Rosemount 5300 Series, Справочное руководство

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Specifications and Reference Data
May 2016
Reference Manual
00809-0100-4530, Rev DD
230
Specifications and Reference Data
A.2.4 Accuracy over measuring range
The measuring range depends on probe type, dielectric
constant of the product and installation environment, and
is limited by the Blind Zones at the very top and bottom of
the probe. In the Blind Zones, the accuracy exceeds ±1.18
in. (30 mm), and measurements may not be possible.
Measurements close to the Blind Zones will have reduced
accuracy.
The following conditions will impact the Blind Zones:

If the single lead probes or twin probes are installed in a
nozzle, the nozzle height shall be added to the specified
Upper Blind Zone.

The measuring range for the PTFE covered Flexible Single
Lead probe includes the weight when measuring on a
high dielectric media.

When using a metallic centering disc, the Lower Blind
Zone is 8 in. (20 cm), including weight if applicable.
When using a PTFE centering disc, the Lower Blind Zone is
not affected.
Figure A-12 , Figure A-13 , and Figure A-14 illustrate the
accuracy over measuring range at reference condition with
alternating probe types and varying dielectric constant of
the product.
Figure A-11. Blind Zones
Note
Measurements may not be possible in the Blind Zones, and
measurements close to the Blind Zones will have reduced
accuracy. Therefore, the 4-20 mA points should be
configured outside these zones.
Figure A-12. Accuracy Over Measuring Range for Single Lead Probes
(Rigid, Segmented Rigid, and Flexible)
Upper Blind Zone
Lower Blind Zone
Reduced accuracy
Reduced accuracy
±
0.12 in.
(3 mm)
3.9 in. (10 cm)
9.8 in. (25 cm)
0.4 in. (1 cm)
±
1.18 in.
(30 mm)
±
0.12 in.
(3 mm)
3.5 in. (9 cm)
9.8 in. (25 cm)
4.7 in. (12 cm)
±
1.18 in.
(30 mm)
Accuracy
Accuracy
Blind Zone
Water (DC = 80) Oil (DC = 2)