EN
14073045.04 03/2019 EN/DE
WIKA operating instructions model TR25 (Ex i)
21
7.4 Mounting examples in hazardous areas
7.4.1 Possible installation methods with the marking II 1G Ex ia IIC T6 Ga or
II 1D Ex ia IIIC T65 °C Da
The sensor together with housing or connection head is located in Zone 0 (Zone 20).
An Ex ia type circuit must be used. Connection heads/cases made of aluminium are not
permitted in zone 0. At this position, WIKA uses connection heads/cases made of stainless
steel.
Zones 0, 1, 2 or Zones 20, 21, 22
Hazardous area
Safe area
Thermowell
Thermowell
welded
TWxx
TWxx
Process
connection
Connection head/
Field housing
Tx10-B
Tx10-C
Tx10-C
Tx10-D
Tx10-H
Tx10-H
Option:
with built-in
transmitter:
e.g. T32
Tx10-A
Process
connection
Compression
fitting
Associated
electrical equipment
Intrinsically
safe supply or
suitable barrier
Intrinsically
safe supply or
suitable barrier
Intrinsically
safe supply or
suitable barrier
Intrinsically
safe supply or
suitable barrier
Tx10-A
Tx10-A
Tx10-A
7. Information on mounting and operation in hazardous areas