WIKA CPB 3000 User manual

Operating Instructions
Betriebsanleitung
CPB 3000
Pressure Balance GB
Pressure Balance CPB 3000
Kolbenmanometer D

Pressure Balance GB
CPB 3000
WIKA Operating Instructions Pressure Balance Version 1.1 2
Information
This symbol provides you with information, notes and tips.
Warning!
This symbol warns you against actions that can cause injury to people or
damage to the instrument.
Operating Instructions Pressure Balance Page 4 - 27GB
Betriebsanleitung Kolbenmanometer Seite 28 - 53D

Pressure Balance GB
CPB 3000
WIKA Operating Instructions Pressure Balance Version 1.1 3
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1. General ....................................................................................................................................... 4
1.1 General Instructions ................................................................................................................... 4
1.2 Safety Instructions ...................................................................................................................... 5
2. Product Description ...................................................................................................................... 6
2.1 General Product Information ..................................................................................................... 6
2.2 Basic principle of the Pressure Balance .................................................................................. 7
2.3 Factors at work ............................................................................................................................ 7
2.3.1 Local fluctuations in the gravity-value .................................................................................. 7
2.3.2 Temperature (Piston/Cylinder) ............................................................................................... 8
2.3.3 Ambient conditions .................................................................................................................. 8
2.3.4 How the cross-sectional surface responds to pressure ...................................................... 9
2.4 Arrangement of control elements ........................................................................................... 10
3. Commissioning and Operation .................................................................................................. 11
3.1 Preparation ................................................................................................................................ 11
3.1.1 Setting up the Device ............................................................................................................. 11
3.1.2 Filling in of operating liquid (first commissioning) ............................................................ 11
3.1.3 Installing the piston/cylinder system ................................................................................... 12
3.1.4 Connecting the test specimen .............................................................................................. 13
3.1.5 Venting the System ................................................................................................................ 13
3.2 Operation .................................................................................................................................. 15
3.2.1 Weight Pieces ......................................................................................................................... 15
3.2.2 Approaching the pressure value .......................................................................................... 16
3.2.3 Pressure stable ...................................................................................................................... 17
3.2.4 Next pressure level ................................................................................................................ 18
3.2.5 Releasing pressure ................................................................................................................ 18
3.3 Disassembly ..............................................................................................................................18
4. Troubleshooting measures ........................................................................................................ 20
5. Maintenance and Care ................................................................................................................ 21
5.1 Cleaning .................................................................................................................................. 21
5.1.1 Piston/Cylinder system ......................................................................................................... 21
5.1.1.1 Layout of the piston/cylinder system ............................................................................... 21
5.1.1.2 Disassembly of the piston/cylinder system ..................................................................... 21
5.1.1.3 Cleaning of the piston/cylinder system ............................................................................ 22
5.1.1.4 Assembly of the piston/cylinder system .......................................................................... 22
5.1.2 Weight Set ...............................................................................................................................22
5.2 Wear Parts ................................................................................................................................. 22
5.3 Changing the Hydraulic Oil ...................................................................................................... 23
5.4 Recalibration ............................................................................................................................. 23
6. Specifications .............................................................................................................................. 24
7. Tables of masses ........................................................................................................................ 26
7.1 Measuring ranges BAR ............................................................................................................. 26
7.2 Measuring ranges PSI ............................................................................................................... 26
8. Accessories ................................................................................................................................. 27

Pressure Balance GB
CPB 3000
WIKA Operating Instructions Pressure Balance Version 1.1 4
1. General .
1.1 General Instructions .
In the following chapters detailed information on the CPB 3000 pressure balance and its proper use
can be found.
Should you require further information, or should there be problems which are not dealt within detail in
the operating instructions, please contact the address below:
WIKA Alexander Wiegand SE & Co. KG
Alexander Wiegand Strasse
D-63911 Klingenberg
Tel: [phone]
Fax: [phone]
E-Mail: [email protected]
If nothing to the contrary is agreed, the pressure balance is calibrated in compliance with the currently
valid body of international regulations and can be referred directly to a national standard.
The warranty period for the pressure balance is 24 months according to the general terms of supply of
ZVEI.
The guarantee is void if the appliance is put to improper use or if the operating instructions are not
observed or if an attempt is made to open the appliance or to release attachment parts or the tubing.
We also point out that the content of these operating instructions neither forms part of an earlier or
existing agreement, assurance or legal relationship nor is meant to change these. All obligations of
WIKA Alexander Wiegand SE & Co. KG result from the respective sales contract and the general
business terms of WIKA Alexander Wiegand SE & Co. KG.
WIKA is a registered trade mark of WIKA Alexander Wiegand SE & Co. KG.
Names of companies or products mentioned in this handbook are registered trade
marks of the manufacturer.
The devices described in this manual represent the latest state of the art in terms of their design,
dimension and materials. We reserve the right to make changes to or replace materials without any
obligation to give immediate notification.
Duplication of this manual in whole or in part is prohibited.
© 2010 Copyright WIKA Alexander Wiegand SE & Co. KG. All rights reserved.

