AB Micrologix 1200 - Connecting & Acquire Data using .net

Question

I am .net programmer and Know Little bit about PLC & HMI.

I have an upcoming project which required to read data from Allen-Bradley PLC Micrologix 1200. I searched through Online Available Content about connecting PLC to Computer for reading the data from PLC, found one way i.e. MODBUS.

Can you help me regarding :

1. What will be the easiest way of connecting to AB Micrologix 1200.
2. One COM Port on Micrologix 1200 is already connected to HMI and there is no another port available, what will be the way to accomplish connection?
3. Which Library is best suitable for connecting to AB PLC.

Please guide.

Thanks.

Answer 1

I'm not an expert in Allen-Bradley, but it seems that this PLC model has Modbus RTU, if your HMI is using this same network, you can possibly join it with your supervisory system, as long as you take care with the network setup, Adresses...

Otherwise, you could search for some expansion module to include one more network port.

I think Modbus RTU would be one of the easiest options for you, there are tons of examples on the internet. An exception will be if data volume and speed are critical, in which case an ethernet-based network or something else would be better.

I've tried some examples from Mesta-Automation, take a look at this article, I think it might be a good starting point for you.