Baer DLX - 1 SCTM Protocol

A 5
1 SCTM Protocol
The following sections describe the data format of telegrams during com-
munication using the SCTM protocol (Serial Coded Telemetering). The fol-
lowing conditions have to be observed:
• transmission settings: 7 (bits), e (even parity), 1 (stop bit)
• the substation address (US-Number) has 5 digits (can be programmed us-
ing DLXPARA) or 8 digits (from version 1.04.01 and up)
• no point-to-point connection is possible without substation address
• the length of the header is constant: 14 (or 17) bytes
• broadcast commands and priority telegrams are not supported
• a maximum of two registration periods (MP1/Tm1 and MP2/Tm2) is sup-
ported
The following data can be retrieved:
• load profile data from registration period buffers (PP-01 for MP1 and PP-02
for MP2) with a maximum of 16 channels (demand, energy values or in-
crements/energy feed) per buffer and registration period
• spontaneous event data, including alarm messages, status messages and
parameter changes
• table data (addresses between 000-00 and 999-99)
1.1 Device status in the registration period data block
The DLX stores the device status for each completed registration period;
this data contains general information about the unit for that period. It con-
sists of 4 ASCII characters, representing 2 bytes (2 characters per byte).
Each character is coded in the hexadecimal system and contains 4 bits.
The following table describes the relations between the hexadecimal nota-
tion and the binary notation:
Hex Binary Hex Binary Hex Binary Hex Binary
0 0000 4 0100 8 1000 C 1100
1 0001 5 0101 9 1001 D 1101
2 0010 6 0110 A 1010 E 1110
3 0011 7 0111 B 1011 F 1111
In the DLX unit the device status is contained in 2 bytes:
Byte 1 Byte 2
Character 1 Character 2 Character 3 Character 4
T-Bit U-Bit M-Bit A-Bit S-Bit 0 NP-Bit L-Bit 0 1 0 0 0 0 0 0