6. Commissioning, operation
6.2 Cable connections
The cable gland must be optimally sealed, to ensure that the required protection class is reached.
Requirements for meeting ingress protection
Only use cable glands within their indicated clamping range (cable diameter suitable for the
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cable gland)
Do not use the lower clamping area with very soft cable types
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Only use circular cross-section cables (if necessary, slightly oval in cross-section)
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Do not twist the cable
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Repeated opening/closing is possible; however only if necessary, as it might have a detrimental
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effect on the protection class
For cable with a pronounced cold-flow behaviour the screw connection must be fully tightened
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CAUTION!
The protection class is not valid with armoured cables (stainless steel sheathed)
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Seal should be checked for signs of brittleness and, if necessary, replaced
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6.3 Parallel threads
If the thermometer connecting head, extension neck, thermowell or process connection are
connected to parallel threads (e.g. G ½, M20 x 1.5 ...), these threads must be secured using seals
which prevent liquids from penetrating into the thermometer.
As standard, WIKA uses copper profile seals for the connection between the neck tube and the
thermowell, and flat paper seals for the connection of the connection head and the extension neck
or thermowell.
If the thermometer and the thermowell are already connected, the seals will already be mounted.
The plant operator must check whether the seals are suitable for the operating conditions and
must replace them, if necessary, with suitable seals.
For thermometers without a thermowell, and/or where these are delivered separately, the seals
are not included and must be ordered separately.
Tighten the threads by hand when carrying out the final assembly on the plant. This will
correspond to the delivery status of the premounted components. The final tightening torque
should be applied using a spanner (half rotation).
The seals must be replaced after dismantling!
The seals can be ordered from WIKA, indicating the WIKA order number and/or the
designation (see table).
WIKA operating instructions resistance thermometers, thermocouples
EN
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