Baer DLX User Manual page 146

2 IEC 60870-5-102 Protocol
Apart from the SCTM protocol, the protocol according to IEC 60870-5-102
can also be used for data retrieval.
2.1 Telegram processing
•
Transmission settings: 8, E, 1 (1 start bit, 8 data bits, even parity, 1 stop
bit)
•
Only telegrams according to IEC 60870-5-1 format FT 1.2 are supported.
•
Only asymmetrical transmission procedures according to section 5 of IEC
60870-5-2 are applied. The basic polling procedure uses the re-
quest/respond service with function code 11 for data retrieval of class 2.
Data of class 1 is indicated by the ACD bit. Values of the most recent regis-
tration period are assigned to class 2, whereas values from previous regis-
tration periods and all information requested by the polling ASDU are
assigned to class 1.
•
The link address (address field of the link or connection layer) must have 2
bytes ( fixed system parameter)
•
The counter address (the common ASDU address) must have 2 bytes (
and can be identical to the link address).
•
The maximum telegram length is 256 byte.
•
Telegrams with wrong link address, wrong checksum or wrong format are
discarded.
2.2 Date retrieval (Periodic buffers Tm1/MP1 & Tm2/MP2)
You can retrieve current data (from the most recent registration period :=
class 2), data from the oldest registration period and any complete registra-
tion period, data from a selected time period as well as the manufacturer
information.
The following selection was made from the user standard IEC 60870-5-3/4:
•
All values are transferred per buffer either as "Billing data" or as "„opera-
tional data" (You can program this using DLXPARA).
•
A maximum of two registration periods (MP1 and MP2) are supported.
•
The register addresses are entered in ascending numerical order (the se-
quence is defined by the device parameters set using DLXPARA: inputs
are entered before totals).
•
Under the heading "periodically reset readings" either energy increments
(e.g. kWh) or demand values (e.g. kW) will be transferred, depending on
the parameters set with DLXPARA.
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