Alstom MiCOM P54 Series, Technical Manual

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P54x/EN IN/La4 Installation
(IN) 15-10 MiCOM P543, P544, P545 & P546
IN
6.6 Ethernet port for DNP3.0 (if applicable)
Fiber Optic Port
The relays can have 100 Mbps Ethernet port. Fiber optic connection is recommended for
use in permanent connections in a substation environment. The 100 Mbit port uses type ST
(BFOC2.5) connectors, compatible with 50/125 µm or 62.5/125 µm multimode fibers for use
at 1300 nm wavelength.
RJ-45 Metallic Port
The user can connect to either a 10Base-T or a 100Base-TX Ethernet hub; the port will
automatically sense which type of hub is connected. Due to possibility of noise and
interference on this part, it is recommended that this connection type be used for short-term
connections and over short distances. Ideally, the relays and hubs should be located in the
same cubicle.
The connector for the Ethernet port is a shielded RJ-45. The table shows the signals and
pins on the connector.
Pin Signal name Signal definition
1 TXP Transmit (positive)
2 TXN Transmit (negative)
3 RXP Receive (positive)
4 - Not used
5 - Not used
6 RXN Receive (negative)
7 - Not used
8 - Not used
Table 5: Signals on the Ethernet connector
6.7 Download/monitor port
Short term connections to the download/monitor port, located behind the bottom access
cover, can be made using a screened 25-core communication cable up to 4 m long. The
cable should be terminated at the relay end with a 25-way, metal shelled, D-type male plug.
6.8 Earth connection
Every relay must be connected to the cubicle earth bar using the M4 earth studs in the
bottom left hand corner of the relay case. The minimum recommended wire size is 2.5 mm
2
and should have a ring terminal at the relay end.
To prevent any possibility of electrolytic action between brass or copper earth conductors
and the rear of the relay, precautions should be taken. Examples include placing a
nickel-plated washer between the conductor and the relay case, or using tinned ring
terminals.