Pressure Balance GB
CPB 3000
WIKA Operating Instructions Pressure Balance Version 1.1 5
1.2 Safety Instructions .
Read these operating instructions carefully prior to operating
the pressure balance CPB 3000. Its trouble-free operation and reliability cannot
be guaranteed unless the safety advise given in this manual is followed when
using the device.
1. The system must only be operated by trained and authorised personnel who know the manual and
can work according to them.
2. Trouble-free operation and reliability of the device can only be guaranteed so long as the
conditions stated under "Setting up the device" are taken into consideration.
3. The CPB 3000 always has to be handled with the care required for an precision instrument (protect
from humidity, impacts and extreme temperatures). The device, the piston-cylinder-system and the
mass-set must be handled with care (don't throw, hit, etc.) and protect them from contamination. By
no means apply any force to the operating elements of the CPB 3000.
4. If the device is moved from a cold to a warm environment, you should therefore ensure the device
temperature has adjusted to the ambient temperature before trying to put it into operation.
5. If the equipment is damaged and might no longer operate safely, then it should be taken out of use
and securely marked in such a way so that isn't used again.
Operator safety may be at risk if:
There is visible damage to the device
The device is not working as specified
The device has been stored under unsuitable conditions for an extended period of time.
If there is any doubt, please return the device to the manufacturer for repair or maintenance.
6. Customers must not attempt to alter or repair the device themselves. If the instrument is opened or
attachment parts are released, its trouble-free operation and reliability is impaired and endangers
the operator. Please return the device to the manufacturer for any repair or maintenance.
7. There must be used only the original sealings in the device.
8. Any operation not included in the following instructions or outside the specifications must not be
attempted.

Pressure Balance GB
CPB 3000
WIKA Operating Instructions Pressure Balance Version 1.1 6
2. Product Description .
2.1 General Product Information .
Application
Pressure balances are the most accurate instruments for the calibration of electronic or mechanical
pressure measuring instruments. The direct measurement of pressure, according to its definition as a
quotient of force and area, and the use of high-quality materials result in small uncertainties of
measurement and an excellent long-term stability of five years.
For these reasons pressure balances have already been used in calibration laboratories of industry,
national institutes and research labs for many years. Due to the integrated pressure generation and
the purely mechanical measuring principle the CPB 3000 is also ideally suited for on-site use as well
as service and maintenance purposes.
Piston/cylinder measuring system
Pressure is defined as a quotient of force and area. Correspondingly, the core of the CPB 3000 is a
very precisely manufactured piston/cylinder system. Both the piston and cylinder are manufactured
from Tungsten Carbide and are very well protected in a solid stainless steel housing against touching,
impacts or contamination from outside.
The entire construction design of the piston/cylinder unit and the very precise manufacturing of the
piston and the cylinder stand for excellent operating characteristics with a long free rotation time and
low fall rates and for a very high long term stability. Therefore the recommended re-calibration interval
is 5 years.
The hydraulic systems are available for measuring ranges from 60 bar up to 1,000 bar resp. 1,000 psi
up to 14,500 psi. The accuracy is 0.025 % of reading.
Functioning
In order to generate the individual test points, the piston cylinder system is weighted with mass-loads.
The weight applied is proportional to the desired pressure and provided by using optimally graduated
weights. These weights are manufactured to standard gravity (9.80665 m/s²) although for fixed
location usage they can be adjusted to a customer specified local gravity.
The pressure is set via an integrated fine-adjustable precision spindle pump. As soon as the
measuring system reaches equilibrium, there is a balance of forces between pressure and mass
applied.
Due to the high-grade quality of the system this pressure remains stable over several minutes, so that
for instance adjustments of your device under test can be carried out without any problems.

