K.8
SEL-311C Relay Instruction Manual Date Code 20060320
Unsolicited Fast SER Protocol
Functions and Function Codes
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)
4. Successful acknowledge from the relay for the “Disable
Unsolicited 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 Data Transfer” message to which it responds.)
5. Successful acknowledge message from the master for a Fast
SER message.
A5 46 0E 00 00 00 00 00 00 98 00 XX cccc
(XX is as same as the response number in the Fast SER
message to which it responds.)
Notes:
Once the relay receives an acknowledge with response code 00 from the
master, it will clear the settings changed bit (bit 1) in its status byte, if that bit
is asserted, and it will clear the settings changed bit in Fast Meter, if that bit is
asserted.
An element index of FE indicates that the SER record is due to power up. An
element index of FF indicates that the SER record is due to setting change. An
element index of FD indicates that the element identified in this SER record is
no longer in the SER trigger settings.
When the relay sends an SER message packet, it will put a sequential number
(0, 1, 2, 3, 0, 1, ...) into the response number. If the relay does not receive an
acknowledge from the master before approximately 500 mS, the relay will
resend the same message packet with the same response number until it
receives an acknowledge message with that response number. For the next
SER message, the relay will increment the response number (it will wrap
around to zero from three).
A single SER message packet from the relay can have a maximum number 32
records and the data may span a time period of no more than 16 seconds. The
master may limit the number records in a packet with the third byte of
function code data in the “Enable Unsolicited Data Transfer” message
(function code 01). The relay may generate a Fast SER packet with less than
the requested number of records, if the record time stamps span more than 16
seconds.
The relay always requests acknowledgment in Fast SER messages (LSB of the
status byte is set).
Fast SER messages can be enabled on multiple ports simultaneously.