if the
custodian or third parties
• disregard the information in this document
• use the product in a non-conforming manner
• make any kind of changes (modifications, alterations etc.) to the product
• use the product with accessories not listed in the corresponding product
documentation.
The custodian 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.
BG 805 155 BE / C (2008-04) PKR 251 5
2 Technical Data
Admissible temperatures
Storage
Operation
Bakeout
-40 °C … +65 °C
+ 5 °C … +55 °C
+150 °C (without electronics unit and
magnetic shielding)
Relative humidity
max. 80% at temperatures ≤+31 °C
decreasing to 50% at +40 °C
Use indoors only
altitude up to 2000 m (6600 ft)
Measurement range (air, N2) 5×10-9 … 1000 mbar
Accuracy
Reproducibility
Gas type dependence
≈±30%
in the range 1×10
≈±5%
in the range 1×10
→ Appendix B
-8
… 100 mbar
-8
… 100 mbar
Adjustment
(→ 15)
Pirani measurement circuit
<HV> trimmer potentiometer
at <1×10
-4
mbar
(while depressing the pin)
<ATM> trimmer potentiometer at atmospheric pressure
Cold cathode measurement circuit no adjustment (the gauge is adjusted at
the factory and requires no maintenance)
Type of protection IP 40
Maximum pressure (absolute) 10 bar
only for inert gases <55 °C
Supply
DANGER
The gauge may only be connected to supply or measurement units
that conform to the requirements of a grounded protective extra-low
voltage (SELV-E according to EN 61010). The connection to the
gauge has to be fused.
Voltage at the gauge 15.0 … 30.0 VDC (max. ripple 1 V
Power consumption
1)
Fuse
The minimum voltage of the power supply must be increased proportionally to the
length of the measuring cable.
Voltage at the supply unit with
maximum cable length
Electrical connection Hirschmann compact connector
Cable 5 poles plus screening
Maximum cable length 75 m (0.25 mm² conductor)
1)
Pfeiffer Vacuum measurement and control units for Compact Gauges fulfill
these requirements.
6
1)
≤2 W
≤1 AT
16.0 … 30.0 VDC (max. ripple 1 V
type GO 6, 6 pins, male
100 m (0.34 mm² conductor)
300 m (1.0 mm² conductor)
)
pp
)
pp
BG 805 155 BE / C (2008-04) PKR 251
Operating voltage
(in the measuring chamber)
Operating current
(in the measuring chamber)
≤3.3 kV
≤500 µA
Output signal (measuring signal)
Voltage range
≈0 V … ≈+10.5 V
Relationship voltage-pressure logarithmic, increase 0.6 V / decade
(→ Appendix A)
Error signals <0.5 V (no supply)
>9.5 V (Pirani measurement element
defective; filament rupture)
Output impedance
Minimum load
2×10 Ω
10 kΩ, short-circuit proof
Response time pressure dependent
-6
p > 10
p = 10
mbar
-8
mbar
≈10 ms
≈1 s
Gauge identification
Pirani-only mode
→ Figure 1
11.1 kΩ resistor referenced to supply
common
Combined Pirani / cold cathode
mode
The following conditions must be
9.1 kΩ resistor referenced to supply
common
fulfilled:
Polarity The polarity of pin 1 referenced to
supply common is always positive.
Measurement
with constant current
with constant voltage
measurement current within range
0.2 … 0.3 mA
measurement voltage within range
2 … 3 V
Grounding concept
Vacuum flange-measurement
common
→ Figure 1
connected via 10 kΩ
(max. voltage differential
with respect to safety ±50 V
with respect to accuracy ±10 V)
Supply common-signal common conducted separately; differential
measurement recommended for cable
lengths ≥6 m
BG 805 155 BE / C (2008-04) PKR 251 7
PT R26 000 (DN 25 ISO-KF)
PT R26 001 (DN 40 ISO-KF)
PT R26 002 (DN 40 CF-F)
Materials exposed to the vacuum
Flange
Measuring chamber
Feedthrough isolation
Internal seals
Anode
Ignition aid
Pirani measuring tube
Pirani filament
Internal volume
stainless steel (1.4104)
stainless steel (1.4104)
ceramic (Al2O3), glass
FPM75
Mo
stainless steel (1.4310/AISI 301)
Ni, Au
W
≈ 20 cm³
Dimensions [mm]
DN 40 CF-F DN 40 ISO-KF
18.5
24
101.5
28 55
ø 63,5
107
VACUUM
Compact
Full Range
Gauge
20
TM
Weight 700 g
Materials exposed to the vacuum
Flange
Measuring chamber
Feedthrough isolation
Internal seals
Anode
Ignition aid
Pirani measuring tube
Pirani filament
Internal volume
stainless steel (1.4306/AISI 304L)
stainless steel (1.4104)
ceramic (Al
2O3
), glass
FPM75
Mo
stainless steel (1.4310/AISI 301)
Ni, Au
W
≈ 20 cm³
Dimensions [mm]
18.5
101.5
28 55
20
Weight 700 g (DN 40 ISO-KF flange)
950 g (DN 40 CF-F flange)
8
DN 40 CF-F DN 40 ISO-KF
VACUUM
Compact
TM
Full Range
ø 63,5
24
107
Gauge
BG 805 155 BE / C (2008-04) PKR 251
3 Installation
3.1 Installation
Procedure
Caution
Caution: vacuum component
Dirt and damages impair the function of the vacuum component.
