What is hydrostatic pressure transmitter?

Hydrostatic Pressure Transmitters is an instrument that measures the hydrostatic pressure or differential pressure exerted by a hydrostatic head.

Feel the measured pressure through the remote transmission device installed on the pipeline or container. The pressure is transmitted to the main body of the transmitter through the filling silicone oil (or other liquid) in the capillary tube. Then there is the delta chamber and the amplifier circuit board in the main body of the transmitter. Convert into 4-20mA DC signal output. HP Smart can communicate with a HART handheld communicator. Use it to set, monitor, or form an on-site monitoring system with the host computer.

Hydrostatic Pressure Transmitters are often used to measure the level, flow, and pressure of liquids, gases, or steam under high working pressure environments.

RFQ

Pressure Transmitters

• Features
• Specifications
• Applications

Features of Hydrostatic Pressure Transmitter

The Hydrostatic pressure transmitter is used to measure the liquid level, flow, and pressure of the liquid, gas or steam under high working pressure, and then convert to 4~20mA DC signal output.

The Hydrostatic pressure transmitter is used to measure the liquid level, flow, and pressure of the liquid, gas or steam under high working pressure, and then convert to 4~20mA DC signal output.

• The high hydrostatic pressure transmitter can measure differential pressure below 32MPa hydrostatic pressure.
• With 32MPa working pressure and overload protection.
• Ensuring reliable application of the transmitter in Hydrostatic pressure systems.

Read more about: Steam pressure transmitter-Pressure measure on steam pipeline 

Specifications of Hydrostatic Pressure Transmitter

Measure Range of Hydrostatic pressure sensor:

Differential pressure: 0-1.3-6790KPa
Hydrostatic pressure: 32MPa

• Use object: liquid, gas or steam
• Output signal: 4-20mA dc. Output superimposed HART protocol digital signal (two-wire system)
• Power source: external power supply 24V dc. Power supply range 12V ~ 45V
• Installation in dangerous places:
  • Flameproof  ExdIIBT5Gb;(explosion-proof certificate no. :CE16.1163)
  • Intrinsically safe ExiaIICT4/T5/T6Ga;（explosion-proof certificate no. : CE15.2354X） ;
• Accuracy: ± 0.1%, ±0.2%
• Stability: ±0.25%/6 months of maximum range

Model	Transmitter type
HP	Absolute pressure transmitter
Code	Scale range
2	0-0.10～3.5kPa(0-10～350mmH2O)
3	0-0.8～8.0kPa(0-80～800mmH2O)
4	0-4.0～40kPa(0-400～4000mmH2O)
5	0-20～200kPa(0-2000～20000mmH2O)
6	0-70～700kPa(0-0.7～7kgf/cm2)
7	0-210～2100kPa(0-2.1～21kgf/cm2)
8	0-700～7000kPa(0-7.0～70kgf/cm2)
9	0-2.1～21MPa(0-21～210kgf/cm2)
0	0-4.1～41MPa(0-41～4100kgf/cm2)
Code	Output form
E	Linear output 4-20mAdc
SF	Linear/square root output 4-20mAdc +HART signal,，Full function buttons on site
F	MODBUS-485 signal
Code	Structural materials
	Flange connector	Exhaust/Drain valve	Isolation diaphragm	Filling liquid
22	316 Stainless steel	316 Stainless steel	316 Stainless steel	Silicone oil
23	316 Stainless steel	316 Stainless steel	Hastelloy C	Silicone oil
24	316 Stainless steel	316 Stainless steel	Monel	Silicone oil
25	316 Stainless steel	316 Stainless steel	Tantalum	Silicone oil
33	Hastelloy C	Hastelloy C	Hastelloy C	Silicone oil
35	Hastelloy C	Hastelloy C	Tantalum	Silicone oil
44	Monel	Monel	Monel	Silicone oil
Code	Shell material	Conduit inlet dimensions
A	Low copper aluminum alloy polyurethane coating	M20×1.5
B	Low copper aluminum alloy polyurethane coating	1/2-14 NPT
C	Stainless steel	M20×1.5
D	Stainless steel	1/2-14 NPT
Code	Pressure connection
L1	1/4NPT-18 Internal thread（excluding waist joint standard）
L2	1/2NPT-14 Internal thread
L3	M20×1.5 External thread
Code	Optional parts
M4	LCD multi-power digital display head
B1	Pipe bending bracket
B2	Plate bending bracket
B3	Pipe mounting bracket
C02	M20×1.5 nut and Φ 14 pressure short tube
C12	1/2NPT-14 external thread and Φ14 pressure short tube
C22	1/4NPT-18 external thread and Φ14 pressure short tube
C32	1/4NPT-18 to M20×1.5 external thread
C42	1/2NPT-14 to M20×1.5 external thread
C43	1/2NPT-14 to 1/4NPT-18 internal thread
C44	1/2NPT-14 to 1/2NPT-14 external thread
C45	1/2NPT-14 to G1/2 external thread
D1	The side discharge valve is on the upper part
D2	The side discharge valve is on the upper part
X1	Oil ban
Da	Flameproof ExdIIBT5Gb;(explosion-proof certificate no. : CE16.1163)
Fa	Intrinsically safe ExiaIICT4/T5/T6Ga;(explosion-proof certificate no. : CE15.2354X)

