WIKA TR75 - Manual (Page 11)

11325232.04 01/2014 GB/D/F/E
WIKA operating instructions DiwiTherm ® , model TR75 11
GB
4.1.2 DiwiTherm ® for mounting in a thermowell
Sensor
Material: stainless steel
The sensor is made from vibration-resistant, sheathed cable (MI cable).
The sensor diameter should be approx. 1 mm smaller than the bore diameter of the
thermowell. Gaps of more than 0.5 mm between thermowell and the sensor will have a
negative effect on the heat transfer, and they will result in unfavourable response behaviour
of the thermometer.
When fitting the measuring insert into a thermowell, it is very important to determine the
correct insertion length (= thermowell length for bottom thicknesses of ≤ 5.5 mm). In order to
ensure that the sensor is firmly pressed down onto the bottom of the thermowell, the sensor
must be spring-loaded (spring travel: max 10 mm).
Process connection (standard process connection)
Material: stainless steel
Threaded connection: G ½ B
M14 x 1.5
M18 x 1.5
½ NPT
Union nut: G ½ B
Male nut: G ½ B
Neck tube
Material: stainless steel
Neck tube diameter: 12 mm
Standard neck length: 150 mm
others on request
(minimum neck length: 30 mm)
Sensor lengths
Sensor Ø in mm Standard insertion lengths A (l1) in mm
3 110 140 145 170 200 205 230 245 260 294 305 345 350 395 410 445 545
6 - - - 170 200 205 230 245 260 295 305 345 350 395 410 445 545
8 - - - - 200 205 230 245 260 295 305 345 350 395 410 445 545
Special lengths are possible.
4. Design and function