Beckhoff PLC integration

[Stan1979]

Hi,

I do not use Arduino, I'm running an industrial Beckhoff PLC.
Programming isn't a problem, I will only need to buy an analog input for my PLC.

Can you tell what I need to install your system to my PLC?
Does it have an analog output or similar?

[Christian_Bylund]

Hello Stan,

There is a couple of different ways to connect an Arduino to a PLC. I am a bit rusty on my ladder programming but I can definitely help with the Arduino side of things.

I think we can have two ways of interfacing to the PLC depending on its capabilities.

• An analogue input interface, the Arduino can output 0-5V with an RC-Filter. (See this video)

• If you have any way of receiving a value from RS232 this would be the easiest.

I was just looking for a DIN rail mount for Arduino and there seems to be plenty of suitable options.

[Stan1979]

Isn't it possible to run the lambda sensor without the Arduino?

RS232 could be an option, there is a card and it isn't to expensive :)
Any analog signal is ok.

[Christian_Bylund]

Isn't it possible to run the lambda sensor without the Arduino?

Unfortunately not since it is a Wideband sensor it requires some control circuitry to function. We offer the complete kit for 150 EUR. There are other dedicated options like the Innovate LC-2 for 180 USD, but in my opinion you loose the level of customisability offered by the Lambda Shield and Arduino solution. Basically you can program it to behave and work the way you need it to.

RS232 could be an option, there is a card and it isn't to expensive :)
Any analog signal is ok.

Analog output as you have seen is no problem, all you need is a capacitor and a resistor that you can easily fit directly on the wiring. Perhaps it would be best option. Not sure if the UART output matches Industrial RS232 standards after reading up on it.

What model of PLC do you use?
Do you have the possibility to use a 12V power supply? - Then you can power both the Arduino and Lambda Shield from the same source and get a stable 0-5V output.

[Stan1979]

I'm running a Beckhoff cx1020.

12Vdc isn't a problem, 5v 12v 24v, whatever you want.

But I'm not a fan to use another control system next to my PLC.
The Beckhoff is stable as hell and this is the system I choose therefor.

Isn't there another solution?

[Christian_Bylund]

I'm running a Beckhoff cx1020.

12Vdc isn't a problem, 5v 12v 24v, whatever you want.

But I'm not a fan to use another control system next to my PLC.
The Beckhoff is stable as hell and this is the system I choose therefor.

Isn't there another solution?

If you can interface with 5V directly to the Lambda Shield it is probably possible, the minimum is heater control 1 x 5V PWM output as well as 2 x 5V analog inputs for heater regulation and lambda output. Preferably you would also want SPI communication to read the status registers from the lambda controller.