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The meter reading software issues Modbus query commands to the LoRa
communication gateway (master station), and the LoRa communication gateway
(master station) wirelessly transmits the Modbus query commands to the LoRa
communication gateway (slave station) or smart wireless power meter (slave
station) through LoRa, The Modbus device under the slave station selects to report
data according to the query instruction, and complete a data collection via the
following process:
Slave → Master → Meter reading software
Speed setting:
1. When there is less penetration of solid walls, you can try to select the rate of
3.1K and 5.5K; When there is more penetration of solid walls, you can try to use
the rate of 0.3K for testing. Obstacles will shorten the communication distance,
which is subject to the actual test.
2. This data acquisition scheme is also suitable for DL/T 645 and other similar
Modbus protocol acquisition methods.
3. In order to avoid signal interference, the data of only one slave device can be
collected at the same time, and multiple slave devices are not supported to report
data at the same time.
4. The 485 bus of this LoRa communication gateway supports up to 32 Modbus
devices.
5. The rate level of LoRa has a great influence on the transmission time, so you
should pay attention to the setting of Modbus receiving timeout
