How to choose the best pressure sensor?

While choosing the pressure sensor for your job, you have to look for some critical parameters that are very important. Based on these parameters you have to choose the available sensors. Of course you have to look through economical angle also. They are as follows -

1. Accuracy - First and foremost parameter is what kind of accuracy you are looking for? Is your pressure very dynamic? Changing very fast? Or is change slow? What is the rate of change? Do you have to continuously monitor the pressure and record the data or you have to measure it periodically? Based on your process you have to decide what kind of accuracy you are looking for. This will decide the type of sensors. Sensors come with 0.5% accuracy to 0.1%, 0.25% and 0.05% accuracy. As the accuracy increases so as the prices.

2. Output- After you decide the accuracy you have to look for kind of output you are looking for. These sensors come with Voltage and Current output.

Sensors with voltage output are generally used where the sensors and measuring instrument or Data Acquisition system are near. These sensors give out put in mV(millivolt-1000th of a volt) range around 0 - 30 or 100 mv. Some sensors have also got internal amplifier that provide output in the range of 0-5V or 0-10V. These kinds of sensors generally use strain gauges. The sensors with inbuilt amplifiers also provide internal zero and span adjustment facility. Though, because of these internal amplifiers, the frequency response decreases.

Sensors with current output are generally used when the distance between sensors and the measuring instrument or Data Acquisition system is more like in big plants. As the output is in current form they have high noise immunity and they also provide zero and span adjustment. They also offer high frequency response.

3. Environment - where your sensors will be located? This criteria is also very important factor in deciding the sensor.  The operating environment will decide the mechanical structure of the sensor. If the sensor is to be used in harsh environment, it will have extra protection and because of these, it will cost more also. While the sensors that is to be used indoors, will cost less.

4. Fitting - This is also important factor. How you are going to fit the sensor where you want to use it. Does the sensor come with easy fitting couplings? Or you have to make a spatial mechanical arrangement for fitting ?
You have to consider all these factors before considering a particular type of pressure sensor which will fit into your design.