User Manual
Arctic Substation Gateway
Firmware Version 2.4.x
38
Document Version 1
7.4
IEC-104 Settings
The IEC-104 settings define the properties of IEC-104 link layer and
application layer parameters as described in the IEC 60870-5-104 standard.
The IEC-104 communication is carried out between the Arctic and the IEC-104
master over the TCP/IP network.
Figure 29. IEC-104 Settings
TX window size (k)
TX window size defines the maximum number of I format APDUs the Arctic
may send before requiring the IEC-104 master to acknowledge them. If there
are k unacknowledged frames sent the Arctic will stop polling IEC-101 slave
for events until acknowledgement is received.
Table 28: IEC-104 TX windows size (k)
IEC-104 TX windows size (k)
Type
Window size
Units
Packets
Value
range
1-20
Note
The k must be always less than the maximum sequence number
defined below. The IEC-104 standard suggests k to be 12.
RX window size (w)
It defines the maximum number of I format APDUs the Arctic may receive
before sending acknowledgement to the IEC-104 master.
Table 29: IEC-104 RX windows size (w)
IEC-104 RX windows size (w)
Type
Window size
