Endress+Hauser iTHERM TM401, Техническая информация

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iTHERM TM412
Hauser 15
The minimum immersion length is the length of the insert that is fully immersed in the
calibration bath. For a valid recalibration, the value selected for the length IL* must be at least
the value of the previously defined minimum insertion lengths (IL) of the specific types of
insert. For more detailed values, see the previous tables, values without head transmitter.
If the calibration unit used does not allow the insert to be fully immersed as far as the bottom
edge of the top part of the iTHERM QuickNeck, it might be necessary to add an additional
length (ΔL) to IL*. →  13
Formulas for calculating the IL* when recalibrating onsite with iTHERM QuickNeck
Thermowell version Formula
Protection tube diameter 6.35 mm (¹⁄₄ in)
IL* = U + T + 19.05 mm (0.75 in) Protection tube diameter 9.53 mm (³⁄₈ in)
Protection tube diameter 12.7 mm (¹⁄₂ in)
Insulation resistance Insulation resistance ≥ 100 MΩ at ambient temperature.
Insulation resistance between the terminals and the outer jacket is measured with a minimum
voltage of 100 V DC.
Installation
Orientation
No restrictions. However, self-draining in the process must be guaranteed. If there is an opening to
detect leaks at the process connection, this opening must be at the lowest possible point.
Installation instructions The immersion length of the thermometer can influence the accuracy. If the immersion length is too
small then errors in the measurement are caused by heat conduction via the process connection and
the container wall. If installing into a pipe then the immersion length should ideally be half of the
pipe diameter.
• Installation possibilities: Pipes, tanks or other plant components
• To minimize the error caused by heat conduction, a minimum immersion length is recommended
depending on the type of sensor used and the design of the insert. This immersion depth
corresponds to the minimum insertion length for the calibration. →  13
• ATEX certification: Observe the installation instructions in the Ex documentation! →  39