When handling vacuum components, take appropriate measures to
The gauge can be mounted in any orientation. However, it should be mounted so
that any particles present cannot penetrate into the measuring chamber (→ 14).
See "Technical data" (→ 8) for space requirements.
ensure cleanliness and prevent damages.
Remove the protective cap.
The protective cap will be
needed for maintenance work.
Make the flange connection.
When making a CF flange connection, it
can be advantageous to temporarily
remove the magnet unit
(→ section 3.1.1).
If it should be possible to adjust the gauge while it is connected to the
vacuum system, make sure the two <HV> and <ATM> trimmer potentiometers are accessible for a screw driver.
DANGER
DANGER: overpressure in the vacuum system >2.5 bar
KF flange connections with elastomer sealing rings (e.g.
O-rings) cannot withstand such pressures. Process media can
thus leak and possibly damage your health.
Use sealing rings provided with an outer centering ring.
DANGER
DANGER: overpressure in the vacuum system >1 bar
If clamps are opened unintentionally injury can be caused by
catapulted parts.
Use the type of clamps which can only be opened and closed
by means of a tool (e.g. hose clip clamping ring).
DANGER
The gauge must be electrically connected to the grounded
vacuum chamber. The connection must conform to the requirements of a protective connection according to EN 61010:
• CF flanges fulfill this requirement
• For gauges with KF flanges, use a conductive metallic
clamping ring.
BG 805 155 BE / C (2008-04) PKR 251 9
3.1.1 Removing the Magnet
Unit (Only for Gauges
With CF Flanges)
Tools required
Procedure
WARNING: electric arcing
Helium may cause electric arcing with detrimental effects on the
electronics of the product.
Before performing any tightness tests put the product out of
• Allen wrench 1.5 mm
• Open-end wrench 7.0 mm
operation and remove the electronics unit.
4
3
WARNING
2
7
1
Unfasten the socket head set screw (1) on the side of the electronics unit
(2).
Remove the electronics unit without twisting it.
Unfasten the hexagon head screw (3) on the magnet unit (4) and remove
the magnet unit.
Caution
The magnetic force and the tendency to tilt make it more
difficult to separate the magnet unit and the measuring chamber
(7).
Make the flange connection between the gauge and the vacuum system.
Remount the magnet unit and lock it with the hexagon head screw (3).
Carefully mount the electronics unit (2). (Make sure the pin of the Pirani ele-
ment is properly plugged into the corresponding hole of the electronics unit.)
Push the electronics unit up to the mechanical stop and lock it with the
hexagon socket set screw (1).
10
BG 805 155 BE / C (2008-04) PKR 251
3.2 Electrical Connection
3.2.1 Use With a
Pfeiffer Vacuum
Measurement Unit
3.2.2 Use With Another
Evaluation Unit
Procedure
If the gauge is used with a
Pfeiffer Vacuum measurement
unit for Compact Gauges, a
corresponding connection cable
is required (→ 22).
• Secure the connector on the
gauge with the screw.
TM
VACUUM
FullRange
Compact
Gauge
The gauge can also be operated with other evaluation units. In this case, an
individual connection cable must be made.
2
For cable lengths up to 6 m (with a conductor cross-section of 0.34 mm
), the
measuring signal can be read directly between the positive signal output (pin 2)
and the supply common (pin 5) without the degree of accuracy being lowered. For
longer measurement cable lengths, we recommend a differential measurement
between the signal output and the signal common (pin 3) (as a result of the voltage
drop along the supply cable ground lead, the common mode signal is approx. 1.0 V
at the maximum admissible cable length).
