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11041781.04 01/2020 EN/DE
Pressure gauge with reed contact model 851-A, for Ex areas
EN
2. Design and function
2.1 Overview
Example, model PGS23.063 with contact model 851-A
Laminated safety glass
Pressure element
Blow-out case back
PCB of reed switch
Set pointer
Instrument pointer
Electrical connection
Process connection
2.2 Description
These pressure gauges with reed contact are approved for appli-
cations in hazardous areas. WIKA manufactures and qualifies
these instruments following EN 837-1 (pressure gauges) and DIN
16085 (switch contacts) in the safety version “S3”.
Safety version “S3” per EN 837-1
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.
2. Design and function