ABB Relion 670 2.0 IEC Series, Руководство по установке

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The distance between connection points should be < 1200 m (3000 ft), see Figures 48
and 49 . Only the outer shielding is connected to the IED with the cable clamp, shown
in Figure 30 . The cable shield shall be properly connected to the IED chassis with the
cable clamp, where the maximum open conductor length is 40 mm (1.57”) between
clamp and terminals, see Figure
30 . If double shielded cable is used, the inner cable
shielding should be connected at the external equipment end only. At the IED terminal
end, the inner shield should be isolated. The inner and outer shieldings are connected
to the external equipment according to the installation instructions for the actual
equipment. Use insulating tape for the inner shield to prevent contact with the IED
chassis. Make sure that the IEDs are properly earthed with as short connections as
possible from the earth screw, for example to an earthed frame.
The IED and the external equipment should preferably be connected to the same
battery.
Cc Cc
1)
External
Equipment (PC)
PE 1) 3)
2)
4)
IED
X1
1 6 5 4 3 2
IED
1 6 5 4 3 2
X1
4)
IEC13000229-1-en.vsd
3)
IEC07000141 V2 EN
Figure 48: Communication cable installation, 2-wire
Where:
1
The inner shields shall be connected together (with an isolated terminal block) and only have
one connection point in the whole system, preferably at the external equipment (PC).
The outer shield shall be connected to the IED chassis in every cable end. Use the shield
connection clamp at all IEDs. The first IED will have only one cable end but all others require
two.
2 Connect according to installation instructions for the actual equipment, observe the 120 ohms
termination.
3 Connect the screens according to the installation instructions for the actual equipment.
4 Shield connection clamp, see Figure 30 .
Cc Communication cable
1MRK514019-UEN A
Section 6
Connecting
670 series 2.0 IEC 75
Installation manual