Hello @lessmann,
the limit of how many devices can be connected to one RS485 line comes from the RS485 transceiver (the chip on the RS485 output) and on our PLCs it is 32. But be aware, that this is just a theoretical limit and the real limit depends on the current situation.

Second limit of the RS485 is the speed of the communication. Since RS485 is a half-duplex type of communication (master can speak only to one slave at a time), the more devices you have the lower speed of updates you will have.

If you have PLC with more RS485 ports, you can split the extensions into groups.

Best regards,
Martin

Dear Unipi support team,

Is there a way to make the SSCP to SQL Bridge more robust, for example, so that it is not necessary to restart it manually after every solution deployment or PLC restart?

Many thanks in advance and kind regards.

@Martin-Kudláček do you know a good way to eliminate these false positives? Maybe an extra circuit before the input of the Unipi 1.1?

@lyngaas
Hello,
unfortunately, booting our OS images from an SD card on Axon is not supported.

Best regards,
Kryštof Černý

Hello @FabioIT,
the Node-RED image is defacto a Raspberry Pi OS. You can proceed with any general tutorial for adding the desktop environment, which you can find on the offical Raspberry Pi OS webpage.

Hi everyone,

In the current version of Mervis OS 2.4.2.4, writes to the card already occur at least, according to the set interval for storing retain variables.
For a similar reason, the history is newly stored in RAM (data is lost after the power is disconnected or restarted), which does not matter in combination with the cloud-based Mervis DB.

If you disable writes to the internal storage (SD card), there are two possibilities of what can happen (depending on how you disable the writes):

Mervis RT always unlocks the storage when writing retain variables, writes and locks the storage again for writing (basically the same behavior as now) Storage will be permanently locked and retain variables will not be writable. Likewise, it will not be possible to upload a new assembly (program) from Mervis IDE.

In general, I recommend purchasing an SLC card with a longer lifespan and resistance to random power outages, etc., for the operation of the controller.
You can read more about this issue in this article.

Best regards,
Antonin, Unipi

Hello @Martin-Kudláček ,

I have been able to solve the 1-10v dimming problem.
It was a bit of a puzzle, but in the end it went well.
I have created an extra node to a div.
I solved the EQ problem by adding a LT compare function so that when the counter reaches 0 it automatically becomes 1 again. When I now click the dimmer button on the hmi, the LED lamp gradually rises and stops when I release it. I press it back in, it goes down again, etc.
The LED lamp driver uses about 2 milliamps so i can connect enough drivers for the room lighting.
I am very happy with this solution and would like to thank you for your support.

Many regards John-paul

main.png dimmer#5.png dimmer#4.png dimmer#3.png dimmer#2.png dimmer#1.png

Hallo
Ich habe bei mir ein unipi 1.1 bekomme auch Information von mervis zurück ,jetzt meine Frage ,wieviel Modbus Knoten kann ich in node red einbringen.
Ich habe 3 Stück, bei den die Verbindung unterbricht
Was mache ich falsch

Dankeschön für eure Antwort

Udo

Hello @HVAC-Arthus

First, I recommend downloading and installing the latest Mervis IDE and Mervis OS available here: https://kb.unipi.technology/en:files:software

Then open the project in a new IDE and save to convert the project to the new version. Before converting to the new version, we recommend that you always create a project archive with a suitable name.

If you use the RaspberryPi 4 computing module for Unipi 1.1 / Lite, this should also solve your problem, as support for these computing modules was added only in the last version. With my RaspberryPi 4 and Mervis v2.4.0 your project works.

@AVsetula I'm aware of this guide and about the OW_off_1 switch. The problem is, that it does not solve the problem in my case.
As I wrote before I tried to set OW_off_1 to true and then back to false, but all the temperature sensors kept showing 0 ˚C.
I haven't found any software way how to "restart" the 1W to working state. The only thing which works is restarting whole Neuron by cutting off the power.

If you have any other ideas, I'll appreciate them.

Is Evok 2.4.24 fully compatible with Bullseye?

I have one RPI with headless Bullseye and on that one everything seems to work.

I have another RPI with Bullseye and Lightdm on top and on that one relay state change with JSON POST does not work.

Example:

POST http://localhost:8080/json/relay/1
Content-Type: application/json

{
"value": "1"
}

Result:

HTTP/1.1 200 OK
Content-Length: 44
Access-Control-Allow-Methods: POST, GET, OPTIONS
Server: TornadoServer/4.5.3
Date: Wed, 15 Feb 2023 09:48:09 GMT
Access-Control-Allow-Origin: *
Access-Control-Allow-Headers: x-requested-with
Content-Type: application/json; charset=UTF-8

{
"status": "success",
"data": {
"result": 0
}
}

The result is "0" and the relay is not switching.

Any idea?

Best regards,

Noël Vaes

Hello @Bart-Delaere,
unfortunately there is no definitive answer. The 1-Wire bus is technically able to connect huge amount of devices, but reality depends on cable length, quality, noise from the environment etc, so this may be trial and error for users that do not install it daily.

Unipi used to sell a hub/splitter, which we do not offer anymore.

Sometimes, a surge can occur in the environment, which can take down the whole bus. Unipi units (except Unipi 1/Lite) have an option to restart the bus (the bus is not restarted during normal system reboot), you can look in the Modbus table of your unit if you wish to implement it.