Specifications / 4. design and function, Design and function – WIKA TR25 Benutzerhandbuch
Seite 10

14073045.01 10/2013 GB/D
10
WIKA operating instructions model TR25 (Ex i)
GB
Pressure equipment directive
■
For instruments with nominal widths of ≤ DN 25 (1“), an EC conformity evaluation in
accordance with the Pressure Equipment Directive (PED) is not permitted.
■
Instruments with nominal widths of ≤ DN 25 (1“), and thus without CE marking, should be
designed and manufactured in line with the applicable sound engineering practice (PED
article 3, chapter 3).
■
For instruments > DN 25 (1“) and for the associated marking on the measuring instrument
or thermowell, WIKA confirms conformity with the 97/23/EC Pressure Equipment Directive in
accordance with the conformity assessment procedure, module H.
For further specifications see WIKA data sheet TE 60.25 and the order documentation.
4. Design and function
4.1 Description
This resistance thermometer, through a wide variety of process connections, enables trouble-free
connection to many different processes.
3- or 4-wire platinum measurement resistances in accuracy classes A and B per DIN EN 60751
serve as sensors.
Analogue or digital transmitters built into the connection head are capable of making various
output signals available, for example 4 ... 20 mA, HART
®
protocol, FOUNDATION™ fieldbus or
PROFIBUS
®
PA.
3. Specifications / 4. Design and function