WIKA TR12 Serie Manual De Instrucciones página 16

3. Commissioning, operation
3.6.2 Possible installation methods with the marking
II 1/2G Ex ia IIC T1 ... T6 Ga/Gb or II 1/2D Ex ia IIIC T65 ... T125 °C Da/Db
EN
Zones 0, 1, 2 or
zones 20, 21, 22
Thermowell
TWxx
The probe or thermowell tip protrudes into zone 0. The case or connection head is in zone
1 (zone 21) or zone 2 (zone 22). It is sufficient to use an Ex ib type circuit.
Zone separation is guaranteed if sufficiently sealed (IP66 or IP67) process connections are
used.
Examples of suitable process connections include gas-tight standardised industrial
flanges, threaded connections or pipe connections.
The process connections, thermowells or cases used must be designed such that they
withstand all influencing variables resulting from the process, such as temperature, flow
forces, pressure, corrosion, vibration and impacts.
16
Hazardous area
Zones 1, 2 or
zones 21, 22
Process
connection
Connection head/
Field case
Compression
fitting
WIKA additional information TR12/TC12, intrinsically safe designs (Ex i)
Non-hazardous area
Tx12-B
Tx12-A
Option:
with built-in
transmitter
e.g. T32
Tx12-B
Tx12-A
Associated
electr. equipment
Intrinsically
safe supply or
suitable barrier
Intrinsically
safe supply or
suitable barrier