Prepare the connector (ordering
number → 22).
Solder the connection cable according to the diagram.
10
10
Ident
10k
2
3
1
4
5
6
Figure 1
Connector, soldering side
: Electrical connection
Pin 1 identification
Pin 2 signal output
(measuring signal)
Pin 3 signal common
Pin 4 supply
Pin 5 supply common
Pin 6 screen
2
3
4
5
1
6
+
V
–
+
–
BG 805 155 BE / C (2008-04) PKR 251 11
The supply common (pin 5) and the screen (pin 6) must be
connected to the supply unit with protective ground.
Incorrect connection, incorrect polarity, or inadmissible supply
voltages can damage the gauge.
Reassemble the connector.
Plug in the connector.
Secure the connector on the
gauge with the screw.
WARNING
TM
VACUUM
FullRange
Compact
Gauge
12
BG 805 155 BE / C (2008-04) PKR 251
4 Operation
4.1 Measurement Principle,
Measuring Behavior
Gas type dependence
Ignition delay
As soon as the required voltage is applied, the measuring signal is available
between pins 2 and 3. (→ Appendix A for the relationship between the measuring
signal and the pressure).
Allow for a stabilizing time of approx. 10 min. Once the gauge has been switched
on, permanently leave it on irrespective of the pressure.
The PKR 251 consists of tow separate measurement systems (Pirani and cold
cathode system according to the inverted magnetron principle). They are combined
in such a way that for the user, they behave as one single measurement system.
The optimum measurement configuration for the particular pressure range, in
which measurement is performed, is used:
10-4 mbar
1000 mbar
Cold cathode Pirani
-2
10
5 × 10-9 mbar
• The Pirani measurement circuit is always on.
• The cold cathode measurement circuit is controlled by the Pirani circuit and is
activated only at pressures <1×10
-2
The identification output (pin 1) indicates the current status of the gauge:
Pressure Green lamp on
the gauge
p > 1×10-2 mbar
p < 1×10-2 mbar
Combined operation
As long as the cold cathode measurement circuit has not ignited, the measurement
value of the Pirani is output as measuring signal (if p < 5×10
underrange" is displayed).
The measuring signal depends on the type of gas being measured. The curves are
accurate for N
, O2, dry air and CO. They can be mathematically converted for
2
other gases (→ Appendix B).
If you are using a Pfeiffer Vacuum measurement unit for Compact Gauges, you
can enter a calibration factor to correct the measurement value displayed (→ of
that measurement unit).
When cold cathode measurement systems are activated, an ignition delay occurs.
The delay time increases at low pressures and is typically:
-5
mbar ≈ 1 second
10
-7
mbar ≈ 20 seconds
10
-9
mbar ≈ 2 minutes
5×10
mbar
mbar.
Operating mode Identification
Pirani-only mode
Pirani-only mode (cold
11.1 kΩ (Pirani)
11.1 kΩ (Pirani)
cathode measurement
circuit not ignited)
9.1 kΩ (combined)
-4
mbar, "Pirani
BG 805 155 BE / C (2008-04) PKR 251 13
Contamination
As long as the cold cathode measurement circuit has not yet ignited, the measurement value of the Pirani is output as measuring signal ("Pirani underrange" is
displayed for pressures <5×10
-4
mbar). The identification output (pin 1) indicates
the Pirani-only mode.
Caution
If the gauge is activated at a pressure p < 3×10-9, the gauge cannot
recognize whether the cold cathode system has ignited. It indicates
"Pirani-Underrange".
Caution
Once flanged on, permanently leave the PKR 251 gauge in the
operating mode irrespective of the pressure range. Like this, the
ignition delay of the cold cathode measurement circuit is always
Gauge failures due to contamination, as well as expendable parts (filament), are
not covered by the warranty.
Gauge contamination is influenced by the process media used as well as any
present or new contaminants and their respective partial pressures. Continuous
operation in the range of 10
as well as reduced up-time and maintenance cycles. With constantly low pressures
(p < 1×10
cleaning (cleaning the gauge → 18).
Contamination of the gauge generally causes a deviation of the measured values:
• In the high pressure range (1×10-3 mbar ... 0.1 mbar), the pressure indication is
too high (contamination of the Pirani element). Readjustment of the Pirani
measurement system → 15.
