DH-Budenberg CPB3500 Specifications

Pneumatic dead-weight tester
Model CPB3500

Applications

■

Primary standard for calibrating the pressure scale in a
pneumatic range from -1 ... 120 bar / -14.5 ... 1,600 psi

■

Reference instrument for factory and calibration

laboratories for the testing, adjustment and calibration of

pressure measuring instruments

■

Complete, stand-alone system, also suitable for on-site use

Special features

Calibration technology

WIKA data sheet CT 31.22

■

Total measurement uncertainty starting from

0.015 ... 0.006 % of reading

■

Five dierent piston-cylinder systems available for
ranges ±1 bar, 0.1 ... 7 bar, 0.2 ... 25 bar, 1 ... 70 bar and
1 ... 120 bar, or also for ranges in psi and kPa

■

Stable aluminium base with a strong impact-resistant ABS
cover for heavy industrial use combined with compact
dimensions and light weight

■

Interchangeable pistons and mass sets for each model,

mass sets manufactured from stainless steel

■

Factory calibration includes traceability to national

standards, as standard; with UKAS calibration possible as

an option

Description

Proven primary standard

The model CPB3500 dead-weight tester is a genuine
primary standard, which derives the measurement of
pressure directly from its fundamental equation p = F/A.

This mechanical measurement principle provides superior

reliability and stability over time, eliminates most risks of

measurement error and reduces calibration uncertainties. It

makes the CPB3500 the ideal tool for the calibration of any

type of pressure measuring instruments on a daily basis.

Robustness and modularity

The instrument is built on a tough, stable aluminium base

with light weight corrosion and impact-resistant ABS case.
Piston cylinders are interchangeable among the various

models within the CPB3500, so that in case of changing
requirements any CPB3500 tester can easily be upgraded on

other available ranges.

Pneumatic dead-weight tester, model CPB3500

Mass sets are fully interchangeable between pistons of the
same range within the claimed standard accuracy. The mass
set is made of non-magnetic stainless steel so that masses
remain extremely stable over time.
Bases can also be quickly converted into a comparator by
substituting suitable transfer standard for the piston and
mass set.

Ease of operation

Two built-in precision soft seat valves combined with a

volume adjuster provide ne pressure control capability. A
safety pattern gauge is tted to the instrument base to show

the approximate pressure. The masses are top loading
(except on the 25 bar/400 psi range) for easier and faster
operation and available in the most common pressure units.

Data sheets showing similar products and accessories:

Dead-weight tester in compact design; model CPB3800; see data sheet CT 31.06
Pressure balance; model CPB5000; see data sheet CT 31.01
Pressure balance for high pressure; model CPB5000HP; see data sheet CT 31.51
Pressure balance dierential pressure version; model CPB5600DP; see data sheet CT 31.56
CalibratorUnit; model CPU6000; see data sheet CT 35.02

Page 1 of 9WIKA data sheet CT 31.22 ∙ 03/2015

The mass load is proportional to the target pressure and
this is achieved through optimally graduated disc weight. As

standard, these disc weights are manufactured to the stand-
ard gravity (9.80665 m/s²), though they can be adjusted to a
specic location and also UKAS calibrated.

The piston-cylinder system

Both the piston and cylinder are manufactured from materials
with very small pressure and thermal expansion coecients,
which results in a very good linearity of the eective area of
the piston and thus a high measurement accuracy.

An overpressure protection is integrated, which prevents the
piston from being forced out vertically and avoids damage
to the piston-cylinder system in the event of disc weights
removal under pressure.

The piston and cylinder are clean air/gas only systems apart
from the 70 bar/1,000 psi and 120 bar/1,600 psi ranges

where the piston-cylinder system is oil lubricated.
The masses are stacked on the piston-cylinder system apart

from the 25 bar/400 psi range, where the annular masses are

stacked on a mass carrier, so as to have minimum side thrust
and friction on the piston-cylinder system.

The overall design of the piston-cylinder system and the very
precise manufacturing of both the piston and the cylinder
ensure excellent operating characteristics with a long
free-rotation time, low sink rates and a very high long-term

stability. Therefore, the recommended recalibration interval is
two to ve years dependent on the conditions of usage.

As a standard all instrument bases are equipped with a G 1
female thread as connection for the piston-cylinder system.

