Modbus scan_interval: too slow option Serial RS485 Now with video

Feature Requests
1

Hi.

Posted here Modbus scan_interval: too slow option Serial RS485 · Issue #33359 · home-assistant/core · GitHub

I have modbus controller for my low power toggle switches in my house. But the 1 second option is just way too slow. Is it possible to make it scan down to ms instead. I have testet it in Node-red but the setup is difficult when more then one device is connected to the modbus. In node red it has no problem with scanning in 5ms. I want to make sure my 5*(32) modbus inputs are scanned every 50ms to make the toggle work correctly.

Systemsundhed

arch armv7l
dev false
docker true
hassio true
os_name Linux
os_version 5.4.20-sunxi
python_version 3.7.7
timezone UTC
version 0.107.6
virtualenv false

Lovelace

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I use serial connection.

Best regards
Nicklas
Denmark

2

Hi Nicklas,

I ran into the same issue. All my light switches are connected to a modbus PLC, and scanning the inputs directly with HA is too slow. I think the scan interval limitation is about a second.

What I did is use Modbridge made by @mhemeryck to scan the PLC and send out which switch has been activated through MQTT to my HA instance (with the broker installed on HA). This works very smoothly, my switches are read out instantly.

Hope this helps,

Tom

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