Enraf Tanksystem HERMetic UTImeter Rtex, Руководство по эксплуатации и обслуживанию

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50455/RTEX/0807 UTImeter Rtex
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9.10 Temperature verification
The temperature calibration curve is stored in the sensor memory and cannot be modified. The calibration is
set once at the factory and do not require subsequent adjustment.
Nevertheless it is recommended to check the temperature accuracy once a year. A one point check is
enough to qualify the sensor.
9.10.1 Equipment required
-
A Dewar flask or any vacuum flask, approximately 8 cm in diameter and 36 cm deep.
-
Ice, preferably made from distilled water.
-
Water, preferably distilled and precooled.
9.10.2 Preparing the Ice Point bath
(1) Shave or crush the ice into small pieces, avoiding direct contact with the hands or any unclean object.
The pieces shall be no more then 5 mm.
(2) Fill the Dewar flask with the crushed ice and add sufficient water to form a slush, just filling the voids
between ice particles but not enough to float the ice.
(3) Insert the sensor, packing the ice gently about it.
(4) Let it stand for half an hour to permit the sensor temperature, the ice particles and the water to
equilibrate.
(5) As the ice melts it will be necessary to drain off some water and add more crushed ice. Gently stir the ice
with the sensor periodically to assist equilibration.
IMPORTANT NOTE
: Attention to detail during the preparation of the Ice Point bath is critical to the accuracy
and quality of the offset verification.
9.10.3 Checking the UTImeter
(6) After 30 minutes have elapsed, gently stir the bath with the sensor again to ensure complete equilibration
of temperature.
(7) Switch on the UTImeter.
(8) Observe the reading. It should be

0.10 °C (

0.20 °F) The temperature must be stable, i.e. within

0.04
°C (

0.07 °F).
(9) If it is not OK, refer to section 10 "Trouble shooting".