ABB COPA-XE, Инструкционный бюллетень

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3
Electromagnetic Flowmeter
COPA-XE / MAG-XE
2. Assembly and Installation
2.1 Inspection
Before installing the electromagnetic flowmeter system check
for mechanical damage due to possible mishandling during
shipment. All claims for damage are to be made promptly to the
shipper before installing the flowmeter.
2.2 Flowmeter Primary Installation Requirements
The flowmeter primary should not be installed in the vicinity of
strong electromagnetic fields.
The electromagnetic flowmeter primary must be installed so
that the metering tube is always filled with fluid. Valves or other
shut off devices should be installed downstream from the EMF.
A slight pipeline slope of approx. 3 % is desirable for preventing
gas build up within the meter (Fig. 2).
Vertical installations are ideal when the fluid flows in an upward
direction. Installations in drop lines, i.e. the fluid flows from the
top to the bottom are to be avoided because experience has
shown that it is not possible to guarantee that the pipeline will
remain full and that an equilibrium condition between the
upward flowing gas and the downward flowing liquid will not
occur (Fig. 3).
The flowmeter primary should generally be installed so that the
electrical connectors (Pg or NPT) point downward (Figs. 3 & 5).
In horizontal installations the imaginary line connecting the
electrodes should be horizontal so that air or gas bubbles
cannot influence the signal voltage. The electrode orientation is
shown in Fig. 4.
For a free flow in- or outlet an invert should be provided to
assure that the flowmeter primary is always filled with fluid
(Fig. 5).
Fig. 2
Fig. 3
Imaginary
Electrode Axis
Fig. 4
Fig. 5