Connect a Nitra CMV Valve to Do-more PLC via Explicit Ethernet/IP from AutomationDirect

Before we begin you must have a Domore or BRX CPU that is compatible with Ethernet Ip messaging. SO Do more Designer software and PLC firmware must be version 1.4 or higher and the CPU that you are using must have an on board Ethernet port. This will not work over an Ecom module or over the Ecom POM module for BRX. This is the required information to setup the Valve for Explicit Ethernet Ip communication. So the input data is what you are reading from the Valve and the output data is what we are writing to the valve. The input data consists of a single byte which is 8 bits. The output data consists of 2 bytes or 16 bits. 1 bit for every solenoid possible on the valve. To set up the CMV valve for Ethernet configuration, you will need to obtain the EIP configuration tool from our website. So, Navigate to our website and under downloads select software. Find the EIP software download and install into your PC . Once installed open up the EIP configuration tool and then select “Scan for devices. Once you see your OEM Device. Select and put in the Ip Address you need for your system. I am going to use the following Ip address for this example. Now get connected to your Do more plc and in software let’s begin with creating an Ethernet/Ip Explicit Client. Now this step is not mandatory, you could use the generic Ethernet IP client, but If you setup a client specific for this valve it will allow for a timeout and retry setting for this valve only. To communicate with your valve, you will need to insert two EIPMSG instructions into your code. One for the Input data and one for the output data. Lets begin with the Input data. Once you Place the EIPMSG into our code. Select the Ethernet Ip device we created. Next either type in you ip address or use a variable for your IP. The TCP port for this device will be 44818. The Path data comes from the configuration we saw before. Type 4 for your class, 101 for your instance, 3 for your Use Attribute, and for you Specific Service Select that should remain the default of Get Attribute. I am going to set this at the continuous interval of 100 millisecond. Here the RES start is where the data read from the CMV valve is stored in the DO more PLC. The Response Length in bytes must be a variable and it will store the actual number of bytes that is returned from the Get attribute. The Response Max length in bytes will be 1, as we are only reading in 1 byte or 8 bits of data. So that takes care of the read Now let’s set up the write. Place another EIPMSG message Instruction in your code. Use the same device, Ip address, and TCP port as before. As before take the output data and transcribe that in the path. When we get to service that will need to be changed to Set attribute I will set the Instruction to write to the valve block at a continuous interval of 100 milli seconds. The REQuest Start is the data we will be wrtting to the valve. I have selected V5. The number of bytes we are sending is 2. Be aware that when wirting to this valve with Explicit unconnected messaging, that the valve will stay at the last state if communications is lost to the valve. Here we will place a ST1 contact in front of each of the instructions as I want these to always read and write. Now write this to the PLC. Now to verify we are actually writing to the device. From the Data view let’s verify that we can turn on the valves. So we are writing V5 to the Valve and from this table we see bit 0 turns on valve 1. So let’s put V5:0 into data view, turn on the edit feature and double click On. The 1st solenoid should turn on. You can select the V5:0 and while holding down the control button hit enter multiple times and this will fill out the rest of the word into the data view. We can also view the status of the read block by placing V0 into Data View. If you need any help with using an Automation Direct device please contact Automation Direct’s free, award winning Technical support team during regular business hours – they will be happy to help. And don’t forget the forums. There are lots of folks there that love to share their years of experience. Just don’t post questions directed at Automation Direct’s Technical support staff there, they do not monitor the forums on a regular basis.