Vega Absolute M-BUS-1, Руководство пользователя

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M-BUS-1 / User Manual
27
Revision 10
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27 May 2019
5 COMMUNICATION PROTOCOL
This part describes the M-BUS-1 data exchange protocol with LoRaWAN network.
In fields consisting of several bytes, the little-endian byte order is used
CONVERTER M-BUS-1 TRANSMITS THE FOLLOWING TYPES OF PACKETS
1. Packet with current readings from connected heat meter, sent regularly or on request
Size in bytes Field description Data type
1 byte Packet type, this packet == 1 uint8
1 byte Battery level, % uint8
1 byte Values of basic settings (bit field) uint8
4 bytes Meter secondary address uint32
4 bytes Time of readings in this packet (unixtime UTC), by the
internal clock of the converter uint32
4 bytes The amount of thermal energy consumed, Wh uint32
4 bytes Total volume of coolant, l uint32
4 bytes Operating time, h uint32
2 bytes Current flow temperature ⁰С*100 uint16
2 bytes Current temperature in the return line ⁰С *100 uint16
2 bytes Current flow of coolant, l/h uint16
The converter has internal clock and calendar; time and date is factory set. When sending
a packet with the current readings, the device uses the data taken at the nearest time, which is
multiple to the interval, set by the switches:
• 1 hour period: the readings of the beginning of the current hour are sent;
• 6 hours period: 00:00, 06:00, 12:00, 18:00 readings are sent;
• 12 hours period: 00:00, 12:00 readings are sent;
• 24 hours period: the readings of 00:00 of the current day are sent.
When transmitting on request the readings are taken in that moment.
A package of this type is transmitted separately for each connected meter. For example,
if 5 metering devices are connected to the converter, 5 packets will be transferred to the next
connection.