DH Instruments FPG8601, Руководство по эксплуатации и обслуживанию

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FPG8601™/VLPC™ OPERATION AND MAINTENANCE MANUAL
© 2007 DH Instruments, a Fluke Company Page 78
Figure 35. <Internal Limits> <Temperature>
Table 22. <Internal Limits> <Temperature>
Options
LABEL DESCRIPTION
Temperature re-
zero limit (°C)
(numeric entry field)
The number entered should represent the maximum
±
temperature
deviation allowed from the tare temperature. When this difference is
exceeded, a re-tare target message displays and a “T” will be included in
the run screen
<Status>
output.
Large temperature changes will cause zero drift in the FPG. For this
reason, the value entered should never exceed 1.0 °C. Typically .5 °C or
less is used.
Maximum
difference
between
temperature
sensors (°C)
(numeric entry field)
The maximum absolute difference between the mounting post temperature
and the lubricating volume temperature. The value is not intended to
monitor the calibration offset of the sensors. The goal is to make sure the
lubricating volume temperature is not changing relative to the mounting post
temperature. If this is the case, the FPG is in unstable temperature
conditions and should not be used until temperature stabilizes.
Maximum
temperature rate
of change (°C/s)
(numeric entry field)
Enter the maximum rate of change of either the mounting post or lubricating
volume temperature. Large temperature rates of change indicate unstable
conditions that will effect the overall stability of the load cell and resulting
FPG pressure.
Minimum
operating
temperature (°C)
(numeric entry field)
Enter the minimum temperature value for which the FPG temperature
compensation is valid. The FPG is temperature compensated over a
temperature range that is centered about 24 °C. Changes in temperature
around this range will not effect the FPG as long as the rate of change is
small and the FPG is zeroed when temperature changes significantly.
Maximum
operating
temperature (°C)
(numeric entry field)
Enter the maximum temperature value for which the FPG temperature
compensation is valid.
6.6.4.4 <HUMIDITY>
All limits related to humidity measurements by the humidity sensor located in the
lubricating volume are defined on this tab. Humidity is nominally controlled to
50 % during assembly by adjusting the proper regulators. As long as the
bubbling system is filled with water (see Section 8.2) and the FPG is purged
when changing measurement modes, the humidity should stay within the
required limits. The purpose of each limit is defined in Table 23.
When a humidity limit is exceeded a “H” will be listed in the <Status>
category of the <Diagnostics Display>.
This forces a “Not Ready” condition.