Schweitzer Engineering Laboratories SEL-351-5, Instruction Manual

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J.7
Date Code 20070117
Instruction Manual SEL-351-5, -6, -7 Relay
SEL-351 Fast SER Protocol
Functions and Function Codes
Acknowledge
Message Sent from
Master to Relay, and
From Relay to Master
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 in
Table J.4 .
The SEL-351 supports the following response codes:
Examples
1. Successful acknowledge for “Enable Unsolicited Fast SER
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 as same as the Response Number in the “Enable
Unsolicited Data Transfer” message to which it
responds)
2. Unsuccessful acknowledge for “Enable Unsolicited Fast SER
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 as same as the response number in the “Enable
Unsolicited Data Transfer” message to which it
responds.)
3. Disable Unsolicited Fast SER 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)
4. Successful acknowledge from the relay for the “Disable
Unsolicited Fast SER Data Transfer” message:
A5 46 0E 00 00 00 00 00 00 82 00 XX cc cc
(XX is as same as the response number in the “Disable
Unsolicited Fast SER Data Transfer” message to which
it responds.)
Table J.4 Acknowledge Message Format
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
Table J.5 SEL-351 Response Codes
RR Response
00 Success
01 Function code not recognized