HITACHI

Construction of capsule of absolute pressure transmitter

Hitachi Absolute Pressure Transmitters adopt an E type sensor and uniquely constructed capsule to ensure durability when an excessive pressure is applied. They realize excellent reliability and long-term stability, thus enjoying a good reputation in various plants.

If an excessive pressure is applied, the sensor unit is pressurized and brought into contact with the mounting base to prevent damage to the sensor unit.

For the absolute pressure transmitter, it is important to make the vacuum reference chamber more stable. In Hitachi Absolute Pressure Transmitters, the semiconductor sensor is coupled with the mounting base at high temperature and under high vacuum by using special techniques. This coupling system allows you to obtain a dry, clean and stable vacuum reference chamber. Accordingly, the vacuum reference chamber is kept in high vacuum at any time to realize stable absolute pressure measurement with a minimum of drift in various plants.