2465A Gas Piston Gauge

Key features

Ranges from 1.4 kPa to 7 MPa.
Accuracy: Up to 0.0010% for pressures to 700 kPa, 0.0027% for pressures over 700 kPa to 7 MPa.
Precision & Stability: Better than 3 ppm, with a resolution of 0.0001% or 1 mg.
Gauge, absolute, vacuum, and low pressure modes.

Product overview: 2465A Gas Piston Gauge

The Fluke Model 2465 Gas Piston Gauge (formerly Ruska 2465) has a long history of serving national standards laboratories, commercial industry and government organizations as a primary pressure standard for over 40 years. Since its original introduction, enhancements have been made to increase performance and reduce operator workload.

The Model 2465 provides the capability of generating pressures to within a total expanded uncertainty of 10 parts per million to 700 kPa (100 psi) and 26 parts per million to 7 MPa (1000 psi). The Model 2465 is available in a variety of configurations to meet individual requirements. The three basic components of the Model 2465 are the Instrument Base, one or more Piston/ Cylinder Assemblies, and a single Mass Set.

Instrument base

The instrument base is designed with functionality, economy and space conservation in mind. All electronic components are housed away from the instrument base to eliminate errors caused by thermal effects and magnetic fields. The thermally isolated motor drive is connected to the cylinder— eliminating pressure fluctuations and maximizing productivity. A durable, acrylic bell jar is provided to allow absolute and vacuum modes of operation. A KF16 fitting is provided to simplify installation and allow low reference pressures.

Piston/cylinder assemblies

Piston and cylinder assemblies are manufactured from proven materials that have evidenced superior strength, durability, low distortion, low thermal coefficients and virtually undetectable hysteresis over the last several decades, and have an unparalleled record of long-term stability. Tungsten carbide is used for all pistons and cylinders, except where the demand for accurate low pressures is met by using high quality stainless steel (low range piston). The lower density of steel facilitates generating pressures down to 0.2 psi (14 mbar). Four piston/cylinder combinations are now available to generate pressures over the total range of the system. The maximum sink rate for each piston/cylinder is 0.38 centimeters/ minute (0.15 inches/minute). If lower sink rates are required, please refer to the Model 2468 Gas Piston Gauge.

Mass set

Each mass is machined to a nominal value and is made from non-magnetic materials to provide long-term stability and eliminate sensitivity to magnetic fields. For ease of use, the entire mass set totals just 6 kilograms, with a maximum platter mass of 1 kilogram. A laboratory grade trim mass set is included to allow any pressure increment within the range and resolution of the piston/cylinder assembly.

Manual pressure control

For manual operation, the Model 2465 can be provided with a manually operated Pressure Control Pack, for regulating and controlling the system pressure and float position. The optional Model 2456 Piston Gauge Monitor and WinPrompt software add further capability to the manual system (see separate Model 2456 data sheet for additional information and specifications).

Operating modes

The Model 2465 is capable of operating in gauge, absolute and vacuum mode.

Gauge mode: pressure is achieved by simply loading the appropriate mass load to the top of the piston.

Absolute mode: A vacuum pump can be connected to the reference pressure port, using standard KF16 vacuum fittings. The appropriate mass load is applied and the bell jar is placed on the instrument base. The vacuum pump evacuates the bell jar and the residual amount of pressure is measured with the Model 2456 Deadweight Gauge Monitor.

Accessories

Model 2456 Piston Gauge Monitor and WinPrompt software: For users who do not require the autofloat capability, but want to add a level of automation to the Model 2465. The Model 2456 continuously monitors piston temperature, float position, and sink rate, and optionally air density and reference vacuum. WinPrompt software calculates mass-to pressure and pressure-to-mass values, and automatically reads and displays real-time piston gauge parameters.

Lines and fittings kits: Lines and fittings kits are available to ensure that you have all the components needed to install the system and begin performing calibrations.

Vacuum pumps: For applications where absolute or vacuum mode calibrations will be performed, two vacuum pumps are required. Each pump should have a minimum capacity rating of 85 liters/minute and achieve an ultimate total pressure of 2E-03 mbar (1.5E-03 Torr). Fluke Calibration can provide high quality vacuum pumps that meet these requirements. Fluke Calibration supplied pumps also include a backstream filter to prevent contamination of the Model 2465 and device under test along with a muffler for quiet operation.

Specifications: 2465A Gas Piston Gauge

General
Pressure range	Gauge mode: 1.4 kPa to 7 MPa (0.2 to 1000 psi) gauge Absolute mode: 1.4 kPa to 7 MPa (0.2 to 1000 psi) Vacuum mode: -100 to 0 kPa (-14.5 to 0 psi) gauge (Vacuum pressure achieved depends on local barometric pressure)
Electrical power	115/230 VAC, 50/60 Hz, 15 W
Temperature	Operating temperature 15 to 28°C (60 to 82°F) Storage temperature -20 to 70°C (-4 to 158°F)
Humidity	Operating humidity 20–75% relative humidity, noncondensing; storage humidity 0–90%
Pressure medium	High purity nitrogen or dry, clean air with less than 0.5 ppm hydrocarbon and less than 5 ppm H2O content, dew point less than or equal to -50 °C, and less than 50 micron particulate size. Although lower quality gas can be used, the frequency of piston/cylinder cleaning will increase.

Performance
Precision (type A uncertainty)	Better than 3 ppm Values are reported at the 95% confidence level (2σ)
Long-term stability	Better than 1.5 ppm per two years Values are reported at the 95% confidence level (2σ)
Resolutionc	1 ppm or 1 mg

Piston/Cylinder Assemblies
Low Range	Nominal area: 0.52 in2 (3.4 cm2) Pressure range: 0.2–25 psi (14 mbar to 1.7 bar) Total uncertainty: 0.001% RDG or 0.00001 psi (threshold pressure 1 psi)c Materials: Piston is 440C stainless steel, cylinder is cemented tungsten carbide Thermal coefficient: 1.5E-05/°C
Lower Mid Range	Nominal area: 0.13 in2 (0.84 cm2) Pressure range: 1.7–100 psi (117 mbar to 7 bar) Total uncertainty: 0.001% RDG or 0.00004 psi (threshold pressure 4 psi)c Materials: Piston and cylinder are cemented tungsten carbide Thermal coefficient: 9.1E-06/°C
Upper Mid Range	Nominal area: 0.026 in2 (0.168 cm2) Pressure range: 2–500 psi (0.14 to 35 bar) Total uncertainty: 0.0026% RDG or 0.0004 psi (threshold pressure 16 psi)c Materials: Piston and cylinder are cemented tungsten carbide Thermal coefficient: 9.1E-06/°C
High Range	Nominal area: 0.013 in2 (0.084 cm2) Pressure range: 2–1000 psi (0.14 to 70 bar) Total uncertainty: 0.0026% RDG or 0.0004 psi (threshold pressure 16 psi)c Materials: Piston and cylinder are cemented tungsten carbide Thermal coefficient: 9.1E-06/°C

Mass Set
Total mass	13.2 lb (6 kg)
Maximum platter mass:	2.2 lb (1 kg)

Computer Interface
Requirements	Pentium level processor, RS-232C interface, monitor, mouse or other pointing device, keyboard; program requires 2MB available hard disk space; Windows 95 or higher