Micom P634 - Connecting the IRIG-B Interface; Connecting the Serial Interfaces

5.6.2 Connecting the IRIG‑B Interface
An IRIG‑B interface for time synchronization may be installed as an optional
feature. It is connected by a BNC connector. A coaxial cable having a
characteristic impedance of 50 Ω must be used as the connecting cable.
5.6.3 Connecting the Serial Interfaces
5.6.3.1 PC Interface
The PC interface is provided so that personnel can operate the device from a
personal computer (PC).
WARNING
The PC interface is not designed as a permanent connection. Consequently,
the female connector does not have the extra insulation from circuits
connected to the system that is required per VDE 0106, part 101.
5.6.3.2 Communication Interfaces
The communication interfaces are provided as a permanent connection of the
device to a control system for substations or to a central substation unit.
Depending on the type, communication interface 1 on the device is connected
either by a special fiber-optic connector or an RS 485 interface with twisted pair
copper wires. Communication interface 2 is only available as an RS 485 interface.
The selection and assembly of a properly cut fiber-optic connecting cable
requires special knowledge and expertise and is therefore not covered in this
operating manual.
WARNING
The fiber-optic interface may only be connected or disconnected when the
supply voltage for the device is shut off.
An RS 485 data transmission link between a master and several slave devices
can be established by using the optional communication interface. The
communication master could be, for instance, a central control station. Devices
linked to the communication master, e.g. P634, are set-up as slave devices.
The RS 485 interface available on the P634 was designed so that data transfer in
a full duplex transmission mode is possible using a 4-wire data link between
devices. Data transfer between devices using the RS 485 interface is set up only
for a half duplex transmission mode. To connect the RS 485 communication
interface the following must be observed:
●
Only twisted pair shielded cables must be used, that are common in
telecommunication installations.
●
At least one symmetrical twisted pair of wires is necessary.
●
Conductor insulation and shielding must only be removed from the core in
the immediate vicinity of the terminal strips and connected according to
national standards.
●
All shielding must be connected to an effective protective ground surface at
both ends.
●
Unused conductors must all be grounded at one end.
5 Installation and Connection
P634
P634/EN M/R-42-A // P634‑311‑653 5-17