First Sensor launched high-precision 2-in-1 Differential Pressure Sensors

  • Differential pressure sensors based on the thermal measurement of microflows record pressure ranges from 0 to ±5,000 Pa

First Sensor has launched its new LHD ULTRA series of pressure sensors, with all sensor types now available as samples – the first of which have already been delivered to customers. The high-precision 2-in-1 differential pressure sensors combine two sensing elements with different pressure ranges in a single housing.

The models in the series feature a 16-bit analog digital converter for the upper and lower pressure ranges. A special signal processing routine delivers 24-bit resolution for the entire pressure range. Not only do they offer a high resolution, but they also boast compact dimensions and a broad spectrum of applications.

The dual application of the thermal-based MEMS elements and the adapted installation and connection technology (SDCT) means that the LHD ULTRA models are extremely compact with a height of just 7.4 millimeters, and their vertical pressure connections make them ideal for manifold mounting.

The LHD ULTRA series is based on the thermal measurement of microflows and benefits from a piece of First Sensor’s own key technology, which involves integrating the microflow channel and thermal MEMS sensing element on a silicon chip.

The recently launched series offers exceptional dynamics with a maximum pressure range of up to 5,000 Pa. Further benefits of the LHD ULTRA series from First Sensor include extremely high flow impedance in combination with low flow leakage and the resulting high resistance to dust and moisture. Even in applications where long hose connections cannot be avoided, the sensor response and accuracy remain unaffected. The LHD ULTRA series excels in flow measurement applications, where a high degree of accuracy is needed at low differential pressure measurements. Each device comes standard with an onboard barometer for optional real-time common-mode pressure compensation. This means that the customer can choose between mass or volumetric flow measurement without the need for an external ambient pressure reference device. An optional small form-factor FFT connector and ribbon cable allows for easy bypass measurement in the final assembly.

The series also offers excellent long-term and offset stability thanks to patented real-time offset compensation and linearizing technology with a standard of quality that outstrips the products currently on the market. Maximum precision comes as standard. The overall accuracy is (typically) 1.5% of the measured value over the entire range from 1% to 100% of the full scale value. The offset reproducibility is ±0.02 Pa per year.

Each LHD ULTRA series model is equipped with a linearized, digital I²C or SPI output, an integrated on-chip temperature sensor and a barometric sensor. 

Thanks to the new LHD ULTRA series from First Sensor, users will never again have to decide whether they want to conduct high-precision measurements in the lower or upper ranges of their pressure applications. Only one option has been possible until now, with nothing available on the market for customers who were looking for both. Now there is finally a solution that bridges all the gaps. The LHD ULTRA series offers a total of three pressure ranges to choose from: 1,250 Pa, 2,500 Pa and 5,000 Pa. All models are available as both unidirectional and bidirectional versions.

The key features of the LHD ULTRA differential pressure sensors:

  • High dynamic range for pressures up to 5,000 Pa (more than a factor of 50 compared with the standard L series)
  • Resolution at low pressure less than 0.02 Pa
  • Outstanding resistance to dusty or damp air
  • Ultra-flat design

This gives the new LHD ULTRA series a particularly broad spectrum of applications, ranging from medical technology to HVAC and VAV applications in industrial settings right through to high-precision filter monitoring.