If you're a small or medium-sized integrator or manufacturer considering a PLC for your next project, the Siemens S7-1200 offers the best total cost of ownership (TCO) in its class. I'm not saying this because I work for Siemens. I'm saying this because over the past 6 years of managing a purchasing budget for a 50-person automation firm, I've analyzed $180,000 in cumulative spending on PLC hardware, programming software, and support contracts. The S7-1200 consistently beats competitors on the metrics that matter to a buyer: upfront cost, ecosystem lock-in, and hidden long-term expenses.
In Q2 2024, I ran a formal comparison between the S7-1200 and a comparably specced Rockwell Micro800 series for a small packaging line upgrade. The Siemens path saved us $1,450 in the first year alone, mostly due to the TIA Portal's superior debugging tools reducing programming hours. That's not a marketing claim; it's the figure I recorded in our cost tracking system.
The base hardware price for the S7-1200 (CPU 1212C) is competitive, but the real savings come from a few less obvious places. When I compared costs across four vendors for a recent project, Vendor A quoted $1,200 for the S7-1200 CPU and basic I/O modules. Vendor B quoted $1,050 for a Rockwell Micro850. I almost went with B until I calculated TCO: Vendor B charged $380 for a basic communication module that's built-in on the Siemens, and $220 for their version of TIA Portal's starter package. Total after year one: Siemens $1,580, Rockwell $1,650. That's a 4.4% difference hidden in the fine print.
From my perspective, the most overlooked cost driver in small PLC projects is the opportunity cost of delayed troubleshooting. The S7-1200's online diagnostics, which are far more detailed than what you get with entry-level competitors, have saved me countless hours on commissioning.
I can't stress this enough: when I was starting out at a smaller firm, the vendors who treated my $200 orders seriously are the ones I still use for $20,000 orders. Siemens distributors, in my experience, are generally good about this. I once placed an order for just two S7-1200 CPUs for a pilot project. The distributor's technical rep spent 20 minutes on the phone with me making sure I had the right expansion modules. That's not a policy—it's a cultural attitude.
Small doesn't mean unimportant—it means potential. The way I see it, a vendor that "doesn't have time" for small customers is a vendor that doesn't understand how real-world procurement works. Today's pilot project is next year's production line standard.
Honestly, I'm not sure why some automation engineers jump to the S7-1500 for projects where the 1200 would do. My best guess is it's a combination of habit and perceived performance headroom. But for simple machine control, process monitoring, or small-scale manufacturing, the 1200 is often over-engineered in a good way.
There are exceptions. If you need high-speed motion control with multiple axes or distributed safety over PROFIsafe at scale, the S7-1500 family is the better choice. Also, if your maintenance staff is deeply trained on Rockwell's Logix platform, the retraining costs could outweigh the hardware savings. I've seen that happen—a $1,200 redo when a team wasn't comfortable with the new environment.
The S7-1200 also doesn't support the entire TIA Portal feature set. Some advanced functions, like software-based controllers or specific cloud connectivity modules, require the 1500. For 80% of small to mid-size applications though? The 1200 is absolutely the right move from a buyer's perspective.
If you're building a new system and your budget is tight, start your evaluation with the Siemens S7-1200. The global PLC market share data from 2023 (source: ARC Advisory Group) shows Siemens holding 16% of the market, just behind Rockwell. But for small-scale applications, the real-world cost advantages are more significant than market share suggests. The key is to think in total cost of ownership, not just sticker price. And when a vendor takes your small order seriously—that's a sign they'll be a good partner when your business grows.