Fluke 9116A, Руководство пользователя

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11 Maintenance
The calibration instrument has been designed with the utmost care. Ease of op-
eration and simplicity of maintenance have been a central theme in the product
development. Therefore, with proper care the instrument should require very
little maintenance. Avoid operating the instrument in an oily, wet, dirty, or
dusty environment.
•
If the outside of the instrument becomes soiled, it may be wiped clean
with a damp cloth and mild detergent. Do not use harsh chemicals on the
surface which may damage the paint.
•
Be sure that the well of the furnace is kept clean and clear of any foreign
matter.
DO NOT use fluids to clean out the well.
•
If a hazardous material is split on or inside the equipment, the user is re-
sponsible for taking the appropriate decontamination steps as outlined by
the national safety council with respect to the material.
•
If the mains supply cord becomes damaged, replace it with a cord of the
appropriate gauge wire for the current of the instrument. If there are any
questions, call Hart Scientific Customer Service for more information.
•
Before using any cleaning or decontamination method except those rec-
ommended by Hart, users should check with Hart Scientific Customer
Service to be sure that the proposed method will not damage the equip-
ment.
•
If the instrument is used in a manner not in accordance with the equip-
ment design, the operation of the furnace may be impaired or safety haz-
ards may arise.
•
The over-temperature cut-out should be checked every 6 months to see
that it is working properly. In order to check the user selected cut-out, fol-
low the controller directions (
Section 6 ) for setting the cut-out.
•
Adjustment of Temperature Uniformity: Vertical uniformity should be
measured in a freeze point cell just below the melting point of the cell.
The vertical temperature uniformity in the cell should be within the limit
specified in Section 2.1, Specifications, for a distance of 10.2 cm (4 in)
upwards from the bottom of the central well (See Figure 30 on page 74).
A periodic check of the temperature uniformity using a Type R or Type S
thermocouple is recommended at least once every year. If the vertical gra-
dient is not within the limit specified in Section 2.1, Specifications, the
heat pipe may not be functioning properly. Contact an Authorized Service
Center.
A properly operating heat pipe will keep the area around the cell or test
area uniform in temperature. However, the open end of the pipe can allow
some heat loss that can cause a gradient inside. Thermal shunts and insu-
lation are intended to inhibit this loss. On the other hand, the heat pipe re-
quires some heat loss at its top to promote condensation of the sodium
vapor. The balance may be adjusted by adjusting the amount of insulation
between the plates of the reflectors of the assembly that covers the access
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