Hydrostatic Pressure Transmitter Applications

• Viscous medium at high temperature
• Crystallizable medium
• Precipitating medium with solid particles or suspended matter
• Strong corrosive or highly toxic medium
• It can eliminate the phenomenon that the pressure guiding tube leaks and pollutes the surrounding environment. It can avoid the instability of the measurement signal when the isolation fluid is used. The tedious work of frequently supplementing the isolation fluid is required.
• Continuous and accurate measurement of interface and density
• The remote transmission device can avoid the mixing of different instantaneous media. So that the measurement result truly reflects the actual situation of the process change.
• Occasions requiring high hygiene and cleanliness
• For example, in the production of food, beverage and pharmaceutical industries, it is not only required that the parts of the transmitter contacting the medium meet the hygienic standards. It should also be easy to wash. To prevent cross-contamination of different batches of media.

Extended reading: Silicon Pressure Sensor

Hydrostatic Pressure

Hydrostatic pressure is the pressure generated by the weight of the liquid above the measurement point when the liquid is stationary. The height of the liquid column with uniform density is proportional to the hydrostatic pressure. As the weight of the fluid exerting downward force from above increases, the hydrostatic pressure increases in proportion to the depth measured from the surface.

Read more about: Differences! Static pressure vs dynamic pressure vs total pressure

If the fluid is inside the container, the depth of the object placed in the fluid can be measured.
The hydrostatic characteristics of a liquid are not constant, and the main factors affecting it are the density and local gravity of the liquid. In order to determine the hydrostatic pressure of a particular liquid, both quantities need to be known.

The deeper an object is placed in a fluid, the greater the pressure it bears. This is because the weight of the fluid is higher than its weight. Due to the weight of the fluid, the denser the fluid above it, the greater the pressure on the submerged object.

Measuring principle

The pressure in the liquid increases as the filling height increases. The hydrostatic pressure is transmitted to the measuring unit through the stainless steel diaphragm. Bubbling, accumulation of liquids, fluctuating electrical characteristics, and container design will not affect the measured value.

Extended reading: What is flush diaphragm?

Formula for calculating hydrostatic pressure

The formula for calculating the hydrostatic pressure of a column of liquid is:

The above calculation formula is also the working principle of hydrostatic liquid level sensor.

What is a Hydrostatic pressure sensor?

The hydrostatic pressure sensor measures the hydrostatic pressure applied by the hydrostatic head. Output 4-20mA.
Use a hydrostatic pressure transmitter to measure the storage tank and pump inlet. And other applications where hydrostatic pressure is used to determine the liquid level.

