PRO license

Good Day to All,
I have 3 question that I would like to get professional help… I’m a newbie here…

  1. Has anyone can share a screenshot of a sample for PRO license ( it is mentioned to have a welcome page in the blynk pricing) , just wanted to have a reference for my project. I will be needing 120 datastream for it.
  2. Has anyone have successfully completed a project using ; Arduino UNO, + W5100 Ethernet Shield + Sim900 using Modbus TCP Master and collect data from existing PLCs and sends data to Blynk cloud? (this leads to my 3rd question :slight_smile: )
  3. Is it possible to sends data to blynk cloud using other hardware such as PLCs?
    Thank You in Advance… Cheers!!!


  1. Tariff plans can be found at the link Pricing | Blynk IoT Platform. Pro plan supports 200 datastreams.
  2. Perhaps users can share such an example.
  3. You can find the list of supported devices here Supported Boards - Blynk Documentation


HI Oleksii,

  1. Thank you for your prompt reply, really appreciate it…
    I have read the pricing plan as mentioned, however, what I requested is a screenshot or running welcome page of the PRO license “if there is any”… this is just to show our client some idea what it look like…
  2. Yes… I was hoping someone can share sample sketch.
  3. Thank you for your clarification… perhaps I need to use those supported boards rather than my existing PLCs.

I’m a bit confused by the choice of Ethernet shield as well as SIM900.
Is this because your Modbus devices have RJ45 connectors, or are they connected to an internal network?
The Uno isn’t a great device to use, as it’s quite limited in its speed, processing power and memory. If you’re a PLC developer then you might think that memory optimisation is second nature, but the libraries you’ll be using are bulky, so more memory would be useful.
The Uno also has only one hardware serial port, so connection to the SIM900 as well as being able to se serial debug messages will require the creation of a SoftwareSerial port (yet another library).

I query/control a solar controller which uses Modbus RS485, and I’ve experimented with a variety of ways to do this, including looking at methods of querying multiple Modbus devices sequentially using the same device. I’ve used either a NodeMCU or ESP32 board for this, with a MAX485 TTL adapter.

Maybe if you shared more detail about the nature of the project and the Modbus setup I’d be able to point you in a better direction as far as your Blynk relay hardware is concerned.


Hi Pete,
Thank you so much for your reply… yes I am a PLC & SCADA SI and now working on how to collect modbus data from the existing workstation to be sent to bylnk cloud…

But after yesterdays test i managed to make it worked and successfully connected to blynk… :sweat_smile: :sweat_smile:

I agree with you for the limited memory capacity of UNO, however this is just a first step and I will move forward on using a much higher memory capacity…

Thank you again for your kind reply… Cheers!!!

jojo :sunglasses:

I also enclosed my test unit here… :point_down:


You can sign up for a PRO trial of 14 days only through the android app. And then check it out on the web.

1 Like

Hi Pete,
Happy new year to you… :smile:
Would appreciate for your professional advice on a hardware to be used in my next project, (sorry for a long silence since our last conversation :blush: I’ve been in a long vacation for the past months…) I will be implementing again a Modbus query to PLC’s but now in a large data, “where in UNO i only requests 12 integer from the Modbus slave”.

Can you indicate which Arduino + Modbus shield or Ethernet shield and communication for these will be through WiFi and sends to blynk cloud…

Love to hear from you soon…


Hi Jojo, I don’t really understand your current hardware setup, so it’s difficult to comment on alternatives.

My Modbus experience is limited to interrogating my Epever solar charge controller, which uses Modbus over RS-485.
As my solar controllers are in a location where a hard-wired connection is impractical, my requirement is for an RS-485 to WiFi system, which upload the results to Blynk via WiFi.

Initially my solution was an RS-485 to TTL adapter connected to a a Wemos D1 Mini pro (the Pro version allows an external WiFi antenna for increased range). Whilst this worked fine, I wanted a solution which occasionally allowed me to run the Epever configuration software across a virtual COM port and my old system didn’t allow this.

My current system uses the Elfin EW-11 RS-485 to WiFi adapter.
I use Node-Red (a visual rules engine and programming environment based on NodeJS) as the gateway between all of my devices and Blynk, do I use a Modbus plug-in for Node-Red to interrogate the Epever controller via the Elfin EW-11 and send the results to Blynk.

I’m guessing that this type of solution won’t work for you, as you seem to be using cellular data to send the results to Blynk, but without more info on what you’re doing with your Uno based system it’s difficult to advise.


Hi Pete,
Thank you so much for a very quick response. :+1: :+1:
Well, for my existing setup, using GSM is a very unstable communication to the internet where cellular signal sometimes broken for about an hour time in that specific area.
I will be trying to implement a Wifi connection instead since the factory has it’s own internet.
My communication to the PLC hardware will stays the same (Modbus TCP/IP).
I am not sure if I would use Mega 2560 + W 5100 and ESP 8266 for sending data to blynk will be a good choice…
Any Thought on this is greatly appreciated.

Hi Oleksii,
Thank you for the information.
Yes, I will be trying to use PRO license soon… :+1: :+1: :+1: :+1: :+1:

It seems unlikely tobe a good choice, you’d probably be better with a board that has native WiFi connectivity such as the ESP8266 or ESP32.
However, I still don’t understand your existing setup, especially why you have both Ethernet and GSM connectivity, so it’s difficult to say more.


Hi Pete,
Sorry I didn’t mention that I will scrap the GSM out and will be using Wifi for these setup.
Below here is architectural schematics of what I am trying to Implement :point_down:



You did, but you haven’t explained the role of the Ethernet shield in either your GSM or WiFi setup. This was my very first comment to you…

And I still don’t know the answer to why you are doing this. Once I understand the ‘why’ bit then I’d probably want to know ‘how’ before I could comment any further.