Series 7250

Ruska Pressure
Controller/Calibrator

Technical DataFeatures• Pressure ranges from 0 to 5 and 0 to3 000 psi (0 to 35 kPa and 0 to 21 MPa)
• Model 7250xi and 7250i provide advanced
precision of 0.005 % of reading• Model 7250 provides 0.003 % of full scaleprecision• Stability: 0.0075 % of reading per year
• Time to setpoint: 20 seconds with noovershoot• Control stability: 10 ppm• Active matrix color screen with enhanced
navigation menus•		Languages: English, French, Chinese,German, Japanese, Spanish and Italian

The Series 7250 high speed digital pressure
controllers represent the fifth generation ofautomatic pressure controllers from Fluke Calibration and offers unmatched performance, anactive matrix color screen and enhanced control
stability. Utilizing multiple sensors and ranges ina single instrument, the Series 7250 combines
precision, stability, speed and affordability.
Models 7250xi, 7250i and 7250, up to
2 500 psi (17.2 MPa), use a unique quartz
sensor, the most accurate pressure sensing
technology in a pressure calibrator. Each quartz
sensor is manufactured and tested to providethe ultimate performance required by a Fluke
Calibration pressure calibrator, ensuring thatevery customer receives quality, precision andstability in their instrument.

unmatched precision is achieved through uniquequartz pressure sensing technology and multiple quartz sensors in a single instrument. The
7250xi is available with any full scale range
from 20 to 2 500 psi (140 kPa to 17.2 MPa). The
Model 7250i provides 0.005 % of reading from40 % to 100 % of range and is available withany full scale range from 5 to 2 500 psi(35 kPa to 17.2 MPa).
For pressure below the lower threshold of
20 % for the 7250xi and 40 % for the 7250i, theprecision becomes 0.005 % of the lower value.
For example, a 1 000 psi (7 MPa) Model 7250xi
provides 0.005 % of reading from 200 to 1 000
psi (1.4 MPa to 7 MPa); the precision for pressures from 0 to 200 psi (0 to 1.4 MPa) is 0.005 %of 200 psi (1.4 MPa).
Selecting the full scale range of the 7250xi
Advanced precisionand 7250i to purchase is simplified with thepercent of reading capability. Simply deterModels 7250xi and 7250i offer advanced percent of reading precision for increased capability mine the highest pressure required and thendecide if 0.005 % of reading is required downwith a single instrument, reducing the investto 40 % or 20 % to maintain the appropriate
ment required to calibrate a wide variety ofpressure devices and ranges. The Model 7250xi calibration ratio. The complex analysis associated with selecting the appropriate single orprovides 0.005 % of reading precision frommultirange instruments with percent of full
20 % to 100 % of the instrument’s range. Thisscale performance is no longer required. And,
since the performance of the 7250xi and 7250i
is continuous throughout the range, the time
consuming task of controlling to atmosphere andswitching ranges is eliminated.
The 7250xi and 7250i not only provide
unequalled precision, but also excellent longterm stability due to the inherent properties ofquartz in combination with several enhancements implemented over the last few years. The
total uncertainty of the 7250xi and 7250i overa one year calibration interval is 0.009 % ofreading down to 20 % and 40 %, respectively.
Simplified specifications eliminate guesswork
and “specmanship” to allow you to determine
the actual performance delivered with everyinstrument.

Standard precision
For applications that do not require the level ofperformance provided in the 7250xi or 7250i,
the Model 7250 offers an economical approach
to automatic pressure testing and calibration
with a precision of 0.003 % of full scale forranges to 2 500 psi (17.2 MPa).

High pressure precision
For applications that require pressures up to
3 000 psi (21 MPa), the Model 7250HP provides
total uncertainty (one year calibration interval)of 0.013% of reading down to 30% of the fullscale. The 7250HP provides the high speed
control and performance of the standard 7250
with a full scale pressure range of 3 000 psi(21 MPa) absolute.

High-speed pressure
control
All Series 7250 instruments
up to 2 500 psi (172 bar) reach
setpoint in 20 seconds or lessinto a 15 cubic inch (245 cc)volume, with no overshoot, toallow high-speed pressure test
and calibration.

Dual control modes
The Series 7250 features a unique fusedquartz sensor. This rugged transducer offers
unequalled precision and a stability of0.0075 % of reading per year.

2 Fluke Calibration

The Series 7250 also provides
two user-selectable control
modes: active and passive

Series 7250 Ruska Pressure Controller/Calibrator

mode. In active mode, the 7250 is continually
maintaining the setpoint and can compensate
for small leaks and pressure changes due totemperature. In passive mode, the user definesa control band and the 7250 will turn off thecontroller once it achieves the setpoint within
the control band. In a leak-free and temperature-stable system, passive mode contributes
no additional uncertainty, providing optimum
performance.

