GE MiCOM P40 Agile, Техническое руководство, Страница: 633 / 962

4.2 POWER SUPPLY CONNECTIONS
These should be wired with 1.5 mm PVC insulated multi-stranded copper wire terminated with M4 ring terminals.
The wire should have a minimum voltage rating of 300 V RMS.
Caution:
Protect the auxiliary power supply wiring with a maximum 16 A high rupture capacity
(HRC) type NIT or TIA fuse.
4.3 EARTH CONNNECTION
Every device must be connected to the cubicle earthing bar using the M4 earth terminal.
Use a wire size of at least 2.5 mm
2
terminated with a ring terminal.
Due to the physical limitations of the ring terminal, the maximum wire size you can use is 6.0 mm
2
using ring
terminals that are not pre-insulated. If using pre insulated ring terminals, the maximum wire size is reduced to 2.63
mm
2
per ring terminal. If you need a greater cross-sectional area, use two wires in parallel, each terminated in a
separate ring terminal.
The wire should have a minimum voltage rating of 300 V RMS.
Note:
To prevent any possibility of electrolytic action between brass or copper ground conductors and the rear panel of the product,
precautions should be taken to isolate them from one another. This could be achieved in several ways, including placing a
nickel-plated or insulating washer between the conductor and the product case, or using tinned ring terminals.
4.4 WATCHDOG CONNECTIONS
These should be wired with 1 mm PVC insulated multi-stranded copper wire terminated with M4 ring terminals.
The wire should have a minimum voltage rating of 300 V RMS.
4.5 EIA(RS)485 AND K-BUS CONNECTIONS
For connecting the EIA(RS485) / K-Bus ports, use 2-core screened cable with a maximum total length of 1000 m or
200 nF total cable capacitance.
To guarantee the performance specifications, you must ensure continuity of the screen, when daisy chaining the
connections.
Two-core screened twisted pair cable should be used. It is important to avoid circulating currents, which can cause
noise and interference, especially when the cable runs between buildings. For this reason, the screen should be
continuous and connected to ground at one end only, normally at the master connection point.
The K-Bus signal is a differential signal and there is no signal ground connection. If a signal ground connection is
present in the bus cable then it must be ignored. At no stage should this be connected to the cable's screen or to
the product’s chassis. This is for both safety and noise reasons.
A typical cable specification would be:
●
Each core: 16/0.2 mm
2
copper conductors, PVC insulated
●
Nominal conductor area: 0.5 mm
2
per core
● Screen: Overall braid, PVC sheathed
P446SV Chapter 23 - Installation
P446SV-TM-EN-1 601