ABB COPA-XE, Инструкционный бюллетень

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Electromagnetic Flowmeter
COPA-XE / MAG-XE
9.2 Signal and Excitation Cable Connections for
Model MAG-XE
The Electromagnetic Flowmeter primary is connected to its
converter by a cable. The magnet coil supply voltage of
≤
12 V
DC is provided from terminals M1/M2. The signal/excitation
cable is connected to the flowmeter primary at terminals 1, 2,
M1, M2, 3, SE. A description of the connections is shown in
Fig. 29. The shield 3 is connected to common at the flowmeter
which is connected to ground internally. The ground connection
on the outside of the flowmeter primary is also to be connected
to ground.
9.2.1 Signal and Excitation Cable Construction
The signal/excitation cable conducts signals of only a few
millivolts and should be routed in the shortest manner. The
maximum allowable cable length is 50 m.
The cables should not be routed in the vicinity of large electrical
machinery and switch gear equipment which could induce stray
fields, pulses and voltages. All leads are to be shielded and
their shields connected to ground B. The signal cable should
not be fed through branch fittings or terminals strips. A shielded
excitation cable is located parallel to the signal leads in the
cable assembly so that only one cable is required between the
flowmeter primary and the converter. To shield against
magnetic pickup the cable incorporates an outer steel shield
which is to be connected to the SE Terminals.
!
Note:
If plant conditions make it impossible to avoid proximity
to electrical machinery or switch gear equipment, it is
advisable to route the signal/excitation cable in metallic
conduits which are connected to ground B.
9.2.2 Flowmeter Primary Connection Area
The leads of the signal/excitation cable should be routed in the
shortest manner to the connection terminals. Cable loops are to
be avoided (see Fig. 29).
1 PVC jacket, white
2 Woven steel shield,
natural,
∅
0.15 mm
3 Woven Cu shield,
natural,
∅
0.13 mm
4 Flow signal
∅
0.75 mm
jackets, red & blue
5 Excitation, jacket, white
6 1x shield each, woven Cu
shield, natural,
∅
0.1 mm
7 Polyethylene, natural
ABB No. D173D018U02
Fig. 29 Signal Cable Construction
Terminal Designations Connections
1 + 2
3
M1 + M2
SE
Flow signal leads (red & blue)
Inner cable shield (Copper)
Signal potential
Magnetic field excitation connections
Outer cable shield (steel)
red
blue
Ground Connection
SE-Terminal
Signal Cable
white
Fig. 30 Flowmeter Primary Connection Area