eeproms excellent answer notwithstanding, if you don't know or have nothing installed now (unbelievable as that is), then as with VFDs, my advice is to go with a brand that will provide you with excellent support IN YOUR AREA. Rockwell for N. America and Siemens everywhere else are good basic choices, but that doesn't rule out others, there are good suppliers out there for every brand. I would ask around with other users IN YOUR AREA as to who they get top quality support from and go with that.
If you are an OEM sending equipment to a plant somewhere else and your customer has not given you a preference, it's either because they are completely backward or they have no regard for their investment in automation. It's not about hardware, everyone makes good hardware or they would be out of business. It's about support and training, and that usually costs MORE than the hardware. A few basic questions to your customer may be in order here.
But if that gets you nowhere, most bottling line equipment OEMs I am familiar with typically go the Rockwell / Siemens route depending on the end user's destination, simply because of the ubiquitous nature of the available support from those two. But having recently come from a Siemens integrator in California and seeing a lot of bottling line equipment for the wine industry coming in from Italy and other EU countries, I can tell you that most of those people selected Siemens because of the support they were used to in the EU and got a rude awakening when their equipment arrived in Northern California, where we were virtually the only source for quality support. Even the Siemens direct people were few and far between, the OEMs frequently had to fly people in from Italy to get systems up and running. Had they chosen Rockwell, they would have been beating people off with a stick who would want to help them. So bottom line, that's what counts, what is available AT THE LOCATION.
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