Look, I'm going to say something that might sound counterintuitive if you're responsible for a budget: I stopped buying the cheapest Siemens PLC modules I could find. And the result? My overall procurement costs dropped by about 17% over three years.
Here's the thing: when you're managing a B2B automation budget, the unit price on a purchase order is only the beginning. I learned this the hard way after tracking roughly $180,000 in cumulative spending on automation components over six years. The pattern was undeniable.
In my opinion, the obsession with the lowest upfront price is the single biggest cost driver in industrial procurement. Not the premium products—the cheap ones.
I assumed 'same specifications' meant identical results across vendors. Didn't verify. Turned out each had slightly different interpretations of what 'equivalent' meant for our Siemens S7-1200 setup. One vendor's 'compatible' module had a different firmware revision that took our engineer two days to troubleshoot. That two days cost us more in labor than the savings on the module itself.
That $200 savings turned into a $1,500 problem when the module failed during a production test and we had to rush-ship a replacement.
After tracking 47 orders over 6 years in our procurement system, I found that 62% of our 'budget overruns' came from the modules that were initially the cheapest. We implemented a policy requiring TCO analysis for any quote more than 15% below the market average, and we cut overruns by about 40%.
Here's where the money actually goes:
For reference, when comparing quotes for a recent order of 10 Siemens S7-1200 CPUs, a budget vendor quoted $3,800. A premium distributor quoted $4,400. The difference: $600. But the budget vendor charged $180 for shipping, $75 for a 'compatibility verification' certificate, and had a 3-week lead time. The premium vendor included free shipping, a 48-hour lead time, and a direct support line. The total cost of ownership favored the premium option by about $350 once we factored in the cost of waiting three weeks and the potential for a production delay.
I can already hear the counterargument: 'But my budget is fixed. I can't afford the premium option.'
Fair point. This worked for us, but our situation was a mid-size B2B company with predictable ordering patterns. If you're a startup or a seasonal business with tight cash flow, the calculus might be different. I can only speak to our context.
But here's what I'd push back on: if your budget is tight, can you afford the risk of a failure? That single downtime event could cost you multiples of the savings you made on the purchase order. In our industry, production downtime costs roughly $1,000–$5,000 per hour depending on the line. A cheap module that fails can wipe out a year's worth of 'savings' in one afternoon.
To some extent, I'm also biased by our experience. We had a bad run with a particular low-cost vendor two years ago, and it made me skeptical. Your mileage may vary if you find a reliable budget supplier with good support.
I don't have hard data on industry-wide failure rates for PLC modules, but based on our 6 years of orders, my sense is that quality issues affect somewhere between 8% and 12% of first deliveries from ultra-low-cost vendors. For mid-tier and premium suppliers, that number drops to about 3–5%.
The way I see it, you're paying for predictability. The premium isn't for a fancier box—it's for the confidence that it will work when you plug it in, and that if it doesn't, someone will pick up the phone.
Personally, I'd rather pay 15% more for 90% fewer surprises. That trade-off has worked well for us.
If you've ever had a delivery arrive and not work, you know that sinking feeling. The cheap module isn't cheap anymore once you're paying for the repair.