Pressure Balance GB
CPB 3000
WIKA Operating Instructions Pressure Balance Version 1.1 7
2.2 Basic principle of the Pressure Balance .
Their operating principle is based on the physical definition of pressure, the quotient of force and
surface.
Area
Force
essure =Pr
The key element of the pressure balance is a precision-manufactured piston/cylinder system with a
precisely measured cross-sectional surface.
To apply a pressure charge to the system, the piston is placed under a load with (calibrated) weight
pieces.
Each holding disk from the set of weights is identified by a nominal weight, which generates a
pressure value in the system (assuming standard reference conditions). Each weight has a number
and in the calibration certificate there is described the mass value to each weight with its resultant
pressure value. The weights are chosen according to the desired pressure value.
After that, the integrated spindle pump increases the pressure until the weights are in a floating state.
2.3 Factors at work .
The piston pressure gauge is calibrated to standard reference conditions when it leaves the factory
(depending on customer specifications).
If there are significant deviations between the application conditions and the defined reference
conditions, appropriate corrections must be made.
Following are the main factors that enter into play and must be considered.
These corrections can be made automatically with the CalibratorUnit CPU 5000
(see accessories point 8)!
2.3.1 Local fluctuations in the gravity-value .
The local force of gravitation is subject to major fluctuations caused by geographical variation.
The value may differ from one place on earth to another by as much as 0.5 %. Since this value has a
direct effect on the measurement, it is essential that it be taken into consideration.
The weight pieces can even be adjusted during manufacturing to match the location where they will be
used. Another option, especially if the device will be used at multiple locations, is to perform a
calibration to the standard gravity,
"Standard-g = 9.80665 m/s2".
Then a correction must be performed for each measurement according to the formula below:
gdardS sitenApplicatiog
pressureTrue −
−
⋅= tan
valueNominal
Example:
Local gravity set during manufacturing: 9.806650 m/s2
Locale gravity at application site: 9.811053 m/s2
Nominal pressure: 100 bar
True pressure: barbar
gg
pp
dardS
Local 0449.100
80665.9 81105.9
100
tan
Nominal ===
Without the correction, measurements would all be "off" by 0.05 %.

Pressure Balance GB
CPB 3000
WIKA Operating Instructions Pressure Balance Version 1.1 8
2.3.2 Temperature (Piston/Cylinder) .
The effective cross-sectional surface of the piston/cylinder system depends on the temperature.
The effect depends on the material used and is described by the temperature coefficient (TK).
In the event of deviations from standard reference conditions (typically 20°C), the following formula
must be used to make a correction:
()()
TKtt
pressureTrue
ferenceAppl ⋅−+
⋅=
Re
11
valueNominal
Example:
Reference temperature: 20°C
Temperature during use: 23°C
TK: 0.0022%
()
()
barbarpressureTrue 99340.99
2.220231 1
100 5=
⋅−+
⋅= −
Without the correction, measurements would all be "off" by 0.007 %.
2.3.3 Ambient conditions .
The effects of ambient conditions
air pressure
room temperature
relative humidity
should always be taken into consideration if the highest level of accuracy is required.
Fluctuations in ambient conditions change air density.
The air density affects the pressure through the buoyancy of the weights:
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛−⋅= densityWeight
densityAir
Weight 1weightNominal
The air density is typically 1.2 kg/m3
The density of the weights (non-magnetic steel) is 7900 kg/m3
A fluctuation of 5% in the relative humidity causes an additional uncertainty in the measurement of
about 0.001%.

Pressure Balance GB
CPB 3000
WIKA Operating Instructions Pressure Balance Version 1.1 9
2.3.4 How the cross-sectional surface responds to pressure .
At higher pressures, the effective cross-sectional surface changes due to the pressure load.
The ratio of the cross-section and prevailing pressure is linear within an initial approximation. It is
represented by the coefficient of expansion caused by pressure distortion (λ).
pressureNominal1 pressureNominal ⋅+
=
λ
pressureTrue
Example:
Measuring point: 1000 bar
System with distortion coefficient: 10 –7 1/bar:
barbarpressureTrue 90.999
10001011 1000
7=
⋅
⋅
+
=−
Without the correction, measurements would all be "off" by 0.01 %.

Pressure Balance GB
CPB 3000
WIKA Operating Instructions Pressure Balance Version 1.1 10
2.4 Arrangement of control elements .
View from above
Front view
Side view
Connection for
test specimen
Spindle pump
Connection for
piston/cylinder
system
Water level
Removable star
handle with spring-
loaded thrust pad
Piston/cylinder
system
Rotating base
Reservoir with
Shut-off valve
Shut-off valve for
test connection
Storage for
weight pieces