2. Design and function
2. Design and function
2.1 Overview
Example model PGT23.100, version "S3" per EN 837
Pressure element
Movement
Transmitter electronics
Pressure compensating valve
Electrical connection with cable box
Laminated safety glass
Process connection
2.2 Description
For the instruments described, because of their robustness and ease of use, Bourdon tube,
diaphragm, capsule and corrugated steel measuring elements are widely used. Under the
influence of pressure, the pressure elements deform within their elastic limits. A mechanical
movement transfers this deformation into a rotational motion. A magnet on the pointer shaft
rotates proportionally to the instrument pointer as a direct linear function of the process
pressure. The angle sensor contained in the transmitter electronics measures the rotational
motion of the magnet in the range 0 ... 270°. The angle change is registered without any
contact and, thus, wear-free and is converted to an analogue output signal via an amplifier.
The span of the output signal corresponds to the measuring span on the dial.
Safety version "S3" per EN 837
This version is made up of laminated safety glass, a solid baffle wall between measuring
system and dial and a blow-out back. In the event of a failure, the operator is protected at the
front side, as media or components can only be ejected via the back of the case.
Ex version
All instruments, except for the model PGT23.063, are also optionally available in a design for
hazardous areas.
2.3 Scope of delivery
Cross-check scope of delivery with delivery note.
Pressure gauges with output signal, optionally for hazardous areas
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EN