Endress+Hauser iTHERM TM401, Техническая информация

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iTHERM TM412
14 Hauser
Due to restrictions of the bath geometries, minimum immersion lengths must be maintained at high
temperatures in order to be able to perform a calibration with acceptable measurement uncertainty.
The same applies when a temperature head transmitter is used. Due to the heat dissipation,
minimum immersion lengths must be maintained in order to ensure the functionality of the
transmitter –40 to +85 °C (–40 to +185 °F).
Minimum insertion length (IL):
Calibration temperature Minimum immersion length (IL)
–196 °C (–320.8 °F) 120 mm (4.72 in)
1)
+80 to +250 °C (+112 to +482 °F) No minimum immersion length needed
+251 to +550 °C (+483 to +1 022 °F) 300 mm (11.8 in)
+551 to +600 °C (+1 023 to +1 112 °F) 400 mm (15.8 in)
1) with temperature head transmitter min. 150 mm (5.91 in) needed
IL
IL*
Δ
L
A0033648
 2 Insertion lengths for sensor calibration
IL Insertion length for factory calibration or recalibration onsite without the iTHERM QuickNeck extension neck
IL* Insertion length for recalibration onsite with the iTHERM QuickNeck extension neck
ΔL Additional length, depending on the calibration unit, if the insert cannot be fully immersed
• To check the actual accuracy rating of the thermometers installed, a cyclic calibration of the
installed sensor needs to be performed frequently. The insert is normally removed for comparison
with a precise reference thermometer in the calibration bath (see graphic, left part).
A reproducible calibration requires the insert to have a minimum insertion length IL. If the insert
is shorter than this minimum length, this reproducibility cannot be guaranteed.
• The iTHERM QuickNeck enables quick, tool-free removal of the insert for calibration purposes. The
entire upper part of the thermometer is released by turning the terminal head. The insert is
removed from the protection tube and directly immersed into the calibration bath (see graphic,
right part). Make sure that the cable is long enough to be able to reach the mobile calibration bath
with the cable connected. If this is not possible for the calibration, it is advisable to use a
connector. →  28
Advantages of iTHERM QuickNeck:
• Considerable time savings when recalibrating the device (up to 20 minutes per measuring point)
• Wiring mistakes avoided when re-installing
• Minimum plant downtime, thereby saving costs