NOSHOK 756 Series Digital Pressure Transmitters - Manual (Page 4)

2 Product Description
The pressure transmitter can be used in level control as well as pressure measure-
ment in process applications. A variety of process connections, measurement ranges,
electronic interfaces and display options offer a product for a wide range of applica-
tions.
2.1 Construction
The Digitrans consists of a pressure sensor, a control interface unit and a housing
cover with optional display. Different modular configurations are available allowing a
variety of designs.
2.1.1 Pressure Transducer
The pressure transducer has a piezo-resistive or thinfilm measurement cell depend-
ing on the pressure range. The sensors are temperature compensated, and have a
fully welded membrane which is "helium" leak-tested. Pressure transducers do not
have internal seals.
Pressure transducers further distinguish themselves from one another based on their
ranges and the types of media-touching materials. Different versions of process con-
nections can be selected for a wide range of application conditions.
2.1.2 Control Interface Unit
The control interface unit contains the terminal compartment and the keypad used in
programming the device. The four keys must be active (unlocked) before use. The
keypad is locked during normal operation to protect data and functions previously en-
tered. The keypad automatically locks after 10 minutes of disuse. The control inter-
face converts the sensor’s digital signal into a standard 4-20 mA current signal.


  
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