Hydrostatic Pressure Sensor/Transmitter can also be used with paperless recorder.

What is a hydrostatic level sensor?

Hydrostatic Level Sensor measures the hydrostatic pressure by the submersible pressure sensor. The static pressure of the liquid is proportional to the height of the liquid. Then the static pressure was converted into an electrical signal. Convert to analog signal output or 4-20mADC. With digital display. For water level measurement, hydrostatic level sensor is a low cost type. Different types of measuring cells are used in level measurement based on the hydrostatic principle.

Lightning protection, anti-corrosion, explosion-proof optional. IP68 is optional.

Read more about: Hydrostatic Level Sensor

How does a hydrostatic level transmitter work?

The basic working principle of Hydrostatic Level Sensor is static pressure level measurement.

In liquid, the pressure generated at a certain depth is generated by the weight of the medium itself above the measurement point. It is proportional to the density of the medium and the local acceleration of gravity.

The formula P = ρgh reflects the proportional relationship between them.

Where P = pressure, ρ = medium density, g = gravity acceleration, h = depth of measurement point.

Therefore, the physical quantity measured by the input liquid level gauge is actually pressure. It can be understood by the calibration unit mH2O of the input level gauge. The actual liquid level must be obtained by conversion after knowing the two parameters of density and gravity acceleration. In the industrial field, such conversion is usually performed by a secondary instrument or PLC.

The Hydrostatic Level Sensor mainly measures corrosive liquids such as hydrochloric acid, hydrogen peroxide, etc. Or chemical and electroplating wastewater. Mainly used in measuring corrosive media. It has the advantages of strong corrosion resistance and stable performance.

Extended reading: Static pressure vs dynamic pressure vs total pressure

Hydrostatic Pressure Sensors for liquid level measurement

There are various methods and techniques for measuring fluid level using hydrostatic pressure sensors. Depending on the installation, they all have advantages and disadvantages. Hydrostatic pressure measurement is an accurate and convenient technique for determining fluid height or volume.

Let’s take a look at each according to the installation location of the hydrostatic pressure sensor.

Externally mounted type

The Hydrostatic pressure liquid level sensor can be installed to the outside of the container through threads or flange fittings. If necessary, capillaries can also be used.

Submersible type

If the externally mounted sensor is not available, a submersible pressure sensor can be used. The electrical connection with IP68 rating is suitable for long-term permanent immersion. The electronic equipment of the sensor can be protected from the external environment.

Read more about: [What is and How it Works]Hydrostatic Level Sensor

What does a differential pressure sensor do?

DP transmitters are Differential Pressure Transmitters. DP transmitter measures the pressure difference between the gas or liquid at both ends of the transmitter. Output 4~20mA, 0~5V. Used for liquid level, density, and pressure of liquid, gas, and steam.

DP transmitters are different from pressure transmitters as they have 2 pressure interfaces. With flanges, capillaries, valves, brackets, throttle devices. Differential pressure transmitters are used to measure the level, density, and flow of liquids, gases, and vapors. Then convert it into 4–20mADC current signal output.

Read more.

What is pressure transmitter how it works?

A pressure transducer often called a pressure transmitter, is a transducer that converts pressure into an analog electrical signal.

Although there are various types of pressure transducers, one of the most common is the strain-gage base transducer.

The conversion of pressure into an electrical signal is achieved by the physical deformation of strain gauges, which are bonded into the diaphragm of the pressure transducer, and wired into a Wheatstone bridge configuration.

Pressure applied to the pressure transducer produces a deflection of the diaphragm, which introduces strain to the gages.

The strain will produce an electrical resistance change proportional to the pressure.

Read more.

