SMT3151 TGP -stainless steel sensor process, oil and gas industry_meitu_1

The Gauge Pressure Transmitter SMT3151 TGP,
has been specially designed for the process industry,
and measures vacuum, gauge and absolute pressure ranges of gases, steam, fluids, and dust up to 600 bar.

Sino-Instrument gauge pressure solutions include the traditional mount, and in-line mount transmitters,
all featuring DPharp technology to deliver accurate, repeatable,
and fast-responding gauge pressure measurements.

gauge pressure transmitter

Precision Pressure Transmitter for the Process Industry with HART®-Communication and SIL2 (optionally)

Different process connections,
such as threads and flanges with an internal or flush welded diaphragm,
are available and can be combined with a cooling element,
for media temperatures up to 300°C.
The transmitter is as a standard equipped with HART®-communication;
the customer can choose between a two chamber aluminum die-cast case or a stainless field housing.

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Features of Gauge Pressure Transmitter

  • Nominal pressure: from 0 … 400 mbar up to 0 … 600 bar
  • Output signals : 2-wire: 4 … 20 mA ; others on request
  • Special Characteristics:
    • turn-down 1:10
    • two chamber aluminum die-cast case or stainless field housing
    • internal or flush welded diaphragm
    • HART®-communication
    • IS-version: Ex ia = intrinsically safe for gases and dusts
    • accuracy: 0,1 % FSO
  • Optional versions
    • IS-version: Ex d = flameproof enclosure
    • SIL2 – version according to IEC 61508 / IEC 61511
    • integrated display and operating module
    • special materials as Hastelloy® and Tantalum
    • cooling element for media temperatures up to 300 °C

Common Industrial Applications of Gauge Pressure Transmitter

  • mechanical and plant engineering
  • chemical industry
  • medical technology
  •  food and beverage
  •  oil and gas industry
  •  packaging and paper industry
  • pharmaceutical industry

Flush membrane pressure connection interface

What is a Gauge Pressure Transmitter?

A gauge pressure (GP) transmitter,
compares a process pressure against local ambient air pressure.

Gauge pressure transmitters have ports to sample the ambient air pressure in real-time.

Today’s highly accurate gauge pressure transmitters
can be affected by fluctuations in the local ambient pressure.
Measurements above the ambient air pressure are represented,
as a positive number,
while a negative number represents measurements below ambient.

A gauge pressure measurement is indicated by the letter ‘g’ following the unit of measure of the reading (i.e., inH₂O(g) or psig).

Difference between absolute, gage and differential pressure

Comparison of absolute, gage and differential pressure
Comparison of absolute, gage and differential pressure

Absolute pressure

Absolute pressure is referred to as the vacuum of free space (zero pressure).
In practice, absolute piezoresistive pressure sensors,
measure the pressure relative to a high vacuum reference,
sealed behind its sensing diaphragm.
The vacuum has to be negligible compared to the pressure to be measured.
Sino-Instrument’s absolute pressure sensors,
offer ranges from 1 bar or even 700 mbar as well as barometric pressure ranges.

Gage pressure

Gage pressure is measured relative to the ambient atmospheric pressure.
The average atmospheric pressure at sea level is 1013.25 mbar.
Changes of the atmospheric pressure,
due to weather conditions,
or altitude directly influences the output of a gauge pressure sensor.

A gauge pressure higher than ambient pressure is referred to as positive pressure.
If the measured pressure is below atmospheric pressure,
it is called negative or vacuum gage pressure.
In general, a vacuum is a volume of space that is essentially empty of matter.

According to its quality vacuum is divided into different ranges such as an e.g. low, high and ultra high vacuum.

Differential pressure

Differential pressure is the difference between any two process pressures p1 and p2.
So, differential pressure sensors must offer two separate pressure ports,
with a tube or threaded connections.
Sino-Instrument’s amplified pressure sensors,
are able to measure positive and negative pressure differences,
i.e. p1>p2 and p1<p2.


These sensors are called bidirectional differential pressure sensors,
with ranges of e.g. -1…+1 bar or -2.5…+2.5 mbar.
In contrast, unidirectional differential pressure sensors,
only operate in the positive range (p1>p2)
e.g. from 0…1 bar or 0…2.5 mbar,
and the higher pressure has to be applied to the pressure port defined as “high pressure”.

More Featured Pressure Transmitters:

SMT3151DP smart differential pressure transmitter

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