Honeywell SLG 700 Option Manual page 148

6.6.2.4 Process
The four parameters in this group allow the products involved in the process of operating the tank to be
identified, as shown. The first consideration to be made is the number of products involved, and
secondly the dielectric constant of each product. The dielectric constant of a medium affects radar
measurements in two ways:
1. Pulses travelling through a medium are slowed by an amount related to the dielectric constant.
2. The relative amount of the original pulse that is reflected from the boundary between two mediums
is related to the dielectric constants of the media on each side of the interface. For the reflected
pulse, the reduction in the amplitude with respect to the original pulse amplitude can be calculated
from the dielectric constants of the media on each side of the interface.
Common dielectric constants can be found from the pull-down lists. If a material is not present on the
list or if the dielectric constant is not correct, the correct value can be input in the box.
Page 132 FOUNDATION Fieldbus Option User's Guide Rev. 3.0