WIKA TR10-L Betriebsanleitung Seite 14

4. Design and function
4.3 Description
The model TR10-L, TR10-0 (resistance thermometer) or TC10-L, TC 10-0 (thermocou-
ple) electrical thermometers are comprised of a measuring insert which is built into a
certified Ex d case. In combination with a flame path that is screwed into the head, the
measuring insert functions as a flameproof joint. The measuring insert is replaceable.
EN
Sensor design in model TR10-L, TR10-0
The measuring resistor is embedded in ceramic powder, heat-resistant potting
compound, cement compound or thermal compound. A one-sided sealed tube, which
is welded to a MIMS cable, forms the external shell of the probe tip of the measuring
insert.
Sensor design in model TC10-L, TC10-0
The measuring insert of the thermocouple is manufactured from MIMS cable. The
thermocouple is formed by the internal leads of the MIMS cable. The weld spot of the
thermocouple is, depending on the design, either ungrounded welded with the external
leads of the MIMS cable or grounded welded.
If the temperature sensor is designed as a grounded thermocouple, the thermocouple
is joined directly to the sheath. Designs with a diameter smaller than 3 mm [0.12 in] and
with grounded thermocouples should be considered as galvanically connected with
ground potential.
Versions (see figures page 13):
Thermometers without a flame path may only be used in combination with a certified
■
WIKA thermowell/protection tube with a minimum wall thickness of 1 mm [0.04 in].
The thermometer is marked with IIC and is suitable for use in zone 1.
After installation of a flame path into the connection head of the thermometer, a
■
thermowell/protection tube is no longer mandatory for certification reasons. In most
cases, however, the use of a thermowell (with a minimum wall thickness of 1 mm
[0.04 in]) is necessary for process engineering reasons. The thermometer is marked
with IIB + H
The design of the thermowell/protection tube can be selected as desired, but the
operational process data (temperature, pressure, density and flow rate) must be
taken into account. If a WIKA thermowell/protection tube is already available or
installed, a flame path is not necessary.
The thermometers models TR10-L, TR10-0 or TC10-L, TC10-0 are manufactured by
WIKA with certified connection heads or connection housings. These housings and
covers are made from aluminium or stainless steel. The cover is optionally available
with a glass window.
→ For possible sensor measuring ranges, see chapter 9 "Specifications".
It must be taken into account that it is not possible to consider all potential usage cases.
14
and is suitable for use in zone 1.
2
WIKA operating instructions, models TR10-L, TC10-L, TR10-0, TC10-0 (Ex d)