• In the low pressure range (p < 1×10
too low (contamination of the cold cathode system). In case of severe contamination, instabilities can occur (layers of the measuring chamber peel off).
Contamination due to insulation layers can even lead to a complete failure of
the discharge ("Underrange" is displayed).
Contamination can to a certain extent be reduced by:
• geometric protection measures (e.g. screenings, elbows) for particles that
spread rectilinearly
• mounting the flange of the gauge at a place where the partial pressure of the
pollutants is particularly low.
Special precautions are required for vapors deposited under plasma (of the cold
cathode measurement system). It may even be necessary to temporarily switch of
the gauge while vapors occur.
negligible (<1 s), and thermal stabilizing effects are minimized.
-4
mbar ... 10-2 mbar can cause severe contamination
-6
mbar), the gauge can be operated for more than one year without
-3
mbar), the pressure indication is usually
14
BG 805 155 BE / C (2008-04) PKR 251
5 Maintenance
5.1 Adjusting the Gauge
Tools required
Procedure
Gauge failures due to contamination, as well as expendable parts (filament), are
not covered by the warranty.
DANGER
DANGER: contaminated parts
Contaminated parts can be detrimental to health and enviroment.
Before you begin to work, find out whether any parts are contaminated. Adhere to the relevant regulations and take the necessary
The gauge is factory-calibrated. Readjusting the gauge can become necessary due
to use under different climatic conditions, aging, or contamination (→ 14).
The cold cathode measurement circuit, which is dominant for low pressures
(<1×10
the Pirani measurement circuit can be adjusted. Any adjustment has a negligible
effect on the pressure range between approx. 10-2 mbar and 102 mbar.
• Screw driver No. 0
• Cylindrical pin ø ≈ 3 mm
precautions when handling contaminated parts.
-3
mbar), is factory-calibrated and cannot be adjusted. By way of contrast,
Put the gauge into operation (if possible, in the position, in which it will be
used later on).
-4
Evacuate the vacuum system to p << 10
mbar, and then wait 10 minutes.
Turn the nameplate counter-clockwise until the mechanical stop is reached.
TM
VACUUM
Compact
FullRange
Gauge
... to 5×10
While depressing the pin with the cylindrical pin,
adjust the <HV> potentiometer
-4
mbar
or
... to 4.2 V.
Then turn the
potentiometer counterclockwise by 1/3.
BG 805 155 BE / C (2008-04) PKR 251 15
Vent with air or nitrogen to atmospheric pressure and then wait 10 minutes.
Turn the nameplate clockwise until the mechanical stop is reached.
TM
VACUUM
FullRange
Compact
... to 1×10
Adjust the <ATM> potentiometer ...
Gauge
3
mbar
or
... to 8.6 V
5.2 Cleaning the Gauge /
Replacing Parts
Tools / material required
Turn the nameplate back to its original position (it will catch).
DANGER
DANGER: cleaning agents
Cleaning agents can be detrimental to health and environment.
Adhere to the relevant regulations and take the necessary precautions
when handling and disposing of cleaning agents. Consider possible
reactions with the product materials (→ 8).
Caution
We recommend to replace the Pirani element when cleaning the
gauge.
• Allen wrench 1.5 mm
• Allen wrench 3.0 mm
• Open-end wrench 7.0 mm
• Pliers for circlip
• Polishing cloth (400 grain) or Scotch-Brite
• Tweezers
• Cleaning alcohol
• Mounting tool for ignition aid
• Ignition aid
• Pirani element (13) incl. FPM seal (13a)
• FPM seal (11) for anode feedthrough
16
BG 805 155 BE / C (2008-04) PKR 251
5.2.1 Disassembling the Gauge
2
4
3
1
7
6
5
13
13a
8a
8
Procedure
Figure 2
12
11
10a
10
9
Remove the gauge from the vacuum system (→ Fehler! Textmarke
nicht definiert.).
Unfasten the socket head set screw (1) on the side of the electronics unit
(2) (→ Figure Fehler! Verweisquelle konnte nicht gefunden werden.).
Remove the electronics unit without twisting it.
Caution
The cover of the electronics unit cannot be removed.
Unfasten the hexagon head screw (3) on the magnet unit (4) and remove
the magnet unit.
Caution
The magnetic force and the tendency to tilt make it more difficult to separate the magnet unit and the measuring chamber
(7).
