beautypg.com

Probe type, Product dielectric, Vapor dielectric – Emerson Guided Wave Radar Level and Interface Transmitters 3300 User Manual

Page 62: Rosemount 3300 series

background image

Reference Manual

00809-0100-4811, Rev CA

February 2006

Rosemount 3300 Series

4-10

Probe Type

The transmitter automatically makes an initial calibration based on the type of
probe that is used. This parameter is pre-configured at factory and only needs
to be set if the probe is changed to another type. Choose one of the following
options:

Rigid Twin

Flexible Twin

Coaxial, Coaxial HP, Coaxial HTHP

Rigid Single, Rigid Single HTHP, Rigid Single PTFE

Flexible Single, Flexible Single HTHP, Flexible Single PTFE

NOTE
Flexible and Rigid probes require different radar electronics and can not be
used with the same transmitter head.

Product Dielectric

For interface measurements the dielectric constant of the upper product is
essential for calculating the interface level and the upper product thickness.
By default the Product Dielectric parameter is about 2.

If the dielectric constant of the lower product is significantly smaller than the
dielectric constant of water, you may need to make special adjustments. See
section “Interface Measurements for Semi-Transparent Bottom Products” on
page 6-5
fo
r further information.The dielectric constant of the product is used
for setting the appropriate signal amplitude thresholds, see Section 6: Service
and Troubleshooting
fo
r more information on amplitude threshold settings.
Normally this parameter does not need to be changed for level
measurements. However, for some products measurement performance can
be optimized by setting the proper product dielectric constant.

The Rosemount Configuration Tool (RCT) software includes a Dielectric Chart
which lists the dielectric constants of a wide range of products. RCT also
includes a tool which allows you to calculate dielectric constants based on
measurements of the Upper Product Thickness.

Vapor Dielectric

In some applications there is heavy vapor above the product surface having a
significant influence on the level measurement. In such cases the vapor
dielectric can be entered to compensate for this effect.

The default value is equal to 1 which corresponds to the dielectric constant of
vacuum. Normally this value does not need to be changed since the effect on
measurement performance is very small for most vapors.

HART Comm

1, 3, 2, 3

HART Comm

1, 3, 3, 3

HART Comm

1, 3, 3, 2