CIP Program for Allan Bradley PLC
I am looking for a PLC program for a Tri-clover CIP set ( model 48-2789 ). It is a 3 tank CIP set. Unfortunately when we purchased the system the PLC was ripped out and the programs missing. The system was a faitly common design ( drawing No. 91-1320-1) for both water and silicone based CIP sets in the early 90's. It is equipped with an Allan-Bradley PLC SLC-5/02 with 10 ports. I realise this is a longshot but I had to give it a try before I pay somebody to write me a customised program.
The first place I would start is with the OEM. They should still have the program on file and this will be your best bet to get a working program that doesn't require a lot of troubelshooting. Many OEM's will provide copies of this at no charge. Ask for tech support as they're more interested in solving your problem than making a sale.
Even if someone has the same model CIP as the one you purchased, there may have been program changes over the years or additional sensors added that would cause a problem if you loaded the program into your machine.
We have a couple of 3 tank systems (different manufacturer) that I imagine are operating in much the same way. I'd be happy to discuss this further if you don't have any success through the OEM.
As Brian has said, go back to the OEM. However, even if you did get a programme out of them, it is probable that it won't do exactly what you need it to do. In this case, you will have to get someone in to change it anyway, to fully integrate it into the plant to be cleaned.
There is no standard method of writing ladder logic, and in some ways you may be better off starting from scratch with a good programmer. One major problem seems to be finding someone who actually understands the process, and interaction of CIP with the rest of the plant, not just merely following a set of written instructions. The good guys will actually ask a lot of what if's as they write the code. The less experienced guys will merely write stuff to open this valve, close that valve etc in a prescribed order without thinking how it will might, for example, cause pressure shocks, valve lock ups.
The other problem is that you need to have people who can wire up correctly and then validate all the plant items. Some programmers can do this, but again, they seem to be rather like hens teeth, to a large extent I suspect because they tend to be specialists and prefer to specialise in code writing. People who are good at doing hardware tend not to be any good at software.
You will need to absolutely clear in your own mind how you want the plant to operate, and what interlocks etc you want incorporated before you get any code written or amended.
I can help out with CIP sequence design if you want.