Making The Screen Connection - ABB REL670 Installation And Commissioning Manual

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Making the electrical connection
The cubicle must be properly connected to the station earthing system. Use a conductor with a
core cross section area of at least 4 mm
2
1
where:
1 is main protective earth to chassis
2 is earthing screw to Power Supply Module
3 is earthing screw to TRM. (There is one earth connection per TRM)
Figure 18: Rear view of IED with one TRM showing earthing points.

Making the screen connection

When using screened cables always make sure screens are earthed and connected according to
applicable engineering methods. This may include checking for appropriate earthing points near
the IED, for instance, in the cubicle and/or near the source of measuring. Ensure that earth con-
nections are made with short (max. 10 cm) conductors of an adequate cross section, at least 6
2
mm (AWG10) for single screen connections.
2
(AWG 12).
en05000509.vsd
Chapter 5
Installing the IED
3