WIKA TR12-M - Handbuch (Seite 21)

GB
7. Information on mounting ... / 8. Safety-related instructions ...
11419904.02 09/2013 GB/D
WIKA operating instructions models TR12, TC12 (Ex d) 21
■ Mounting within non-metallic enclosures:
All electrically-conductive thermometer components within the hazardous area must be
provided with equipotential bonding.
■ Neither repairs nor structural modifications are permitted, and any would void the
guarantee and the respective certification.
■ The manufacturer shall not be responsible for constructional modifications after delivery
of the instruments.
8. Safety-related instructions for the different variants
8.1 Variant 1:
ATEX/IECEx Ex d housings or connection heads (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 d IIC T1-T6 Gb
The flameproof housing or the connection head is in zone 1 (or zone 2). The sensor is in
zone 1. In the case of a separation of Ex-zones, a thermowell (from corrosion-resistant
steel, min. wall thickness 1 mm) must be used. In this case, no power limitation is needed,
since no failure source can occur from the evaluation electronics.
Use with a thermowell at the partition to zone 0, marking II 1/2G Ex d IIC T1-T6 Ga/Gb
The flameproof housing 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.
The thermometer should therefore be operated with a power-limiting circuit.
P
max
: 2 W
U
max
: 30 V
A power supply with Ex ia circuitry fulfills these conditions, but is not required if the limits
can be achieved through other measures. The responsibility rests with the operator.
Temperature class classification, ambient temperatures
For all WIKA connection heads, the following ambient temperature range applies:
(-50) 1 ) -40 … +80 °C
1) The value in brackets applies only for specific low-temperature designs
The permissible ambient temperatures for third-party products can be seen from the
relevant approvals and/or data sheets.