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OEM wet/wet differential pressure sensor - Model PV9M

OEM differential pressure sensor PV9M

Product description

With a 19 mm (~3/4”) diameter and a 15 mm (~5/8”) length, the PV9M model is the world’s smallest OEM wet/wet differential pressure sensor packaged in a hermetically-sealed, fully-welded 316L stainless steel housing. It has been specifically designed to measure low to medium differential pressures under high line pressures (up to 200 bar). Both pressure diaphragms (low- and high-pressure sides) are made of stainless steel 316L and can be in contact with any compatible liquid or gas, a perfect fit for demanding applications in harsh environments. This low-cost sensor utilizes the latest technologies to provide a highly-accurate and reliable differential pressure measurement.

The sensor integrates a single solid-state, piezoresistive MEMS silicon die which acts as the sensitive element and converts pressure into an electrical signal. Using advanced techniques of MEMS fabrication (like wet etching, anisotropic etching), a thin diaphragm is crafted inside the silicon die. The thickness of the diaphragm is individually adapted to each pressure range so as to get the highest possible sensitivity without breaking under full pressure load.

Thanks to the monocrystalline structure of the silicon, the pressure sensor exhibits no measurable hysteresis and provides an excellent repeatability, making it highly reliable and highly precise over years of operation.

Besides being very cost-efficient and well-suited for mass production, the silicon monolithic structure withstands overpressures to twice the pressure range without damage or effect on the future performance of the sensor and has a life expectancy of tens of millions of cycles. The sensor is also highly sensitive, exhibiting a high signal with a low power excitation, which is ideal for battery-operated systems.

For protection against media and for ease of integration, the silicon die is mounted and wire-bonded on a glass feedthrough (header) and integrated into a high quality, hermetically-sealed, fully-welded 316L stainless steel enclosure. The housing is filled with a silicone oil on both side and closed by two very thin 316L stainless steel diaphragms. The silicone oil and the diaphragms both reliably transmit the pressure to the die while isolating the latter from the media.

Each sensor is individually tested under various harsh environments and conditions as part of our stringent quality procedures. Each sensor must pass all tests in order to be delivered. An individual calibration report can be delivered with the sensor upon request.

Specifications

Physical characteristics
Pressure range 0 to 2 bar through 0 to 20 bar
Safe overpressure 2 x (positive side), 1.5 x (negative side)
Burst pressure 3 x (positive side), 2 x (negative side)
Line pressure 200 bar
Environmental characteristics
Storage temperature -40 to 125°C
Operating temperature extremes -40°C, 125°C
Maximum operating temperature span 140°C
Ambient temperature -40 to 125°C
Electrical characteristics
Power supply / excitation between 0.5 mA and 2 mA (1 mA typ.)
Typical output signal 0 ~ 150 mV
Bridge resistance at 25°C (77F) between 2.5 kΩ and 4.5 kΩ
Mechanical characteristics
Electrical connections leads, wires, connector
Mechanical connections ⌀19mm
Materials available 316L Stainless steel
Seal materials available FKM, EPDM, Silicone, NBR
Performance (depending on temperature compensation range)
Type of compensation uncompensated resistors polynomial
Compensated temperature range - -10 to 80°C -10 to 80°C
Linearity ±0.25%FS ±0.25%FS ±0.25%FS
Hysteresis ±0.005%FS ±0.005%FS ±0.005%FS
Repeatability ±0.005%FS ±0.005%FS ±0.005%FS
Zero offset ±20mV ±2mV ±2mV
Span offset ±0 ±0 ±0
Line pressure drift ±0.01 mV/bar ±0.01 mv/bar ±0.01 mV/bar
Temperature drift of Zero ±0.25%FS/K ±0.01%FS/K ±0.01%FS/K
Temperature drift of Sensitivity ±0.03%/K ±0.03%/K ±0.03%/K
Stability (per annum) ±0.1%FS ±0.1%FS ±0.1%FS

All values are typical values.