High Accuracy Capacitive Pressure Sensors by ES Systems

ES Systems offers highly accurate capacitive pressure sensors in a variety of packages including a capsule, board level, and transmitter package.

These sensors are ideal for those looking for extremely high accuracy and stability with media compatibility. In this blog post, we are going to share some key differentiating points of these sensors compared to traditional sensors for high demand applications.

Accuracy & Total Error Band: One of the most advantageous features of these pressure sensors from ES Systems is performance.

Before diving into the details, here is a quick refresher on the difference between total error band and accuracy. Total error band (TEB) is a single specification that includes all sources of error in a pressure measurement, and is it a comprehensive measure of a sensor's true accuracy. Accuracy is a component of TEB which comprises pressure non-linearity, pressure hysteresis, noise, and pressure non-repeatibility. In addition to accuracy, other possible errors added into TEB include offset, full-scale span, thermal effect on offset, thermal effect on span and thermal hysteresis.

For the various standard ranges from 10 bar to 350 bar, the full-scale accuracy is ±0.125% FS. Next, the total error band is ±0.25%FS from 10 to 100 bar and ±0.5%FS for 200 & 350 bar ranges. Most pressure sensors vary significantly when the total error band is included, if the total error band figure is even provided. Remember that accuracy and TEB specifications are NOT reported in a uniform way. Hence, it is vital for users to read data sheets and the respective fine print very carefully.

High performance and stability is critical in many medical and HVAC applications.

High overpressure: Overpressure tolerance is typically 100x the pressure range. There are very few manufacturers that can provide this high degree of overpressure.

Media compatibility: The seal type and filling oil allow for users to measure the pressures of gases and liquids including harsh media. O-ring options include FKM, EPDM, DBR, VMQ, HNBR. Standard material at the pressure port is stainless steel 316L with an option for titanium or Hastelloy.

Applications: As you can see from these specifications, applications for these sensors are for those needing precise accuracy. The sensors can be oxygen-cleaned if needed. In addition, vacuum measurement can be offered such as -100 kPa to 0 kPa. Here is a summary of models: