Learn how to connect to a PLC5 through a ControlLogix Gateway using ControlNet.

Video recorded using: Ignition 7.9


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[00:00] In this example we are going to show how to connect to an Allen-Bradley PLC through a Control Logix PLC using ControlNet. This diagram here that I am showing depicts two Control Logix PLCs, so I'm going from one Control Logix to another through ControlNet. So first we're going to start in Ignition and go to our first PLC, the Control Logix and go in through the ENBT module. We're then going to come out through the ControlNet module and down to our second PLC. In order to do this, we have to specify the connection path from PLC one to PLC two, which is effectively the route to get from one PLC to another, like I just demonstrated earlier. If you look down here in the bottom right, there's a connection path that makes this diagram work. Let's go over that connection path in a little more detail. Since I am first going into a Control Logix PLC through the ENBT Module, I need to go out through the backplane, which is why we have a value of one as the first number of our connection path. From the backplane, we need to go out to the ControlNet Module, which is in slot four, so that's how we get our second number of four. Next, we need to specify the ControlNet Port and then the ControlNet Address of the second PLC. So we get a value of two and then a value of 12 from that second PLC. Since that second PLC here is a Control Logix, I need to go through the backplane again to get to the processor. So my next value will be a one to get to the backplane, and then a zero for the slot number that the processor is at. If my second PLC was a PLC five or a SLC instead, we don't need the one or zero at the end. That's only for a Control Logix. One other important thing to note is that the connection path values are separated by commas and only commas. So let's take a look at a real live example in Ignition to see what we're talking about. To start, we need to go to the devices page in the configuration section of the Gateway webpage. We then need to click the create new device link, then need to select the driver for the type of device that we will eventually be connecting to. In other words, PLC number two. In the previous example, we were connecting to a Control Logix through the first PLC which was also a Control Logix. Here though, I'm going to be connecting to a PLC5, so I'm going to select the PLC5 driver. Once that's selected, we then scroll down and hit the next button. We can then give our device a name. I'm going to call mine PLC5 Controlnet. For the Hostname property, we need to specify the IP address of the first device. So the IP address of my Control Logix device is We can then specify the route to our PLC5 device in the connection path property down here. I start with a value of one to go out to the backplane, my ControlNet Module's in slot three, so I then need a value of three. I then need values for the ControlNet port and ControlNet address of the second PLC. The port is two, so I'm going to put a value of two, and the address is 14, so I'm going to put a value of 14. Now in our previous example, we then proceed to put a one and a zero to go to the backplane and then the processor slot number. But in this case, because I'm using a PLC5, I don't need to do that. So that's the end of my connection path. I can then scroll down, and hit the create new device button. You'll notice that once it was able to connect, it quickly browsed the device, and now it's connected to the device through the ControlNet protocol. I can then scroll down and go to my Quick Client under OPC Connections, expand the OPC-UA Server folder here, and find my device with all of my tags in it.

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