KEM TRICOR TCE80 -E Series, Руководство пользователя

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General Information
12
1.3.2 Accessories
Ordering Code Description
(Contact KEM) Connecting Cable TCM  TCE80xx-L-*
TRD8001 Additional remote display for the compact version
HSA96 DIN Rail Adaptor for TCE80**-L-*
IPS9-14 Protective front cover IP65 for TCE80**-L-*
1.4 Measuring Principle TCM
Two parallel flow tubes inside the TCM low meter are vibrating at their resonant frequency in opposite
direction. Any mass flow passing through the tubes will delay the vibration at the incoming side and
accelerate the vibration at the outgoing side. This causes a small time delay between both ends of the tube.
This time delay is measured and used to calculate the mass flow through the tubes.
By measuring the resonant frequency of the tubes the mass of the medium and - given a constant volume
inside the tubes - the specific gravity of the medium can be calculated.
As both effects are temperature dependent, the temperature is measured via a precise sensor for correcting
the temperature effects of flow and density measurement.
As a consequence a coriolis mass flow meter measures directly mass flow, density and temperature of the
medium. Knowing the mass flow and the density, also the volume flow can be calculated.
Fig. 3: Flections of the tubes with and without flow
Movement to the inside
no flow Movement to the inside
Fc direction with flow Movement to the outside
no flow and Movement to the outside
Fc direction with flow