Automating pressure test andcalibration
The 7250xi, 7250i and 7250 are easy to use andcan automate your calibrations in several ways:
Step up/down: for calibrations where theincrements are fixed intervals, enter a userdefined step value. The Series 7250 increases
or decreases the pressure by the step amountwith the jog dial—no more lengthy keystroke
sequences to program.
Sweep test: for simple exercising routines,
as with dial gauges, enter a start value, a stopvalue, and number of times to repeat the cycle.
The Series 7250 will automatically exercise thedevice under test prior to the calibration run.
Onboard programs: For frequently used or
lengthy calibrations, the Series 7250 can store
up to 20 user-defined programs/profiles with up
to 1000 steps total in internal memory.
Computer interface: Every Series 7250 isprovided with both an RS-232 and IEEE-488
interface, and Series 7250 syntax follows SCPI
protocol for easy programming. COMPASS®,
an off-the-shelf software package is available in addition to the LabVIEW® driver, a freedownload and optional MET/CAL® driver. Asa standard feature, software written for theprevious generation Series 7215, 7010 and 6000
instruments is fully supported by the Series
7250. The Series 7250 can also be set to 510
emulation mode to use software originally written for the DPI 510. Firmware updates can also
be performed over the RS-232 interface.

Versatility to handle any pneumaticpressure calibration
The Series 7250 is versatile enough to handle
almost any type of pneumatic pressure
calibration.
Wide pressure range: available with any fullscale pressure between 5 and 2 500 psi (35 kPa
and 17.2 MPa) or for higher pressures select the
3 000 psi absolute (21 MPa) range.

Pressure units/scales: Select from overtwelve standard units of measure, including
inHg at 0 °C and 60 °F, kPa, bar, psi, inH2O at
4 °C, 20 °C and 60 °F, kg/cm2, mmHg at 0 °C,cmHg at 0 °C, and cmH2O at 4 °C, and two userdefined units.
Head pressure: Automatic correction for headpressure differences
Absolute mode: The 7250i and 7250 offer
three different methods to make absolute pressure measurements. The barometric reference
option provides the most convenient method
and is available on ranges 15 psi (1.0 bar) andhigher. Alternatively, the vacuum reference
option allows the connection of an external
vacuum pump to the reference port of theinstrument. An onboard vacuum sensor monitors
the reference vacuum and allows for automatic
zeroing in absolute mode. This option provides
the lowest overall uncertainty since it does notinclude the additional uncertainty of a secondary barometric reference sensor. For pressure to50 psia (350 kPa) permanent absolute models
are also available. The 7250xi is only available
with the barometric reference option for absolute measurement.
Autovent and autozero: With few keystrokes,
the Series 7250 will vent the test port to atmosphere or automatically zero itself (autovent is
not applicable to permanent absolute models).
Protection of the device under test: Set
upper and lower pressure limits to ensure
protection of the device under test.

Options
The Series 7250 can be provided for gauge
mode operation, or with:• Optional vacuum (negative gauge) mode forbidirectional devices• Optional barometric reference for absolutemode calibrations• Permanent absolute ranges to 50 psia (350kPa) full scale which include a tare feature forsimulated gauge mode operation
The Series 7250 Pressure Controller/Calibrator
can easily automate your test and calibration
workload. All are easy to use, easy to maintain, and have the reliability, performance andfeatures that you want. The Series 7250 features
an easy-to-navigate menu structure with fulltext descriptions for menus and commands.

3 Fluke Calibration

Series 7250 Ruska Pressure Controller/Calibrator

The large color display allows the pressure value to be displayed evenwhen viewing a submenu selection such as the units selection screen
shown above.

All Series 7250s are fully programmable and can store up to 20
separate programs with up to 1000 steps.

Specifications
General

Total Uncertainty (k=2)2

Temperature

Operating: 18 °C to 36 °C (64 °F to 96 °F)
Storage: -20 °C to 70 °C (-4 °F to 158 °F)

Humidity

5 % to 95 % RH, non-condensing

WeightModel 7250/7250i: 7.7 kg (17 lb)
Model 7250xi: 9 kg (20 lb)

Dimensions (H x W x D)

All versions: 178 mm x 419 mm x 483 mm (7 in x 16.5 in x 19 in)Pressure medium

Nitrogen or clean dry air

Display

TFT, VGA, active matrix, 162.5 mm (6.4 in) 640 x 480 resolution, 65,000 colors

Test port and supply
connection

1/4 in NPT female

Warm up time

24 hours; may be left on indefinitely

Model 7250xi

20 % to 100 % FS
90 day: 0.006 % reading
1 year: 0.009 % reading

Model 7250i

40 % to 100 % FS
90 day: 0.006 % reading
1 year:0.009 % reading

Model 7250

90 day: 0.003 % FS + 0.002 % reading
1 year: 0.003 % FS + 0.0075 % reading

Model 7250HP

30 % to 100 % FS
90 day: 0.012% reading
1 year: 0.013% reading

Control parameters

Pressure ranges

Volume82 cm to 980 cm (5 in3 to 60 in3)

Model 7250xi

Any Full Scale pressure range from 20 psig to 2 500 psig (140 kPa to17.2 MPa).