Force F

Eective area A

Pressure p

Piston-cylinder system model CPS3500

Tables of masses

The following tables show, for the respective measuring
range, the number of masses within a mass set, with their

resulting nominal pressures.

Should the instrument not be operated under reference

conditions (ambient temperature 20 °C/68 °F, atmospheric
pressure 1,013 mbar/14.69 psi, relative humidity 40 %), the
relevant corrections must be made, for example with the
CPU6000 CalibratorUnit, see page 8.

Page 2 of 9 WIKA data sheet CT 31.22 ∙ 03/2015

The disc weights are manufactured, as standard, to the

standard gravity (9.80665 m/s²) although they can be
adjusted for any local gravity.

Measuring range

1)

[bar]

Piston and make-up weight 1 0.015 1 0.1 1 0.2 1 1 1 1

Standard mass set

Set of ne increment masses

(optional)

0.015 ... 1 0.1 ... 7 0.2 ... 25 1 ... 70 1 ... 120

Quan­tity

1 0.005 1 0.4 1 0.3 2 1 2 1

3 0.02 2 0.5 1 4.5 5 10 1 18

2 0.01 5 1 3 5 1 9 4 20

6 0.05 2 0.2 2 2 2 4 1 10

6 0.1 1 0.1 1 1 1 2 2 4

- - 1 0.05 1 0.5 1 0.5 1 2

- - - - - - - - 1 0.5

- - 2 0.02 2 0.2 1 0.4 1 0.4

- - 1 0.01 1 0.1 1 0.2 1 0.2

- - 1 0.005 1 0.05 1 0.1 1 0.1

- - - - 2 0.02 2 0.04 2 0.04

- - - - 1 0.01 1 0.02 1 0.02

Nominal
pressure
per piece

Quan­tity

Nominal
pressure
per piece

Quan­tity

Nominal
pressure
per piece

Quan­tity

Nominal
pressure
per piece

Quan­tity

Nominal
pressure
per piece

Measuring range

1)

[psi]

Piston and make-up weight 1 1 1 3 1 10 1 10

Standard mass set

Set of ne increment masses

(optional)

Measuring range

1)

[kPa]

Piston and make-up weight 1 1.5 1 10 1 20 1 100 1 100

Standard mass set

Set of ne increment masses

(optional)

1) Other ranges like “in. water” and “mm. water” also available on request.

1 ... 100 3 ... 400 15 ... 1,000 10 ... 1,600

Quantity Nominal

pressure per
piece

1 4 1 7 2 10 2 10

2 5 1 90 1 180 1 180

5 10 2 100 3 200 6 200

2 2 1 50 1 100 1 100

1 1 2 20 2 40 2 40

1 0.5 1 10 1 20 1 20

- - 1 5 1 5 1 5

2 0.2 2 2 1 0.4 1 0.4

1 0.1 1 1 1 0.2 1 0.2

1 0.05 1 0.5 1 0.1 1 0.1

- - 2 0.2 2 0.04 2 0.04

- - 1 0.1 1 0.02 1 0.02

Quantity Nominal

pressure per
piece

Quantity Nominal

pressure per
piece

Quantity Nominal

pressure per
piece

1.5 ... 100 10 ... 700 20 ... 2,500 100 ... 7,000 100 ... 12,000

Quan­tity

1 0.5 1 40 1 30 2 100 2 100

3 2 2 50 1 450 5 1,000 1 1,800

2 1 5 100 3 500 1 900 4 2,000

6 5 2 20 2 200 2 400 1 1,000

6 10 1 10 1 100 1 200 2 400

- - 1 5 1 50 1 50 1 200

- - - - - - - - 1 50

- - 2 2 2 20 1 40 1 40

- - 1 1 1 10 1 20 1 20

- - 1 0.5 1 5 1 10 1 10

- - - - 2 2 2 4 2 4

- - - - 1 1 1 2 1 2

Nominal
pressure
per piece

Quan­tity

Nominal
pressure
per piece

Quan­tity

Nominal
pressure
per piece

Quan­tity

Nominal
pressure
per piece

Quan­tity

Nominal
pressure
per piece

Page 3 of 9WIKA data sheet CT 31.22 ∙ 03/2015