AMETEK Products




Primary low pressure standards 

U-tube manometers for relative and absolute pressures, vacuum and differential pressures.
These devices are primary standards and are void of faults within their physical tolerances. They are designed to measure pressure and are suitable for calibrating high precision pressure sensors.
  • Very low maintenance cost. No need for recalibration
  • No electronic parts. Can be used anywhere
  • Traceable calibration certificate
  • Ideal for calibration of transmitters in clean-room applications
  • Differential pressure for flow applications
  • Baroscope for absolute pressure in metrology laboratories and aerospace applications
  • Calibration of handheld instruments used in HVAC applications

Basic knowledge
U-tube manometers of this type are primary standards. The measuring principle of these liquid manometers is based on the following relationship:
dp=dh x pm x g
The pressure (p) to be measured is to be compared with the height (h) of a liquid column. If the pressure exerted on the two surfaces of the so-called confined liquid is not the same, there is a deflection and consequently a difference in height. The confined liquid continues to rise until the effect of the force of the pressure differentials and the weight of the liquid columns are identical. In accordance with the laws of physics, the effect of the liquid column on the pressure in the liquid is, in essence, only dependent on height (h) of the liquid column and on density (rm) of the liquid. Further influences are relatively low and known. For highly precise measurements, correction calculations can be made. Recalibration is not necessary.

Principle of MINISCOPE
MINISCOPE testers are U-tube manometers of a special design. In these devices both legs are "inserted in each other". The filling medium is normal tap water. A hollow body of special steel floats on the surface of the water in the inner leg. The glass scale is attached to the latter, which is read via an eyepiece on the integrated optic system. Pressure changes of as little as 1/1000 mbar (0.000014 psi) can be read by means of a reticule and a micrometer drum, which can be precisely adjusted. In addition, a projection device featuring a ground-glass disc instead of the eyepiece is offered as an optional extra.

MINISCOPE manometers
Ideal for pressure and differential pressures with a resolution of better than 0.002 mbar. The model MIN 20 has a measuring range from 0 to 20 mbar (0.29 psi). The model MIN 20 are designed for extremely low differential pressure that can be measured at static pressures up to 600 mbar (8.5 psi).
The MINISCOPE manometer is reproducible primary standards and do not require recalibration. It is very easy to operate and maintain and feature a total uncertainty of only 0.005 mbar.
Generation of a stable and precise test pressure is made easy by the special and very large actively stressed
pressure surface design inside the MINISCOPE manometer. It is inherently temperature stable due to the large mass.
MINISCOPE manometers are ideal for pharmaceutical and semiconductor industries for calibration of monitoring
sensors in clean-room applications; equipment for standards authorities and for flow measurements using the differential pressure method in air-conditioning and ventilation industries, cement industries and others.
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Ideal for pressure measurements of low differentials at high static pressures. MANOSCOPE manometers are operated by means of water or mercury as confined liquids. The negative leg is made of special pressure-proof glass. This design enables you to adjust the reading device to the meniscus of the confined liquid. Accurate positioning and parallactic-free reading of the vernier is possible by means of the slide design. They feature a range up to 2.1 bar (30 psi) and a resolution better than 0.2 mbar. The uncertainty is typically 0.4 mbar. BAROSCOPE manometers operate in the same way as the MANOSCOPE models. However, these models are used as a high precision absolute pressure gauge in the barometric field. They feature ranges up to 1,100 mbar (15.6 psi) or 2,000 mbar (28.4 psi) with the same specification as for the MANOSCOPE. baroscope-S-H.jpg(4467Bytes)
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Primary Pressure Standards

Ametek Pressure Calibrators