Remove the circlip (5) and the polarity insert (6) from the measuring
chamber.
Remove the three hexagon socket screws (8) incl. lock washers (8a) on the
back of the measuring chamber.
BG 805 155 BE / C (2008-04) PKR 251 17
5.2.2 Cleaning the Gauge
Procedure
Carefully remove the following parts in this order (without exerting stress on
the Pirani element (13)): pressure piece (9), complete anode (10), FPM seal
(11) incl. support ring (12), Pirani element (13) incl. FPM seal (13a).
The parts can now be cleaned or replaced individually.
Cleaning the measuring chamber and the polarity insert:
Using a polishing cloth rub the inside walls of the measuring chamber and
the polarity insert to a bright finish.
Caution
The sealing surfaces must only be worked concentrically.
Rinse the measuring chamber and the polarity insert with cleaning alcohol.
Allow both to dry.
Cleaning or replacing the anode:
Remove the old ignition aid (10a), for example with tweezers (→ Figure 2).
Using a polishing cloth rub the anode pin to a bright finish.
Caution
Do not bend the anode. Do not carry out mechanical work on
the ceramic part.
Rinse the anode with cleaning alcohol.
Allow the anode to dry.
Insert a new ignition aid (10a) into the mounting tool.
Carefully press the anode (clean or new)
centered and parallel to the tool axis into
the ignition aid and insert it to a depth of
approx. 15 mm. The final positioning is
established after the anode is installed.
Cleaning the Pirani element:
Remove the FPM seal (13a) from the Pirani element (13).
Fill the Pirani measuring tube with cleaning alcohol and let it work.
Pour the alcohol out of the tube.
18
Anode
Ignition aid
Mounting tool
BG 805 155 BE / C (2008-04) PKR 251
5.2.3 Reassembling the Gauge
Procedure
Dry the tube (e.g. with a blow dryer <150°C).
Slide a new FPM seal over the Pirani element and insert it into the corre-
sponding groove.
Remount the Pirani element (→ section 5.2.3).
Replacing the Pirani measurement element:
(If it is severely contaminated or defective)
Slide a new FPM seal (13a) over the Pirani element (13) and insert it into
the corresponding groove.
Mount the Pirani element (→ section 5.2.3).
Insert the FPM seal (11) with the support ring (12) centered into the
measuring chamber (7). The sealing surface, seal, and ceramic part must
be clean (→ Figure 2).
Carefully insert the anode (10) incl. ignition aid (10a) into the measuring
chamber.
Insert the Pirani element (13) with the FPM seal (13a) slid over it into the
corresponding bore hole.
Carefully place the pressure piece (9) on the measuring chamber and
tighten them with the three hexagon socket screws (8) incl. lock washers
(8a) uniformly until the stop position is reached.
Position the ignition aid (10a) by pushing the mounting tool over the anode
pin until the mechanical stop is reached.
Blow the particles in the measuring chamber with dry nitrogen (be careful to
hold the measuring chamber with the flange pointing downwards).
Slide the polarity insert (6) into the measuring chamber until the mechanical
stop is reached.
Place the circlip (5) snugly fitting on the polarity insert.
Caution
Visually check that the anode pin is centered over the middle
hole of the polarity insert (max. eccentricity = 0.5 mm).
BG 805 155 BE / C (2008-04) PKR 251 19
5.3 What to Do in Case of
Problems
If possible perform a leak test (leak rate <10
-9
mbar l/s).
WARNING
WARNING: electric arcing
Helium may cause electric arcing with detrimental effects on the
electronics of the product.
Before performing any tightness tests put the product out of
operation and remove the electronics unit.
Mount the magnet unit (4) and lock it with the screw (3).
Carefully mount the electronics unit (2). (Make sure the pin of the Pirani
element is properly plugged into the corresponding hole of the electronics
unit.)
Push the electronics unit up to the mechanical stop and lock it with the
hexagon socket set screw (1).
Adjust the gauge (→ 15).
Problem Possible cause Remedy
Measuring signal
continually < 0.5 V
"Error low".
Measuring signal
continually > 9.5 V
"Error high".
Electronics unit not cor-
The green lamp is ON and
the identification indicates
Pirani-only mode
(measuring signal
continually > 4.0 V)
"Pirani underrange".
The PKR has only been
Measuring signal
continually > 5 V or display
> 10-3 mbar although
vacuum pressure is OK.
