Your low-pressure transducer is an important part of your HVAC, critical environment, clean room or pharmaceutical application. Strict requirements for safety and sanitation need accurate and reliable pressure measurements. In some installations, the pressure transducer is required to be located at a certain distance away from the pressure source.
But what if the transducer is located far away from the pressure source? What effect can the length of pressure tubing have on your pressure readings?
This article will explain the use of pressure tubing with low-pressure transducers and if the length has any impact on pressure measurements.
Why Use Pressure Tubing?
Pressure tubing connects to the pressure fittings on a transducer so the instrument can be mounted away from the pressure source. You can specify pressure tubing in many different lengths to fit the location of your pressure transducer.
The tubing is commonly used in any low-pressure/differential pressure application, such as HVAC systems or critical environments.
Effects of Tubing Length
The length of tubing will not affect the accuracy of your transducer. The instrument will still measure accurate readings regardless of how far away it is from the pressure source.
However, tubing may impact the response time of the unit. The longer the tubing length, the slower the response time of the transducer. However, the amount of time is often negligible.
The Ashcroft CXLdp or DXLdp both provide a standard response time of 250 milliseconds. A CXLdp or DXLdp unit with 100 feet of tubing length would slow down the response time to around 340 milliseconds.
A tubing length of 500 feet would slow the response time to approximately 700 milliseconds, but this is still faster than 1 second. Depending on your requirements, a response time within one second may not be a concern, and this delay may be negligible.
These response time examples provided are based on clean dry gas process media commonly used in low-pressure/differential pressure applications.
Ashcroft recommends that you confirm the acceptable response time of the transducer prior to specifying the tubing length.
In addition, we recommend that the tubing length be approximately the same for both the high and low ports for DP (Differential Pressure) Transducers. Unequal tubing lengths could create false pressure spikes because the port with the longer tubing may register pressure changes slower than the port with the shorter length tubing.
We don’t like to pressure you, but we have more information.
In conclusion, the longer the tubing length, the slower the response time of your pressure transducer, but it should have no effect on the accuracy of the readings.
Now that you understand more about pressure tubing and the effects it can have on pressure transducers, you can research the solution that’s best for your low-pressure application.
Keeping this information in mind can help ensure that you avoid problems and keep your process running with reliable and accurate pressure measurements.
If you want to learn more about pressure transducers, you can read some of our other articles:
- Choosing a Pressure Transducer for Critical Environments
- How Does Media Temperature Affect Pressure Transducer Performance?
- Product Review: GXLdp Differential Pressure Transducer
- How Accurate Are Your HVAC System’s Pressure Instruments?
Feel free to contact us today to talk to one of our industry experts and get your questions answered.
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