Modernizing Extinct Process Controls
I started working in the industrial automation industry in 1988. The newest Allen-Bradley PLC at that time was the PLC5. I began doing PLC2 to PLC5 conversions almost immediately. The conversions went well.
In 1995 I had an opportunity to do two PLC3 to PLC5 conversions. Since my other conversions had gone well I had full confidence that this would go well also. I sent out the PLC3 programs to be converted. The going price was $2500 per program. I thought that would save me a lot of typing and therefore worth the price. The PLC5 program I got back was so full of translation errors that I spent the next several weeks doing a rung by rung cleanup. I went back to the people that had done the conversion and asked for my money back. Nope, sorry, “as is” was the reply.
Now I needed to test it in a real application. It wasn’t long until a colleague of mine was doing a PLC3 conversion. I asked if he would let me convert the program for him. He agreed and emailed me the program. I ran it through my utility and sent it back to him within the hour. He was amazed. During start-up he found only one translation error which he was able to reprogram very quickly. (Incidentally, only three programming errors were ever found in that original conversion utility).
One day in 2002 I got a call and was asked if I could do a Modicon to ControlLogix conversion. Up to this point I had only written Allen-Bradley to Allen-Bradley conversion utilities. I told the guy that I could but it would take two to three months to write the utility. He told me that they were in a hurry and would do the conversion by hand. I thanked him and started working on a conversion utility anyway. Three months later my conversion utility was finished. I assumed that they had long since finished their manual conversion and had done the start-up. I called to see if they would look over the converted program that my utility created to see how well it had converted. I was surprised to find out that they had been converting code manually this whole time and were only about half of the way through (it was a very large program). When they showed the end-customer the program that my utility created, the end-customer requested that they use my converted program and not the one they had spent months typing in by hand.
I had been asked many times if I would create a GE to ControlLogix utility. So in 2005 I started working on a GE to ControlLogix utility. I was about three-fourths of the way done in 2006 when I got an email wanting to know if I could do a GE conversion. I replied that I could. They were expecting just the program to be converted but when I delivered the ControlLogix program to them with program, data table, and documentation they were very pleased.
In early 2007 I decided to make my own conversion utilities and provide PLC conversion services to the public via the internet.