Pressure Transducers: Protection from Water Hammering and Over Pressure Damage.

Pressure Transducers: Protection from Water Hammering and Over Pressure Damage.
24 March 2023

In many fluid pressure measurement applications, a pressure transducer (or transmitter or sensor) can inadvertently be exposed to overpressure. This is a pressure range greater than what their design is intended for and can often lead to damage, or worse cases, destroy the pressure transmitter.


In addition to overpressure damage, pressure transmitters can be subjected to harm from water hammering. This occurs when short, sharp bursts or impulses of water can affect the pressure transmitter from sudden changes in flow rate. Alternatively, impulses can be experienced in the fluid of hydraulic ram’s banging against a solid surface. The adoption of an impulse-dampening device, also known as a snubber, can aid in protecting your pressure transmitter against this.


Understanding your pressure transmitter's range of tolerance is key to preventing unnecessary damage. For instance, ESI Technology’s flagship pressure transmitter, the GS4200 series has a standard Over Pressure rating of 2x the rate pressure for ranges (-1 to 600bar), this is less for 1000 bar range (1.5x) and for the 1500bar pressure transmitter, the maximum overpressure is 1.1 x 1500bar.

The ESI GS4200 Pressure Transducer. A small device to measure pressure of tanks.
The ESI GS4200


ESI Technology has three feature options that can be added to standard pressure transmitters as a special request. These standard order code extensions include:

  • HO – High Over Pressure: 
    • For instance, a GS4200-0001AB-HO Is a 1bar range transmitter but will use a 4-bar sensor internally (but scaled as a 1 bar) to give a higher overpressure instead of usually a 1-bar sensor scaled as a 1 bar. The usual over-pressure rating for (-1 to 600 bar) sensors is 2 x rated over-pressure.
    • Eg. the maximum Over Pressure for the standard GS4200 would be 2 bar max, but for the extended range sensor, this would be 8 bar with the HO option.


  • SNUB – Snubber
    • Especially for short impulses of pressure.
    • Eg. part number GS4200-0001AB-SNUB would use a 1bar sensor with a snubber built inside the process port. This is an extra piece of hardware.


  • HOS – High Over Pressure with Snubber
    • For extreme cases, a GS4200-0001AB-HOS would use both a higher-pressure sensor internally and a snubber!


Please note, these added feature options have a longer lead time as they are manufactured to order in the United Kingdom, and they will attract an added cost which may vary depending on the sensor design being used.

If you are interested in exploring any of these options for your pressure transmitter, speak with our ADM Instrument Engineering Team today!