Two years into managing procurement at a 40-person OEM, I did something I'd been putting off: I exported every electrical component order from our accounting system and sorted them by vendor. PLCs, drives, contactors, relays, timers—about 380 line items. I was sure I'd find that we were overpaying for ABB PLCs. What I actually found was worse. We weren't overpaying on the invoice. We were overpaying in the things around the invoice. Shipping. Expedite fees. Software licenses we bought twice. A drive distributor who had great prices on VFDs but couldn't help when the PLC wouldn't talk to them. A contactor supplier who asked for a part number and nothing else.
This isn't a post about getting the lowest price. It's about what six years of tracking our spend taught me about PLC sourcing, drive distributor selection, and contactor suppliers.
The Real Price of a PLC Package
When I first took over sourcing, I compared quotes for three AC500 CPUs. One distributor was $215 cheaper per unit. I almost switched the whole order because of it. Then I added up the rest: a software license, two days of training for our electricians, and freight. The cheaper quote didn't include any of that. By the time we accounted for separate shipping and a nine-day longer lead time, the 'savings' had become a net loss of roughly $380. In exchange, we got a vendor who couldn't answer a basic question about memory allocation.
I'm not an electrical engineer, so I can't speak to every technical detail of CPU cycle times or backplane design. What I can tell you from a procurement perspective is this: the component with the lowest unit price rarely has the lowest total cost. That sounds obvious. It wasn't obvious when I was staring at a spreadsheet showing a $215 difference and my boss was asking why we hadn't bought from the cheaper source.
That was the first time I built a total cost of ownership line. Since then, every quote gets the same treatment:
- Hardware cost
- Software and firmware alignment
- Training or engineering support
- Freight and expedite risk
- Expected lead time vs. our production schedule
That list stopped more bad purchases than any other change we made.
ABB PLC Software: Where Sourcing Gets Complicated
Here's something vendors won't tell you: the word 'available' on a distributor's website doesn't always mean it's in the local warehouse. It can mean it's orderable from the factory with an eight-week lead time. We learned this when a critical CPU showed as 'in stock' online, and the actual confirmed date was 23 days later. Not terrible, but not what we expected.
Another thing that doesn't show up on a quote is software alignment. ABB PLC software—in our case Automation Builder—has version requirements for firmware. If you're buying a CPU from a distributor who doesn't know which firmware revision it will ship with, you're taking on risk. One of our PLCs sat in 'pending configuration' for three weeks because the distributor needed to match the firmware to our existing project. That's not an exotic technical problem.
Here's the thing: PLC sourcing is not just picking a CPU. You're choosing an ecosystem. You're buying into the programming environment, the spare parts chain, and the quality of support when something doesn't communicate. A drive distributor who also carries PLCs is not automatically good at supporting both. We had one who sold us a VFD that worked perfectly, but when I called about the PLC program, the answer was 'we usually sell those as standalone units.' Real talk: if you sell both, you should be able to help with both.
What a Good Drive Distributor Actually Does
I'll be honest—I didn't used to think much about the difference between a parts supplier and a solution supplier. A part number is a part number, right? In practice, the difference showed up in commissioning hours.
A drive-focused distributor with application knowledge can save you from ordering the wrong braking resistor, the wrong fieldbus module, or the wrong cable set. Those are small items on a quote but they become huge when you're on site and the motor won't ramp. The drive distributor we use now asks about the motor nameplate, the application duty cycle, and the PLC output type before they quote. That's rare. It's why they get our business even when their price is not the lowest.
I'm not saying you should overpay for support you don't need. If your team already knows the products, a box mover is fine. But if you're like us—a mid-sized OEM with no dedicated electrical engineer—the person at the distributor who can answer a technical question is worth real money. It took me 90 orders to understand that.
Contactors Are Not a Commodity
Contactors are boring. They're small, they're cheap, and they're easy to replace. For the first few years, I didn't think much about contactor suppliers at all. Then we had a line shutdown that cost about four hours of production. The root cause: a contactor with a coil voltage mismatch and an auxiliary block that wasn't rated for the load. The supplier had asked for the part number. They hadn't asked what we were doing with it.
So here's what to look for in a contactor supplier. Not just a price list. Application knowledge. Do they ask about the load type? According to IEC 60947-4-1, contactors are categorized by utilization categories—AC-3 for squirrel-cage motors, AC-4 for inching and plugging. If your supplier can't tell you why a product rated for AC-3 might not hold up in an AC-4 application, they're a parts counter, not a partner.
What to look for in a contactor supplier, in short:
- Ask if they know the coil voltage requirements and whether a PLC output can drive it directly
- Ask about accessory availability—auxiliary contacts, overload relays, surge suppressors
- Ask for a written delivery date, not 'should be there by Friday.'
That last point applies to everything, but it hurt the most with a contactor because the whole machine was waiting on one tiny part.
What I'd Do Differently Now
After 6 years and about 380 orders, my view is simpler. The best supplier is not the one with the lowest quote. It's the one you can build a specification with. That means they ask questions before they quote, and they can show you what's in stock in writing.
If someone asked me for a sourcing checklist, it would look like this:
- Calculate total cost, not unit cost. Include software, training, freight, expedite fees, and the cost of downtime.
- Buy the ecosystem. If you use ABB PLCs and drives, buy from a distributor who can support both—and who can talk about ABB PLC software without sending you to another department.
- Get stock commitments in writing. Not 'in stock' on a website. A documented date.
- Choose a contactor supplier who asks about your application. That one question prevents the most avoidable failures.
- Keep a second source. It costs a little more until the day your primary supplier has a six-week lead time.
I'd also tell my past self to stop chasing 2% savings on low-value SKUs and focus on the 20% of orders that caused 80% of the headaches. The expensive lesson, repeated many times: a cheap component is only cheap if it works, arrives on time, and doesn't take three phone calls to install.
Everything I'd read about procurement said compare quotes and negotiate hard. In practice, the best savings came from reducing surprises. That's the part I'd go back and explain to myself in 2019.