scheider electric MiCOM P746, Technical Manual

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Firmware Design P746/EN FD/G31
MiCOM P746 (FD) 9-
3
1. RELAY SYSTEM OVERVIEW
1.1 Hardware overview
The relay hardware is based on a modular design whereby the relay is made up of an
assemblage of several modules that are drawn from a standard range. Some modules are
essential while others are optional depending on the user’s requirements.
The modules and the processor boards form a network. A data bus, used for data exchange
and address selection, links this network. The processor controls and drives the input/output
boards and the other modules of the relay. The following figure illustrates the data exchange.
Relay Boards
(standard)
Analogue
input board
Relay boards
(high break)
Power Supply
IRIG-B/
Ethernet /
Comms
Board
(Optional)
P3701ENc
Main board
Interconnexion buses
ENTER
READ
=
=
CLEAR
OUT OF SERVICE
HEALTHY
=
TRIP
ALARM
FIGURE 1: MiCOM P746 ARCHITECTURE
The different modules that can be present in the relay are as follows:
FD
1.1.1 Processor board (Main board)
The main board performs some functions for the relay (fixed and programmable scheme
logic…) and controls the operation of modules which are on its interconnection bus within the
relay. The main board also contains and controls the user interfaces (LCD, LEDs, keypad
and communication interfaces).
1.1.2 Analogue Input module
The input module converts the information contained in the analogue or digital input signals
into a format suitable for the co-processor board. The standard input module consists of two
boards:
•
a Current transformer board to provide electrical isolation
•
a main input board which provides analogue to digital conversion and the isolated digital
inputs.