
125
Reference Manual
00809-0100-4811, Rev DA
Appendix A: Reference Data
January 2015
Reference Data
Rosemount 3301 in applications where the probe is fully submerged in the liquid. If interface is
to be measured, follow these criteria:
The dielectric constant of the upper product must be known and should not vary. The
RCT software has a built-in dielectric constant calculator to assist the user in
determining the dielectric constant of the upper product.
The dielectric constant of the upper product must have a lower dielectric constant than
the lower product to have a distinct reflection.
The difference between the dielectric constants for the two products must be larger
than 10.
Max. dielectric constant for the upper product is 10 for the coaxial probe and 5 for twin
lead probes.
The upper product thickness must be larger than 8 in. (0.2 m) for the flexible twin lead
probe; 4 in. (0.1 m) for the rigid twin lead, and coaxial probes in order to distinguish the
echoes of the two liquids.
Sometimes there is an emulsion layer (mix of the products) between the two products
which can affect interface measurements. For guidelines on emulsion situations,
consult your local Emerson Process Management representative.
Figure A-11. Interface Measurement with a Rosemount 3302 and a Rosemount 3301 (Fully
Submerged Probe)
Table A-1. Temperature Ranges for Standard Tank Seals with Different O-ring Materials
Note
Always check the chemical compatibility of the O-ring material with your application.
Tank seal with different O-ring material Min. temperature °F (°C) in air Max. temperature °F (°C) in air
Viton
®
Fluoroelastomer 5 (-15) 302 (150)
Ethylene Propylene -40 (-40) 266 (130)
Kalrez
®
6375 Perfluoroelastomer 14 (-10) 302 (150)
Nitrile Butadiene (NBR) -31 (-35) 230 (110)
Level
Interface Level
Level = Interface Level
Comentários a estes Manuais