Measurement of heavy
Severe outgassing in the
Measuring signal unstable. Gauge contaminated. Clean the gauge
No supply voltage. Turn on the power
supply.
Pirani measurement
element defective
Replace the Pirani
element (→ 18).
(filament rupture).
Mount the electronics
rectly mounted.
The cold cathode discharge has not ignited.
unit correctly (→ 19).
Wait until the gas
discharge ignites (in
case of contamination
with insulation layers, the
cold cathode may
completely fail to ignite).
(Cleaning → 18).
Slightly increase the
activated with
p < 3×10
-9
mbar
Pirani measurement circuit not adjusted, e.g.
due to severe contamination.
pressure.
Readjust the Pirani
measurement circuit
(→ 15). If adjustment
is impossible, replace the
Pirani element.
Convert with the
gases.
corresponding formula
(→ 27).
Clean the measuring
measuring chamber.
chamber.
(→ 18).
20
BG 805 155 BE / C (2008-04) PKR 251
6 Removing the Gauge From the Vacuum System
DANGER
DANGER: contaminated parts
Contaminated parts can be detrimental to health and enviroment.
Before you begin to work, find out whether any parts are contaminated. Adhere to the relevant regulations and take the necessary
precautions when handling contaminated parts.
Procedure
Caution
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.
Deactivate the gauge.
Unplug the connector.
Remove the gauge from the
vacuum system.
TM
VACUUM
Compact
FullRange
Gauge
Place the protective cap.
BG 805 155 BE / C (2008-04) PKR 251 21
7 Returning the Product
WARNING
WARNING: forwarding contaminated products
Products returned to Pfeiffer Vacuum for service or repair should, if
possible, be free of harmful substances (e.g. radioactive, toxic, caustic
or microbiological). Otherwise, the type of contamination must be
declared.
Adhere to the forwarding regulations of all involved countries and
forwarding companies and enclose a completed contamination
Products that are not clearly declared as "free of harmful substances" are decontaminated at the expense of the customer.
declaration.
8 Accessories
Ordering number
Connection cable for Pfeiffer Vacuum
measurement unit for Compact Gauges
3 m
6 m
10 m
Connection socket Hirschmann
GO 6 WF 6 contacts, angled, female
Magnetic shielding
PT 448 250-T
PT 448 251-T
PT 448 252-T
B 4707 283 MA
PT 443 155-X
22
BG 805 155 BE / C (2008-04) PKR 251
9 Spare Parts
4
3
7
13
13a
When ordering spare parts, always indicate:
• the type of product
• the manufacturing number given on the product nameplate
• the position, description, and ordering number according to the spare parts list
The following parts are available as spare parts sets:
Pos. Description Ordering number
2
12
13a
11
10a
1× support ring
1× O-ring FPM 3.69 × 1.78
1× O-ring FPM 10.82 × 1.78
3× ignition aid
Maintenance set, consisting of:
BN 846 239-T
1
8
8a
Repair set, consisting of:
13
12
13a
11
10a
10
1× Pirani measurement element, cpl.
1× support ring
1× O-ring FPM 3.69 × 1.78
1× O-ring FPM 10.82 × 1.78
3× ignition aid
1× anode, complete
Set of ignition aids, consisting of:
10a
10
10a
11
12
9
Mounting tool for ignition aid BG 510 600
2 Electronics unit PKR 251 PT 120 140-T
10× ignition aid
BN 846 238-T
BN 845 995-T
Measuring system, complete
DN 25 ISO-KF flange
DN 40 ISO-KF flange
DN 40 CF-F flange
BN 846 469-T
BN 846 470-T
BN 846 471-T
Exchange gauge
(return defective gauge to Pfeiffer Vacuum)
DN 25 ISO-KF flange
DN 40 ISO-KF flange
DN 40 CF-F flange
PT R26 000-A
PT R26 001-A
PT R26 002-A
BG 805 155 BE / C (2008-04) PKR 251 23
10 Disposal
WARNING
N
WARNING: substances detrimental to the environment
Products, operating materials etc. may have to be specially disposed
of.
For environmentally compatible disposal, please contact your nearest
Pfeiffer Vacuum Service Center.
24
BG 805 155 BE / C (2008-04) PKR 251
Appendix
A: Measuring Signal vs.
