- PL industrial pressure transmitters
- Technology
Capacitive and strain gauge operating principles explained
Ceramic capacitve technology (PL15)
The most important element of the ceramic capacitive technology is the ceramic (Al2O3) measuring cell. After assembly, the ceramic cell element resembles a plate capacitor with a reference electrode and a measuring electrode placed 0.01 mm apart. The capacitance is inversely proportional to the distance between the electrodes. As pressure is applied, the distance changes by a small value and the capacitance changes proportionately. This signal is then converted into pressure by a microprocessor.
Benefits of the ceramic capacitive measuring cell
- Robust direct sensing measuring technology
- Eliminates possibility of contamination from diaphragm fill fluid
- Internal support construction creates very high pressure ratings
- Ceramic cell is more resistant to abrasion, dents or dings that can create measurement offsets
- Highest overload pressure rating, especially with dynamic pressure peaks
Strain gauge technology (PL54)
The PL54 family uses a strain gauge measuring cell inside a thin film stainless steel diaphragm. Strain gauges are attached to the stainless steel measuring cell. Pressure of the medium on the measuring cell causes deflection of the strain gauges, which creates a change in resistance. Tension (positive strain) increases resistance and compression (negative strain) decreases resistance. The change in resistance is proportional to the pressure applied.
Benefits of strain gauge technology
- Suitable for liquids and gases up to 400 bar (5800 psi)
- High burst strength at high ranges
- Fully welded all stainless steel diaphragm provides excellent chemical compatibilty with most harsh media
Flexible sealing concept (PL15)
The PL15 features a flexible sealing concept for installation into new and existing applications. Find out which concept would be best fit for your application in the “Installation guidelines” section.