User Manual
Arctic Substation Gateway
Firmware Version 2.4.x
40
Document Version 1
IEC-104 link test interval (t3)
Note
Adjust this parameter according to the criticality of the link. The
IEC-104 standard suggests 20 seconds but for pay-per-use GPRS
connections the practical value may be substantially longer.
Suspended timeout
This defines the time in seconds how long a connected IEC-104 link can be in
suspended state (STOPD) before the Arctic closes the connection.
Table 33: IEC-104 suspended timeout
IEC-104 suspended timeout
Type
Timeout
Units
Seconds
Value range
1-65000
Note
Using this parameter increases the probability of detecting partially
closed network connections especially in UDP mode.
Max sequence number
These are the maximum sequence number used in IEC-104 communication.
The value zero selects the standard value 32767.
Table 34: IEC-104 suspended timeout
IEC-104 suspended timeout
Type
Sequence number
Units
Packets
Value range
1-32767
Note
0 = 32767 as suggested by the IEC-104 standard.
Cause of transmission length (IEC-104)
It defines the length of IEC-104 Cause of transmission ASDU header field in
bytes.
Table 35: IEC-104 ASDU cause of transmission length
IEC-104 ASDU cause of transmission length
Type
Field length
Units
Bytes
Value range
1-3
Note
The IEC-104 standard defines value 2.
Common address length (IEC-104)
This defines the length of IEC-104 Common address ASDU header field in
bytes.