WIKA intelliTHERM TGT70, Руководство по эксплуатации

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12 WIKA operating instructions model TGT70
EN
14047194.03 03/2022 EN/DE/FR/ES
6.2 Ambient conditions
Unless the ingress protection of the thermometer‘s housing is specifically identified
in the order confirmation, the instrument must be protected from humid air and other
aggressive atmospheres.
To ensure the best measuring accuracy possible, the ambient temperature on the
indicator case should be between 0 ... 40 °C. Higher or lower ambient temperatures can
cause indication errors.
6.3 Indicator check
Indicator checks should only be carried out in comparison with a more accurate instru-
ment or, if possible, with a calibrated instrument. The temperature during the check must
remain constant. Fluctuating temperatures can lead to reading errors caused by the
different response times of the sensors.
Before checking the indicators of thermometers without thermowells, a waiting time of at
least 5 minutes with the stem's full length properly inserted is required to allow tempera-
ture equalisation.
Temperature checks using thermometers with sensors assembled with thermowells
can, in many cases, only result in a reference temperature at the instrument under
test, due to permanent heat dissipation caused by the thermowell. In temperature
applications fitted with static checking thermometers (e.g. pipeline systems), permanent
offsets in reference temperatures can also be caused by the measuring path.
Ambient temperatures around the indicator case which differ substantially from room
temperature can lead to steady indication errors with constant ambient temperatures
and to varying indication errors with fluctuating ambient temperatures.
Permanent indication errors caused by the ageing of the measuring system can be
ignored, as they only account for a fraction of the indication accuracy.
6.4 Zero adjustment
A zero adjustment may only be carried out by the manufacturer or in adequately equip-
ped workshops by qualified persons.
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The electrical connection must only be made by qualified skilled personnel.
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Connect the switch via cable terminal box.
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Conductor cross section max. 1.5 mm 2
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The terminal assignment is stated on the product label of the thermometer.
6. Commissioning, operation