Alstom MiCOM P54 Series, Technical Manual

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SCADA Communications P54x/EN SC/La4
MiCOM P543, P544, P545 & P546 (SC) 13-23
SC
3.4 Spontaneous events
Events are categorized using the following information:

Function type

Information number
The IEC 60870-5-103 profile in the Relay Menu Database,
P54x/EN MD
, contains a
complete listing of all events produced by the relay.
3.5 General interrogation
The GI request can be used to read the status of the relay, the function numbers, and
information numbers that will be returned during the GI cycle are indicated in the
IEC 60870-5-103 profile in the Relay Menu Database,
P54x/EN MD
.
3.6 Cyclic measurements
The relay will produce measured values using ASDU 9 on a cyclical basis, this can be read
from the relay using a Class 2 poll (note ADSU 3 is not used). The rate at which the relay
produces new measured values can be controlled using the measurement period setting.
This setting can be edited from the front panel menu/front Courier port and is active
immediately following a change.
It should be noted that the measurands transmitted by the relay are sent as a proportion of
2.4 times the rated value of the analog value.
3.7 Commands
A list of the supported commands is contained in the Relay Menu Database,
P54x/EN MD
.
The relay will respond to other commands with an ASDU 1, with a cause of transmission
(COT) indicating ‘negative acknowledgement’.
3.8 Test mode
It is possible using either the front panel menu or the front Courier port to disable the relay
output contacts to allow secondary injection testing to be performed. This is interpreted as
‘test mode’ by the IEC 60870-5-103 standard. An event will be produced to indicate both
entry to and exit from test mode. Spontaneous events and cyclic measured data transmitted
whilst the relay is in test mode will have a COT of ‘test mode’.
3.9 Disturbance records
The disturbance records are stored in uncompressed format and can be extracted using the
standard mechanisms described in IEC 60870-5-103.
Note:
IEC 60870-5-103 only supports up to 8 records.
3.10 Blocking of monitor direction
The relay supports a facility to block messages in the monitor direction and also in the
command direction. Messages can be blocked in the monitor and command directions using
the menu commands, Communications - CS103 Blocking - Disabled/Monitor Blocking/
Command Blocking or DDB signals Monitor Blocked and Command Blocked.