Schweitzer Engineering SEL-387-0, Instruction Manual

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F.5
Date Code 20170601 Instruction Manual SEL-387-0, -5, -6 Relay
Unsolicited SER Protocol
Functions and Function Codes
Acknowledge
Message
The acknowledge message is constructed and transmitted for every received
message which contains a status byte with the LSB set (except another
acknowledge message) and which passes all other checks, including the CRC.
The acknowledge message format is shown below.
The SEL-387 supports the following response codes:
Examples
EXAMPLE F.1 Successful acknowledge for “Enable Unsolicited Data
Transfer” message from a relay with at least one of SER1, SER2, or
SER3 not set to NA:
A5 46 0E 00 00 00 00 00 00 81 00 XX cc cc
(XX is the same as the Response Number in the "Enable Unsolicited
Data Transfer" message to which it responds.)
EXAMPLE F.2 Unsuccessful acknowledge for “Enable Unsolicited
Data Transfer” message from a relay with all of SER1, SER2, and
SER3 set to NA:
A5 46 0E 00 00 00 00 00 00 81 02 XX cc cc
(XX is the same as the response number in the "Enable Unsolicited
Data Transfer" message to which it responds.)
EXAMPLE F.3 Disable Unsolicited Data Transfer message,
acknowledge requested:
A5 46 10 00 00 00 00 00 01 02 C0 XX 18 00 cc cc
(XX = 0, 1, 2, 3)
mmmmmmmm Four-byte time of day in milliseconds since midnight
FFFFFFFE Four-byte end-of-records flag
00000000 Element status (unused)
cccc Two-byte CRC-16 checkcode for message
Data Description
Data Description
A546 Message header
0E Message length (14 decimal)
0000000000 Five bytes reserved for future use as a routing address
00 Status byte (always 00)
XX Function code, echo of acknowledged function code with MSB set.
RR Response code (see below)
XX Response number (XX = 00, 01, 02, 03, 00, 01, ...) must match response
number from message being acknowledged.
cccc Two-byte CRC-16 checkcode for message
RR Response
00 Success
01 Function code not recognized
02 Function disabled