Pressure Transducer or Pressure Transmitter? The answer depends on output.

Choosing between these a pressure transmitter and a pressure transducer (both of which fall under the pressure sensor category) comes down to the type of output signal your system requires. Transmitters use current signals like 4–20 mA and transducers typically using voltage signals like 0–5 V.

If you are measuring pressure in industrial or commercial applications, you have likely encountered both terms and wondered which is right for your system. The challenge is that both devices perform similar functions, yet their differences impact performance, installation and reliability.

In this article, you will learn:

• How pressure transmitters and transducers work

• How output signal affects selection

• How to evaluate accuracy, cost and application fit

What do pressure sensors do and where are they used?

Both pressure transducers and pressure transmitters are sensors that measure the pressure of air, gas or liquid and convert it into an electrical signal for monitoring or control. The primary difference between the two is how the signal is communicated to your control system. This is a key factor in determining how each will perform over distance, with signal stability and system compatibility.

They are designed to operate in demanding environments including extreme temperatures, shock and vibration across industries such as HVAC/R, oil and gas, medical equipment and water treatment.

Figure 1: Industries that use pressure sensors

What is a pressure transmitter and when should you use one?

A pressure transmitter, like the Ashcroft® GC51 Pressure Transmitter converts pressure into a 4–20 mA current signal and is best suited for long-distance signal transmission.

Transmitters are commonly used in large-scale processing environments where signal integrity is critical, such as:

• Chemical processing

• Food and beverage manufacturing

• Power generation and distribution

• HVAC/R systems

• Industrial equipment and safety systems

Because current signals are less susceptible to electrical noise and signal loss, transmitters are the preferred choice when signals must travel long distances or operate in electrically noisy environments.

What is a pressure transducer and when should you use one?

A pressure transducer converts pressure into a voltage signal and is typically used in systems with shorter wiring distances. While transducers can provide different output types, the most common is a voltage signal such as 0–5 V, selected based on application requirements.

They are often used in applications that require continuous monitoring and faster response times, including:

• Brake pressure monitoring in off-road vehicles and rail systems

• Oil and fuel pressure measurement

• HVAC pumps and control systems

• Medical equipment measuring liquid or gas pressure

Transducers are typically chosen when the sensor is located close to the control system and long-distance transmission is not required.

How does output signal determine which pressure sensor to choose?

The output signal determines whether a pressure transmitter or transducer is the better fit for your system. If your system requires a current input, a transmitter is the right choice. If it requires a voltage input, a transducer is typically used.

Beyond compatibility, output type also affects:

• Signal stability over distance

• Susceptibility to electrical noise

• Installation complexity

• Overall system reliability

This is why output is often the primary decision factor when selecting between the two technologies.

Figure 2.  Pressure transmitter vs transducer output signals 

How do pressure range, accuracy and cost compare?

Pressure transmitters and transducers offer similar performance ranges, but application requirements determine the best option.

Both types typically measure:

• Pressure ranges from very low (0–0.01 in. H₂O) up to 72,000 psi

• Accuracy from ±0.25% to ±2.00% of span

Understanding accuracy requirements

Accuracy is defined as a percentage of full span and varies by application:

Static accuracy (no temperature effects):

• 1% = low accuracy

• 0.5% = average

• 0.25% = good

• <0.1% = high accuracy

With temperature effects (-5 to 185 °F):

• 5% = low accuracy

• 3% = average

• 1.5% = good

• <1% = high accuracy

What factors impact the cost of a pressure transducer or pressure sensor?

The cost of a pressure sensor depends on several factors, including:

• Accuracy requirements

• Output type

• Environmental protection

• Materials of construction

• Certifications and approvals

• Additional features or customization

Rather than choosing based on price alone, it is important to match the sensor to your performance and application needs.

Which type of pressure sensor should you choose for your application?

You should choose a pressure transmitter or transducer based on your system’s output requirements, installation conditions and performance needs. As a general guideline, start with output then refine your selection.

• Use a pressure transmitter for long-distance signal transmission and noisy environments

• Use a pressure transducer for short-distance applications requiring voltage output

Selecting the right device is part of a broader process that includes evaluating accuracy, environmental conditions and system compatibility. 

Ready to learn more?

You now know that the key difference between a pressure transmitter and a pressure transducer is output signal, but successful selection requires a complete understanding of your application. If you still have questions, take a look at the informative resources below, or contact us to speak to a product expert. 

In the meantime, download our guide to learn the common mistakes OEM and system integrators make when selecting pressure sensors.