LoRa Project for Actuators

Applications
1

I am carrying out a project based on Lora. I currently have the 7240 RAK brand gateway (16 channels) and 7431 RAK brand nodes as well (they are LoRa to Rs485 converters). The devices connected to the node are actuators that use Rs485 communication, that is why the previous node has been used.

These actuators receive a 22-byte wait command for operation, and this data must be updated every 10 seconds.

After different tests, we want to send this information to a total of more than 40 nodes, but with 12 nodes we already have problems and information is lost, since we see that it does not reach all the nodes correctly. Together with the LoRa sending frame we have a frame of the size of 28 bytes (6 from LoRa and 22 from the RS485 equipment).

We know that LoRa technology is preferably intended for sensors, not actuators. In fact, we find that in almost all gateways on the market, the majority of channels are intended for Uplinks and not for Downlinks. LoRa communication was ideal for our project, due to the coverage distance, bit/s transmission and elements necessary for communication.

However, I am running into the problem of information being lost. This are my questions:

  1. Is LoRaWan really what my project needs?

  2. Is there a LoRa system designed for actuators and not so much for sensors?

  3. Are there any gateways with Downlinks priority?

  4. Is the data size sent by Downlinks too large?

I would greatly appreciate your help.

2

Every 10 seconds, across 40 nodes (and you’ve noted hitting problems at 12) - I would say no. If someone put a gun to my head I could come up with a few suggestions, but rapid and reliable/confirmed downlinks is not LoRaWAN’s forte.

1 Like
3

Thanks for your reply!

4

What is your current use case?
Why you have to turn on/off the sctuators every 10s?

5

The actuator is an RS485 LCD Panel. It is permanently working and it needs to refresh their information every 10 seconds.

1 Like
6

Then the nodes only need to send uplinks (not downlink) to the gateway right?

40 nodes to send uplink every 10s is still acceptable with some loss.

However, I think it is better to send every 1-5 minutes.
And the node can send uplink instantly if there are data changes.

For LoRaWAN, it is not advisable to send downlink every 10s.
Should only do if there are data changes to minimize the downlink.

7

Exactly, nodes only need to send uplinks to the gateway to verify that the message has been received and to send the LCD panel status (live or not alive).

Thanks for all your cooperation!