Communication issue on raspberry Pi with S7 PLC

General
1

Hello everybody

I have the following problems:

I have installed Node Red on my Windows Cumouter and created the program here
I connected the controller, set the S7 Node and MQTT parameters and everything worked at once
Now further I have the identical code running on my Raspberry Pi but I get no connection with the s7-300

Ip address of the s7 is 192.168.0.1
eth0 from the pi has 192.168.0.50/24
Wlan from Pi has 192,168,43,81/24

Does anyone have any experience with this mistake?

I have looked at the Port with the command 'netstat' once. Is this Node Red running three times on 1880? Ist this the Failure? When yes how can i stop this?

When I compare the ports on my PC I don't see port 1880! :-S

The latest version of Rasbian is installed on the Raspberry Pi "Rasbian Buster 2020-02-13"

I hope You can Help me.

IMG_20200311_223008
IMG_20200311_2230082016×1512 1.21 MB

flows (5).json (20.1 KB)

2

Hi,
sorry for my late response. It seems to be a network issue. Did you try pinging the PLC from your RPI?

3

Check also if you for some reason have several NR running, use command 'ps aux' in Linux

4

Hi folks

Thanks for your help. Didn't solve the problem but I was able to work around it with a simple switch (Netgear Prosafe GS10s).

Now I have the same problem again with a RFID portal reader. As long as I connect through a switch everything works fine.
If I connect directly and do a static IP I can't ping over eth0. No PLC no portal reader.

I have tried various IP setup and cables and everything else. Everything did not work.

Do you have any idea?

5

If you are trying connect 1:1 then a) both ends need to be configured with static addresses within the same segment. But not the same address. And b) you may need a crossover Ethernet cable as basic devices don’t do auto-crossover.

6

Hi dceejay

Thank you for the quick answer. The IP are RPI=192.168.0.249/24 und Portalreader=192.168.0.250/24

I`ll try with the crossover cable. Didn't think that a switch would do the crossover automatically :shushing_face: :hear_no_evil:

Could it be that the RPI 3+ did this on its own? In an old application with the RPI3+ and a PLC it worked without a switch with a standard ethernet cable. I use the same cable now on the Pi 4.

Thank you in advanced :+1: :+1:

7

Hi dceejay

I have tried using a crossover adapter and I still have the same problem.

Ip address of the Portalreader is 192.168.0.250/24
eth0 from the pi has 192.168.0.36/24
Wlan from Pi has 192.168.0.42/24

The wlan network and the lan network wer the Eth0 form the pi is connected ist the same.

Ip Scann = there are no conflicts.

Is there a Setting in the Pi i forgot?

8

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.