Pressure
Conversion formulae
Conversion curves
1.667×U-d
p = 10
⇔
p U c d
[mbar] [V] 6.8 11.33
[µbar] [V] 5.0 8.333
[Torr] [V] 6.875 11.46
[mTorr] [V] 5.075 8.458
[micron] [V] 5.075 8.458
[Pa] [V] 5.6 9.333
[kPa] [V] 7.4 12.33
where U measuring signal
p pressure
c, d constant (pressure
unit dependent)
Pressure p
1E+04
1E+02
U = c + 0.6×log10 p
valid in the range 5×10
3.8×10
5×10
-9
mbar < p
-9
Torr < p
-7
Pa < p
< 1000 mbar
< 750 Torr
< 1×105 pa
Pa
mbar
Torr
1E+00
1E–02
underrange
sensor error
1E–04
1E–06
1E–08
0.0 0.5 1.5 2.5 3.5 4.5 5.5 6.5 7.5 8.5 9.5 10 .5
U[V
overrange
Measuring signal U [V]
sensor error
BG 805 155 BE / C (2008-04) PKR 251 25
Conversion table
Measuring
signal U [V]
[mbar]
Pressure p
[Torr]
< 0.5 Sensor error
0.5 ... 1.82 Underrange
1.82
2.0
2.6
3.2
3.8
4.4
5.0
5.6
6.2
6.8
7.4
8.0
8.6
-9
5.0×10
1.0×10-8
-7
1.0×10
1.0×10-6
-5
1.0×10
1.0×10-4
-3
1.0×10
-2
1.0×10
0.1
1.0
10
100
1000
3.8×10
7.5×10-9
7.5×10
7.5×10-7
7.5×10
7.5×10-5
7.5×10
7.5×10-3
7.5×10
0.75
7.5
75
750
-9
-8
-6
-4
-4
8.6 ... 9.5 Overrange
9.5 ... 10.5 Sensor error (Pirani defective)
[Pa]
5.0×10
1.0×10-6
1.0×10
1.0×10-4
1.0×10
1.0×10-2
0.1
1.0
10
100
1000
1.0×10
1.0×10
-7
-5
-3
4
5
26
BG 805 155 BE / C (2008-04) PKR 251
B: Gas Type Dependence
Indication range above
-2
mbar
10
(Pirani only mode)
Pressure indicated (gauge calibrated for air)
Indication range
-6
... 0.1 mbar
10
Pressure indicated (gauge calibrated for air)
BG 805 155 BE / C (2008-04) PKR 251 27
Indication range below
-5
mbar
4×10
In the range below 10-5 mbar, the pressure indication is linear. For gases other
than air, the pressure can be determined by means of a simple conversion formula:
p
= K × pressure indicated
eff
where gas type K
air (N2, O2, CO) 1.0
Xe 0.4
Kr 0.5
Ar 0.8
H
2.4
2
Ne 4.1
He 5.9
These conversion factors are average values.
Caution
A mixture of gases and vapors is often involved. In this case, accurate
determination is only possible with a partial pressure measurement
instrument, e.g. a quadrupole mass spectrometer.
28
BG 805 155 BE / C (2008-04) PKR 251
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-completion will result in delay.
This declaration may only be completed (in block letters) and signed 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 contamination of product:
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 plastic bag and
mark it with a corresponding label.
2) Products thus contami nated will not be ac cepted without written
evidence of decontami nation.
Harmful subs tances, gases and/or by-products
Please list all substances, gases, and by-products which the product may have come into contact with:
Trade/product name
Chemical name
(or symbol)
Precautions associated
with substance
Action if human contact
Legally binding decl a rat ion:
We hereby declare that the information on this form is complete and accurate and that we will assume any further costs that may
arise. The contaminated product will be dispatched in accordance with the applicable regulations.
Organization/company
Address Post code, place
Phone Fax
Email
Name
Date and legally binding signature Company stamp
This form can be downloaded
from our we bsite.
Copies:
Original for addresee - 1 copy for accompanying documents - 1 copy for file of sender
BG 805 155 BE / C (2008-04) PKR 251 29
Notes
30
BG 805 155 BE / C (2008-04) PKR 251
Notes
BG 805 155 BE / C (2008-04) PKR 251 31
Berliner Strasse 43
D–35614 Asslar
Deutschland
Tel +49 (0) 6441 802-0
Fax +49 (0) 6441 802-202
Original: German BG 805 155 BD / C (2008-04) info@pfeiffer-vacuum.de
bg805155be/ c
www.pfeiffer-vacuum.net
Loading...