Endress+Hauser Gammapilot M FMG60 - Page 113

Gammapilot M FMG60 with FOUNDATION Fieldbus Appendix
Endress+Hauser 113
11.4.4 Density or concentration measurement (4)
A gamma radiation source and a Gammapilot M are mounted on opposite sides of a measuring tube.
The Gammapilot M calculates the density or concentration of the medium from the intensity of the
received radiation. The unit can be freely selected.
If an additional temperature sensor (5) is connected, the Gammapilot M accounts for the thermal
expansion of the medium. That means, it does not output the measured density directly. Instead it
calculates the density which the medium would have at a certain standard temperature defined by
the user.
Furthermore, the density signal of the Gammapilot M can be combined with the signal of a volume
flow meter (6), e.g. Promag 55S. From these two signals it is possible to calculate the mass flow.
11.4.5 Gamma Modulator FHG65 (option)
In a radiometric measuring point with Gammapilot FMG60, the Gamma Modulator FHG65 is
mounted in front of the radiation exit channel of the source container. It contains a shaft slotted
along the longitudinal axis. This shaft rotates continuously and alternately screens off the gamma
beam at a frequency of 1 Hz or allows it through.
Due to this frequency, the useful beam differs from fluctuating ambient interference radiation and
from interference radiation occurring sporadically (e.g. from nondestructive material testing). Using
a frequency filter, the Gammapilot M FMG60 can thus separate the useful signal from interference
radiation. In this way, it is possible to continue measuring even if interference radiation occurs,
which, in turn, increases the measuring certainty and system availability.
For details please refer to Technical Information TI423F.
L00-FHG65xxx-15-00-00-xx-001
1: Interference radiation
!
Note!
The Gamma Modulator FHG65 and the Gammapilot M FMG60 are not interconnected electrically.
When commissioning the Gammapilot FMG60, the "beam type" (*02) parameter must be set to
"modulated".
Gammapilot M FMG60
FHG65
FQG61
FQG62
1