Low Control (absolute)

0.15 psia (1 kPa)

Model 7250i

Any Full Scale pressure range from 5 psig to 2 500 psig (35 kPa to 17.2 MPa).
Or, Permanent Absolute ranges from 15 psia to 50 psia (100 kPa to 350 kPa
absolute).

Communications

Model 7250

Any Full Scale pressure range from 5 psig to 2 500 psig (35 kPa to 17.2 MPa).
Or, Permanent Absolute ranges from 15 psia to 50 psia (100 kPa to 350 kPa
absolute). For ranges below 35 kPa (5 psi), see the 7250LP.

MET/CAL® driver

Optional

LabView® driver

Optional

Absolute using barometric reference sensor for ranges from 15 psig to2 500 psig (100 kPa to 17.2 MPa)

Firmware updates are performed via RS-232 interface
Languages

Vacuum (negative gauge)

The Series 7050 is capable of displaying menus and functions in:English, French, Chinese, German, Japanese, Spanish and Italian

Optional modes

RS-232 and IEEE-488, SCPI syntax. Series 7215, Model 7010, Series
6000 and DPI 510 emulation are standard.

Vacuum reference (requires external vacuum pump)
Model 7250HP

Options

3000 psi absolute (21 MPa absolute)

Barometric reference (absolute and vacuum)
Vacuum mode (negative gauge)
Vacuum reference (requires external vacuum pump)

Performance
Precision 1

Stability

Model 7250xi: From 20 % to 100 % full scale (FS): 0.005 % of reading
Below 20 % FS: 0.005% of 20 % FS
Model 7250i: From 40 % to 100 % FS: 0.005 % of reading
Below 40 % FS: 0.005 % of 40 % FSAccessories
3911197

Transportation Case with Wheels and Handles

Model 7250: Ranges to 2 500 psi (17.2 MPa): 0.003 % of FS

3879677

Rack mount kit for 19 in. EIA cabinets, 24 in. deep

Model 7250HP: 0.012% of reading or 0.0036% FS, whichever is greater

3879689

Rack mount kit for 19 in. EIA cabinets, 30 in. deep

Ranges 2 500 psi (17.2 MPa): 0.0075 % of reading per year
3 000 psia (21 MPa) range: 0.005% of reading

3876298

Lines and Fittings Kit

4014713

Vacuum Pump with auto-vent, 85 liters/minute3876271

Liquid Trap

3891089

MET/CAL Pseudo-Driver3070175

COMPASS for Pressure Enhanced, Single License

Control stability

Active mode: 0.001 % FS (10 ppm)
Passive mode: no additional uncertainty

Display resolution

User selectable to 1:1,000,000

Control response

20 seconds or less with zero overshoot into a 245 cm (15 in3) volume for ranges
to 2 500 psi (17.2 MPa)

Negative gauge
precision (optional)

Model 7250i

Uncertainty (2 sigma)

60 seconds for 3 000 psia (21 MPa) range

Precision

0.005 % of reading

Model 7250xi: 0.005 % of 20 % FS or 0.00075 psi (0.05 kPa), whichever isgreater

Stability (one year)

0.0075 % of reading

Calibration standard

0.0010 % of reading

Model 7250i: 0.005 % of 40 % FS or 0.0075 psi (0.5 kPa), whichever is greater

Environmental temperature(included in precision)

0.000 % of reading

Head pressure

0.001 % of reading

Expanded uncertainty (2sigma)

0.009 % of reading

Model 7250: 0.003 % of FS
Model 7250HP: Not applicable
Barometric reference(optional)

0.002 psi (0.014 kPa) maximum error per year

Vacuum reference(optional)

0.0002 psi (0.0014 kPa) maximum error per year (Only available on 7250iand 7250)

Calibration

1

P recision is defined as the combined effects of linearity, repeatability
and hysteresis throughout the operating temperature range.
Total uncertainty is the maximum deviation from the true value ofpressure including precision, stability, temperature effects and thecalibration standard. This assumes routine zeroing of the instrument.
Expression of uncertainty conforms with the recommendations of theISO Guide to the Expression of Uncertainty in Measurement.

2An accredited calibration report is provided standard. For information on the calibration uncertainty,
please see the appropriate Fluke Calibration Scope of Accreditation.

Fluke Calibration. Precision, performance, confidence.™

Fluke Calibration
PO Box 9090, Everett, WA 98206 U.S.A.
Fluke Europe B.V.
PO Box 1186, 5602 BD
Eindhoven, The Netherlands

4 Fluke Calibration

Series 7250 Ruska Pressure Controller/Calibrator

For more information call:In the U.S.A. (877) 355-3225 orFax (425) 446-5116
In Europe/M-East/Africa +31 (0) 402675 200 or Fax +31 (0) 40 2675 222
In Canada (800)-36-FLUKE or
Fax (905) 890-6866

From other countries +1 (425) 446-5500 or
Fax +1 (425) 446-5116
Web access: http://www.flukecal.com©2010, 2021 Fluke Corporation.
Specifications subject to change without notice.
Printed in U.S.A. 8/2021 210879 3833773C D-EN-N
Modification of this document is not permitted
without written permission from Fluke Corporation.