Rosemount TankRadar Rex DAU 2100, Руководство по обслуживанию

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4-1
Rosemount Tank Radar Rex
Chapter 4 Service
Service Manual
308012En, Ed.2
May 2013
4. Service
4.1 Rex RTG
4.1.1 How to initiate an echo search
There are several ways that an echo search can be initiated:
• Switch power supply off and on. A search is automatically per-
formed.
• Restart the RTG:
1 Select the transmitter icon in the TankMaster WinSetup
workspace window.
2 Click the right mouse button and choose the Restart option
or-
from the
Service menu choose Devices/Restart.
What happens after a power on?
1 An internal check of software version and memory status is done.
2 The communication is enabled.
3 The sweep generation is started. A “dummy” sweep is generated until
the sweep is linear (warm-up mode).
4 The level gauging starts with a search through the tank to find the level of
the product.
5 When the level is found, the normal gauging procedure starts.
What happens during a search?
A microwave signal is sent towards the product surface with a
continuously varying frequency. The reflected signal is mixed with the
outgoing signal, resulting in a low-frequency signal which is proportional
to the distance to the liquid surface. By using a signal processing
technique based on Fast Fourier Transformation (FFT), a frequency
spectrum of all echoes in the tank is obtained. From this spectrum the
surface level is extracted with high accuracy.