English
TC57 Settings (Ethernet)
If a frame in TC57 format is received via the RS232 interface, it is sent immediately via the
Ethernet without a "timeout". This procedure clearly increases the performance of the
connection and ensures uninterrupted transmission of frames.
The user must select the required format and enter the values for "Fixed frame length" and
"User data length".
The value in the "Fixed frame length" edit box is in the range 2 to 255 bytes.
The value in the "User data length" edit box is in the range 2 to 14 bytes. The value only
refers to "User data" from the header.
Note: For the protocols IEC60870-5-103, VDEW or for the protocol used by DIGSI®, the
format FT 1.2 (Header length = 0 byte and Fixed Frame length = 2 byte) is required.
42 / 77
7XV5655-0BB00
The IEC 60870–5–1 and IEC
60870–5–2 standard defines four
standard frame formats for the data
link layer.
They are:
TC57 Format FT 1.1
TC57 Format FT 1.2
TC57 Format FT 2
TC57 Format FT 3
Frame formats FT 1.2, FT 2 and FT
3 have a frame of fixed length.
The frame with variable length for
FT 2 and FT 3 has a header of
fixed length. This contains "Start
character", "Length", "User data"
and "Checksum".
C53000-G1176-C175-2