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FURNESS CONTROLS
Primary pressure standard FRS4
Used in laboratories worldwide, the Furness Controls Reference Standard (FRS4) is a high-resolution, low-pressure standard directly traceable to national standards via mass and linear measurement. The instrument is the gold standard for gauge and differential pressure calibration. Its unique design allows high levels of accuracy at very low pressure levels, in the range where competing instruments begin to experience uncertainty.
- Pressure calibration range from 0.001 Pa to 44 kPa
- Typical uncertainty of ±0.005% of reading + 0.02 Pa
- Optionally available with a controller for automated calibrations
Used in laboratories worldwide, the Furness Controls Reference Standard (FRS4) is a high-resolution, low-pressure standard directly traceable to national standards via mass and linear measurement. The instrument is the gold standard for gauge and differential pressure calibration. Its unique design allows high levels of accuracy at very low pressure levels, in the range where competing instruments begin to experience uncertainty.
Producing standardized pressure requires precise knowledge of the metrics of the physical components involved. The FRS4 uses a regulated air flow over a piston with precisely known mass and dimensions, a high-precision digital scale, and a precision control unit. With these components, the FRS4 is able to generate accurate differential pressure for use in calibrating a multitude of devices, such as capacitance diaphragm gauges and low-pressure transmitters and sensors.
Precise construction
The piston is suspended centrally in a cylinder using a parallelogram suspension system, and both are precision-made from Invar, a nickel-iron alloy with a low coefficient of thermal expansion. This gives a surface expansion coefficient at room temperature of approximately 4 ppm.
Friendly
To complement the FRS4 pressure standard, the FCS476 control unit can be used to provide automatic pressure control from a PC.
By using the shock resistant carrying case, the FRS4 is easily transportable, making it useful for inter-comparison between pressure standards with which they are not so easily movable.
