sensors for high pressures and high temperatures, up to 150°C — Series 6L HP and 7L HP

Description

The 6L HP and 7L HP series devices are sensors for measuring high pressures. Keller has developed a new laser welding technology that allows a very thin membrane to be welded to the housing. All presented versions still meet the high level of stability and quality for which Keller has become known worldwide.

Each sensor comes with a calibration certificate indicating sensitivity, linearity, zero, temperature error, and compensation resistor parameters, which mainly account for zero drift and temperature zero.

The sensor design allows for a non-welded connection later using an O-ring seal. This protects the membrane from possible stresses and guarantees the pressure and temperature readings obtained during calibration. Each sensor contains a piezoresistive silicon chip mounted on a polished metal surface. This assembly is then welded to the housing and filled with silicone oil. A thin membrane is laser welded on top, making the structure hermetic. The medium pressure acts on the membrane made of stainless steel and is then transmitted through the oil to the silicon measuring chip.

The sensors are thick because, at high pressures, thicker substrates for silicon chips are required to ensure reliability.

Options

• Membrane/housing: Hastelloy C-276, Titanium
• Oil for low temperatures (-55°C). Fluorinated oil. Olive oil
• Built-in temperature sensor Pt1000 (versions PA, PAA, PR)
• Special characteristics: Linearity, overload pressure, low TC (temperature coefficient)
• Special tests
• Built-in compensation PCB (printed circuit board) see specification for series 30 X
• Compensation algorithms and mathematical model