Pressure Sensors: Melt Pressure Transducer

A sensor is any device that produces a measurement of a physical value by transforming this value into a signal output that a user can be observed, or one displayed instrumentation.

Pressure Sensors are utilized for numerous applications to help operators control and monitor the stability of various processes while preserving equipment safety.

Here, the focus is on the melt pressure transducer that is applied in plastic extrusion and injection molding. Calibration of the signal output from the sensor must be performed in line with instrumentation.

This is considered crucial to the reliability and accuracy of the pressure measurement.

Appropriate calibration should be conducted at operating temperature with the transducer at rest (no pressure applied) to recompense the temperature effect to zero. All Dynisco pressure transducers come with a rating of temperature effect on zero, and this rating can differ depending on the selected fill media in the transducer capillary.

The zero-output level of the signal will be impacted by the physical properties of the liquid fill media, and this value must be considered when allocating the range with instrumentation and adjustments made for the necessary compensation.

This adjustment would be akin to setting a TARE on a balance, where the temperature effect is analogous to the package of the product being weighed.

The temperature effect published for the three liquid fill options are as follows: 

  • Hg = 15 psi/ 100°F or 27 psi/100°C 
  • Oil = 36 psi/ 100°F or 65psi/100°C 
  • NaK = 30 psi/ 100°F or 54psi/100°C 

According to these values, it is expected that it will be necessary to configure the instrument to accept the signal input as zero by following calibration procedures at the operating temperature of the process.

Example: Process temperature = 400°F, Hg type sensor displays the signal output of 60 psi @ zero pressure

Therefore, depending on the full-scale pressure range of the transducer, this offset would be in addition to the standard combined error specification; so a 10,000 psi range carrying 0.5% combined error (+/- 50 psi) would actually seem to have an offset of 110 psi or more at any given time.

It is critical to bear in mind that when calibration is being performed, there are no alterations made to the signal output, only confirmation that output is still within a tolerance of the model specifications.

Dynisco instruments have been designed to streamline the calibration process of pressure sensors. With minimal keystrokes, Dynisco’s indicators and controllers can test the high and low limit of the signal output.

This information has been sourced, reviewed and adapted from materials provided by Dynisco.

For more information on this source, please visit Dynisco.


Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Dynisco. (2021, September 07). Pressure Sensors: Melt Pressure Transducer. AZoSensors. Retrieved on May 18, 2024 from

  • MLA

    Dynisco. "Pressure Sensors: Melt Pressure Transducer". AZoSensors. 18 May 2024. <>.

  • Chicago

    Dynisco. "Pressure Sensors: Melt Pressure Transducer". AZoSensors. (accessed May 18, 2024).

  • Harvard

    Dynisco. 2021. Pressure Sensors: Melt Pressure Transducer. AZoSensors, viewed 18 May 2024,

Ask A Question

Do you have a question you'd like to ask regarding this article?

Leave your feedback
Your comment type

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.