Functional PrincipleThe WPC-400 gauge is a combination gauge consisting of a Pirani sensor and a cold cathode sensor. Both sensors are constantly active.
At low pressures, only the signal of the Pirani sensor is used for pressure measurement, at high pressures, only the signal of the cold cathode ion sensor. To determine the output signal in the intermediate range, both signals are used proportionally to the pressure. They are combined in such a way that for the user, they behave as one single measurement system.
The gauge can display the vacuum pressure by a 5-digit LED, or communicate with a standard PC through RS485 or Wireless, as well it outputs an analog signal as a logarithm of the pressure over the whole measurement range.