GE MiCOM P40 Agile, Technical Manual, Page: 512 / 962

3.1.2 SETTING UP IM64
In this product, the feature that manages the fibre teleprotection command signals is called InterMiCOM 64 (or
IM64). IM64 is suitable for the exchange of all teleprotection command types.
Up to 2 banks of teleprotection command signals (IM64 signals) are provided. Each bank provides 8 duplex
command signals. That means that each bank assigns 8 bits for IM64 input signals and 8 bits for IM64 output
signals. Each bank is associated with a logical channel (referred to as Ch1 or Ch2 in the internal logic). Each logical
channel associates with a physical communications channel (labelled Ch1 or Ch2 at the physical connection point).
The association of logical channels to physical channels varies according to specific scheme configurations.
Action of each IM64 input signal is managed by attributes defined by three settings associated with it. These are
set in the PROT COMMS/IM64 column and are of the form:
● IM 1 Cmd Type (command type)
●
IM 1 FallBackMode (fallback modes)
● IM 1 DefaultValue (default values)
The settings shown above are for bit 1 only
The IM64 command type settings set the teleprotection type.
Permissive
satisfies the security requirements of
a permissive application, as well as the speed needed for a blocking scheme. For direct tripping applications, set it
to
Direct
.
The IM64fallback settings determine the behaviour of an input under communications failure conditions. You can
choose either to latch the state of the last good command received, or to revert to a default state. If you set the
fallback mode to
Default
you will need to set the default state to your requirement (either 1 or 0).
The attributes assigned to bit n of an IM64 input apply to that bit in both logical channels. For example, if IM4
DefaultValue is chosen as
1
then the default value for bit 4 in logical channel 1 (IM64 Ch1 Input 4) will be the same
for bit 4 in logical channel 2 (IM64 Ch2 Input 4), and will take the value 1.
3.1.3 TWO-TERMINAL IM64 OPERATION
The protection signalling connection requirement for products operating as a Two Terminal scheme is that the
Physical Channels labelled as Ch1 should be connected together. That means that the local Ch1 Tx connects to the
remote Ch1 Rx, and the local Ch1 Rx connects to the remote Ch1 Tx. Physical Channel 2 (Ch2) connectors may be
fitted, but they are not used.
The 8 bits of both Logical Channels (Ch1 and Ch2) are used. The bits of both Logical Channels are all assigned to
Physical Channel 1, so 16 duplex commands (IM64 Ch1 bits 1-8 and IM64 Ch2 bits 1-8) can be communicated
between terminals in IM64 messages using Ch1 Physical Channels.
3.1.4 DUAL REDUNDANT TWO-TERMINAL IM64 OPERATION
The protection signalling connection requirement for products operating as a Dual Redundant (Hot Standby)
scheme is that the Physical Channels labelled as Ch1 should be connected together and the Physical Channels
labelled as Ch2 should be connected together. That means that the local Ch1 Tx connects to the remote Ch1 Rx,
the local Ch1 Rx connects to the remote Ch1 Tx, the local Ch2 Tx connects to the remote Ch2 Rx, and the local Ch2
Rx connects to the remote Ch2 Tx.
The 8 bits of both Logical Channels (Ch1 and Ch2) are used. The bits of both Logical Channels are all assigned both
to Physical Channel 1 and to Physical Channel 2, so that 16 duplex commands (IM64 Ch1 bits 1-8 and IM64 Ch2
bits 1-8) can be communicated between terminals in IM64 messages with full redundancy of both Logical
Channels in the event of failure of either Physical Channel.
3.1.5 THREE-TERMINAL IM64 OPERATION
The protection signalling connection requirement for products operating as a Three Terminal scheme is that
Physical Channels labelled as Ch1 should be connected to Physical Channels labelled as Ch2. That means that a
Chapter 19 - Fibre Teleprotection P446SV
480 P446SV-TM-EN-1