Hydrostatic pressure transmitter fault debugging steps:

Related Blogs

Extended reading: Use of high temperature melt pressure sensor

Hydrostatic pressure transmitter/sensor measures the level, density, and pressure of liquid, gas, or steam. And then converts it into a 4-20 mA DC signal output. The Hydrostatic pressure transmitter can communicate with the HART communicator intelligently. Use it to set, monitor or form a site monitoring system with the host computer. Use a Hydrostatic pressure sensor to measure tanks, processing vessels, headers, pump inlets and others using hydrostatic pressure to determine the liquid height. SI3051HP Hydrostatic pressure transmitters, with working Hydrostatic pressure up to 32Mpa.

Extended reading: Best Price Ceramic Pressure Sensor

Sino-Inst offers a variety of Hydrostatic Pressure Transmitters for industrial pressure measurement. If you have any questions, please contact our sales engineers.

Request a Quote

KimGuo11

Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.

Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.

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Absolute pressure transmitters measure the absolute pressure of the medium in the equipment. Its reference pressure is the absolute value 0 (vacuum), which has nothing to do with atmospheric pressure. Therefore, there is a vacuum sealed chamber on the low-pressure side of the pressure core.

When the fluctuation amplitude of the actual atmospheric pressure affects the process parameters beyond the allowable range, the use of absolute pressure transmitters is necessary. For example, in places where the local average atmospheric pressure deviates greatly from the standard atmospheric pressure.

Absolute Pressure Transmitter Features

• Sensor Type : Industrial Pressure Transducers
• Full function buttons on site
• Pressure ranges: 0 … 1 mbar up to 0 … 600 bar
• Output/Span : 0 – 10 V, 0 – 5 V, 1 – 5 V, 10 mV/V, 4 – 20 mA, HART
• Pressure Port/Fitting : 1/2 MNPT, 1/4 FNPT, 1/4 MNPT, 1/8 MNPT
• Operating Temperature Range: -40 – 85 °C [ -40 – 185 °F ]

Extended reading: How to calibrate HART pressure transmitters

Specifications

Order Guide

Read more about: Common Units Of Pressure

What is the absolute pressure? 

The pressure expressed with complete vacuum as the zero standard is called absolute pressure. Absolute pressure has only positive values.

What is absolute pressure transmitter?

Absolute pressure (AP) transmitter measure relative to perfect (full) vacuum pressure (absolute zero pressure).

Therefore, AP transmitters are not affected by fluctuations in the local atmosphere.

All absolute pressure measurements are positive. The letter ‘a’ or the abbreviation ‘abs’ in the unit of measure (i.e., inH₂O(abs) or psia) indicates an absolute pressure measurement.

Any critical storage and delivery (toxic gases) will change due to atmospheric conditions. So these systems must be accurate and use static references.

Absolute pressure transmitters are used in applications where the pressure of a gas or liquid is isolated from changes in atmosphere. For example, when testing a sealed pressure vessel for leaks for a long time.

How do absolute pressure sensors work?

The absolute pressure transmitter is mainly composed of two parts. One part is directly connected to the side to be measured. The other side is designed as an absolute vacuum reference chamber. This makes the two compartments form Absolute pressure. When the pressure on both sides is inconsistent, the difference signal will be transmitted through a special transmission line. The computer system in the background can calculate the difference. The pressure value on the measured side is directly displayed.

Applications for Absolute Pressure Sensors

• Absolute pressure sensors and absolute pressure gauges are often used for industrial high-performance vacuum pumps that need to be monitored.
• It is used to vacuum pack medical products in a clean environment. To ensure hygienic and sterile delivery to hospitals and doctors.
• In the food industry, vacuum packaging can be used when the highest possible vacuum is required to prevent oxygen from deteriorating perishable foods. This greatly extends the flavor and shelf life of the product.
• In meat packaging, a vacuum that meets the requirements must be generated. This can safely guarantee the longest shelf life.
• And pressure sensors affected by the atmosphere cannot monitor the high end of the vacuum.
• Applications that require true absolute pressure sensors and instruments can also be found in scientific laboratories, universities, military and aerospace industries.

