Differential Pressure Transmitters Explained
Differential pressure measurement provides a reliable way to monitor the difference in pressure between two points in an industrial process application. OleumTech Differential Pressure Transmitters deliver accurate, repeatable DP measurement for flow, liquid level, equipment monitoring, and other demanding industrial applications.
What is Differential Pressure Measurement?
Differential pressure is the difference in pressure values between two defined points within a system or process. It is expressed as △P = P₁ − P₂, where P₁ represents the pressure at the first measurement and P₂ the pressure at the second measurement.
In industrial applications, differential pressure can be used to determine flow rate, measure liquid level in pressurized vessels, monitor filter condition, and detect pressure loss across process equipment. A differential pressure transmitter continuously measures the pressure difference and converts it into an output signal that can be monitored by a PLC, RTU, DCS, SCADA system, or other process control equipment.
How Do Differential Pressure Transmitters Work?
A differential pressure (DP) transmitter measures the difference in pressure between two points using separate high-side and low-side process connections. The pressure difference causes an internal sensing diaphragm to deflect, and the transmitter converts this response into a proportional electrical or digital output signal. This signal can be transmitted to a PLC, RTU, or SCADA system for continuous monitoring and control.
By accurately measuring differential pressure, these transmitters can be used to determine flow rate, measure liquid level in pressurized vessels, monitor filter condition, and detect pressure changes across process equipment.
Advantages of DP Transmitters
Differential pressure transmitters provide a versatile and reliable method for measuring and monitoring pressure differences across industrial processes and equipment. Because DP measurement can be applied to flow, liquid level, filtration, and equipment performance, a single measurement principle can support a wide range of process monitoring and control applications.
- Versatile Process Measurement: Differential pressure can be used to measure flow, liquid level, filter condition, and pressure loss across process equipment.
- Accurate, Continuous Monitoring: DP transmitters provide continuous measurement for improved visibility into changing process conditions.
- Liquid and Gas Applications: Differential pressure measurement can be applied across a variety of liquid and gas processes.
- Remote Process Monitoring: Transmitter outputs allow differential pressure data to be monitored remotely through industrial automation and control systems.
- Control System Integration: Multiple output and communication options enable integration with PLCs, RTUs, SCADA systems, and other process control equipment.
- Reliable Industrial Performance: Industrial DP transmitters can be designed for dependable operation in harsh environments and demanding process conditions.
Common Differential Pressure (DP) Measurement Applications
DP Transmitters provide accurate differential pressure measurement across a wide range of process conditions, making them an ideal choice for many common Oil & Gas and Industrial applications.
Differential Pressure Transmitters for Level Measurement
Differential Pressure (DP) Flow Measurement
Differential Pressure Measurement for Heat Exchangers
Featured Products
As a differential pressure transmitter manufacturer, OleumTech provides accurate and reliable DP measurement solutions designed for flow, level, equipment monitoring, and other demanding industrial applications.
HDPTxxxx
Differential Pressure Transmitter
PRODUCT HIGHLIGHTS:
- Pressure type: differential pressure
- Multiple measurement ranges from
-435 to 1500 PSI (-12041 to 41520 inH2O) - Reference accuracy: ± 0.075% of full span
- Stability: ± 0.2 % Upper Range Limit / 5 years
- Output signal options:
(1) 1-5 V (2) RS485 Modbus
(3) 4-20 mA (4) 4-20 mA/HART - TD ratio of up to 100:1 (accuracy not affected at
TD ratio of 10:1 and below)1 - All models support PV reversal (high side / low side)
except for the 1500 PSI model - Backlit LCD provided with both internal
and external control buttons - Diaphragm option: Hastelloy C or 316L SS
- 2X overload pressure using dual diaphragm structure
- HART support:
– Universal and Common Practice Commands supported
– Compatible with most HART Field Communicators - Operating temperature:
-40 to 60 °C (-40 to 140 °F)
LCD: -20 to 60 °C (-4 to 140 °F) - Dual seal certified per CSA C22.2 No. 30-20
- Accurate filling fluid technology eliminates effects of temperature and static pressure
- Process temp. measurement tag supported on
Modbus and HART, -40 to 85 °C (-40 to 185 °F)2 - Explosion-proof (standard on all models)
- Intrinsically Safe (4-20 mA/HART options only)
- NACE MR0175 Compliant
- Mounting Kit Available
Differential Pressure Measurement FAQs
What is a differential pressure transmitter?
A differential pressure transmitter, or DP transmitter, is an instrument that measures the pressure difference between two points. By comparing the high-pressure and low-pressure sides of the sensor, it provides an accurate differential pressure measurement for applications including flow measurement, level measurement, filter monitoring, and process control.
How does a differential pressure transmitter work?
A differential pressure transmitter measures the difference between two points using separate high-pressure and low-pressure ports. Pressure is applied to an internal diaphragm, which deflects in proportion to the differential pressure. The transmitter converts the applied pressure readings into a standardized output signal for industrial control systems, allowing operators to accurately monitor flow, liquid level, filter condition, and other critical process variables in real time.
What is differential pressure?
Differential pressure is the difference in pressure between two separate points within a process. It is calculated by subtracting the pressure at one measurement point from the pressure at another (ΔP = P₁ − P₂).
What is differential pressure measurement used for?
Differential pressure measurements provide valuable information about process conditions. DP measurements are commonly used to calculate flow, determine liquid level in pressurized vessels, monitor filter performance, and identify pressure losses across piping and process equipment.
How is differential pressure used to measure flow?
By measuring pressure drop across an engineered restriction from devices such as an orifice plate or venturi tube, differential pressure transmitters can accurately measure flow rates to maintain process conditions needed to optimize production and ensure product quality.
How is differential pressure used to measure level?
DP Level Measurement technology utilizes pressure readings and a fluid’s liquid density, or Specific Gravity (SG), to determine and output its level. By measuring the head pressure (high side) and gas/vapor pressure (low side) difference between two points, DP transmitters can accurately determine liquid level while providing reliable performance in demanding industrial environments.