WIKA TR12 Serie Manual De Instrucciones página 9

3. Commissioning, operation
3.1.1 Variant 1
The thermometer is fitted with a certified enclosure in which the terminal block is fitted.
If the thermometer is marked with II 2G Ex ia IIC T1 ... T6 Gb, then it is designed for use
in zone 1. If the thermometer is marked with II 1/2G Ex ia IIC T1 ... T6 Ga/Gb, then it is
designed for use with a thermowell at the partition to zone 0.
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ATEX/IECEx case or connection head (with connection terminals, without transmitter)
Evaluation of the resistance or the thermoelectric potential between electronics outside of
the hazardous area.
Use in zone 1, marking II 2G Ex ia IIC T1 ... T6 Gb
The case or the connection head is in zone 1 (or zone 2). The sensor is located in zone 1.
Use at the partition to zone 0, marking II 1/2G Ex ia IIC T1 ... T6 Ga/Gb
The case or the connection head is in zone 1 (or zone 2). The sensor is within a thermowell
(min. wall thickness 1 mm) which extends into zone 0 via a process connection.
Powering with Ex ia electric circuit fulfills these conditions. The responsibility rests with the
operator.
The permissible ambient temperatures for third-party products can be seen from the
relevant approvals or data sheets.
A heating in the connection head does not occur with variant 1. However, an impermissible
heat reflux from the process which can exceed the operating temperature of the case or
the temperature class, must be prevented through suitable heat insulation or a suitably
long neck tube.
WIKA additional information TR12/TC12, intrinsically safe designs (Ex i)
EN
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