Sino-Inst supplies Direct Mount Pressure / Absolute Pressure Transmitter.

Absolute pressure transmitter calibration

1. First make a 4-20mA fine adjustment. It is used to calibrate the D / A converter inside the transmitter. Because it does not involve sensing components, no external pressure signal source is required.
2. Do a full fine-tuning again. Make the 4-20mA, digital reading coincide with the actual applied pressure signal. Therefore, a pressure signal source is required.
3. Finally, re-quantify the range. By adjusting the analog output 4-20mA and the external pressure signal source. Its function is exactly the same as the zero (Z) and range (R) switches on the transmitter shell.

Read more about: Absolute Pressure Vs Gauge Pressure Measuring Instruments

Absolute pressure transmitter VS Gauge pressure transmitter

More Featured Pressure Transmitters and Pressure Measurement Solutions

Sino-Inst is Chinese manufacturer of absolute pressure transmitters. SMT3151AP absolute pressure transmitters, are our main products, which are widely used in USA, South Africa, and other countries.

Contact us any time, if you need the quotation or technical support.

Request a Quote

KimGuo11

Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.

Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.

drurylandetheatre.com

High Temperature Pressure Transducer is specially used for high temperature medium pressure measurement. Such as high temperature liquid, gas, steam, etc. The highest temperature is customized to 850℃.

High temperature resistant pressure sensor is selected as the signal measurement element. The transmitter structure includes a heat dissipation structure, and the high-precision signal processing circuit is located in the stainless steel housing. The sensor output signal is converted into a standard output signal, such as 4-20mA.

Features of SI-2088 High Temperature Pressure Transducer

• Working temperature –55 …850 ° C, customizable;
• Pressure range can also be customized, such as 150MPa high pressure;
• The sensor and pressure interface are fully welded structures, and the housing protection level is IP65;
• The material in contact with the medium is stainless steel, which has good corrosion resistance;
• It is suitable for pressure measurement of high temperature, low temperature and normal temperature media, and can work stably for a long time;
• It is impact-resistant, vibration-resistant and corrosion-resistant;

High temperature pressure transducer for measuring lowest pressure fluctuations in a harsh environment up to 850 ° C. For applications in hazardous areas, the sensor is available with intrinsically safe Ex-ia and non-incendive Ex-nA certifications.

Specifications of High Temperature Transducer

Extended reading: High accuracy pressure transducers

Applications of high-temperature transmitters

SI2088 High Temperature Pressure Transducer used in the fields of steam, oil, boiler and heat energy exchange. Realize the measurement of liquid, gas and vapor pressure.

Application examples:

• Industrial field process pressure detection;
• Laboratory pressure calibration system;
• Navigation and Shipbuilding;
• Aviation and aircraft manufacturing;
• Air separation equipment and thermal power unit;

Extended reading: Common Pressure Sensor Applications

Application of high temperature pressure transmitter in steam pipeline

Pure steam pipes have good mechanical properties and thermal insulation properties. Under normal circumstances, it can withstand a high temperature of 120 ° C. It can withstand a high temperature of 180 ° C by modification or in combination with other thermal insulation materials.

It is suitable for thermal insulation of various cold and hot water high and low temperature pipelines. The pressure detection in the steam pipeline is very important. And because of the high temperature characteristics in the pipeline. Therefore, it is suitable to use the high temperature pressure transmitter designed by our company for such occasions.

Extended Reading: MEMS Pressure Sensors

In addition, in the steam system, water hammer (Water Hammer) is one of the main hazards causing casualties. Thereby eliminating the hazard of water hammer. This shows that daily pressure monitoring of the pipeline is very important.

Extended reading: High Temperature Flow Meter

Precautions for the correct use of steam pressure transmitters

   1. Prevent the steam pressure transmitter from contacting with corrosive or overheated media;
   2. Prevent dross from depositing in the conduit;
   3. When measuring gas pressure, the pressure port should be opened at the top of the pipeline, and the pressure transmitter should also be installed at the top of the pipeline, so that the accumulated liquid can be easily injected into the process pipeline;
   4. The pressure guiding pipe should be installed in a place with small temperature fluctuation;
   5. When measuring steam or other high-temperature media, a condenser such as a buffer tube (coil) should be connected, and the working temperature of the transmitter should not exceed the limit;
   6. When freezing occurs in winter, the transmitter installed outdoors must take anti-freezing measures to avoid the expansion of the liquid in the pressure port due to the frozen volume, resulting in the loss of the sensor;
   7. When wiring, pass the cable through the waterproof connector or the flexible tube and tighten the sealing nut to prevent the rainwater etc. from leaking into the transmitter housing through the cable.

High Temperature Pressure Transducers vs. Cooling Elements

Generally, the design method is to reduce the temperature near the pressure transmitter by incorporating mechanical cooling components to dissipate heat.

The cooling assembly may be filled with oil and isolated from the process medium by the isolation diaphragm.

Alternatively, the cooling assembly may include a hollow tube. The shape of the hollow tube is designed to increase heat transfer. This allows the process medium that is allowed to pass to be lowered to a much lower temperature.

The cooling element usually relies on the principle of convection heat transfer. This convective heat transfer principle is a mechanism for transferring heat due to the movement of fluid. In contrast, conductive heat transfer is the transfer of energy due to molecular vibration. In addition to cooling elements, convection is also used in many other engineering practices.

The cooling element may be able to reduce the temperature of the medium. This is usually a much cheaper solution than high temperature sensors. It is assumed that the medium density is not greatly affected by temperature changes within the normal operating range. Then this method can keep the pressure unchanged.

The cooling element usually works in air and water, but it is not suitable for oily media such as hydraulic oil. High temperature sensors must be used in these applications because the viscosity of this medium is highly temperature dependent.

The cooling element should be made of stainless steel so that most process media have maximum corrosion resistance. The nickel content of the steel is usually 1.25% and the chromium content is 0.65% to 0.8%.

The cooling element should withstand a maximum pressure of 5,000 psi at 38 ° C (100.4 ° F) and a maximum pressure of 3500 psi at 400 ° C (752 ° F). It also reduces the liquid process temperature at the sensing element from 260 to 38 ° C (500 to 100.4 ° F).

600 ℃ High Temperature Remote Pressure transmitter / Differential Pressure Transmitter

600 ℃ ultra-high temperature remote transmission pressure transmitter / remote transmission differential pressure transmitter cleverly uses the combination of ultra-high temperature silicone oil and internal isolation diaphragm. This makes the field application temperature greatly increased to about 600 ℃.

Greatly expanded the application range of ultra-high temperature pressure / differential pressure measurement. It can be widely used in coal chemical industry and CSP industry.

How to Select a Pressure Transducer For High Temperature Medium

Define your high temperature pressure transmitter requirements using this checklist:

• Process temperature?
• Cooling mechanism?
• Ambient temperature?
• Pressure range?
• Output signal? 4-20mA
• Electrical connection?
• Process connection?
• Process media type?

More Featured Pressure Transducers and Solutions

SI-702S Ultra-High Pressure Senors

• How to Calibrate a Pressure Transmitter
• Differential Pressure Transmitter Installation Guide
• Use Differential Pressure Transmitter to Measure Liquid Level
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• Differential Pressure Flow Meters
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• SMART HART Pressure Transmitter

Sino-Inst produces and supplies pressure transmitters that meet various extreme temperature conditions. In addition to customizing high temperature pressure transmitters, we can also customize ultra-low temperature pressure transmitters, ultra-high pressure pressure transmitters, etc.

Our high temperature pressure transmitters are suitable for high temperature applications such as steam, food processing and engine monitoring. We widely serve users in various countries and industries.

If you have a special request, you can just contact us for Technical Support.

Request a Quote

KimGuo11

Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects.

Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.

drurylandetheatre.com