What I Thought the Problem Was
If you've ever sent an RFQ with finder relay 24vdc and watched five quotes land in your inbox before lunch, you know how tempting it is to sort by price and send the PO. That was my routine for the first few years in procurement.
I've managed purchasing at a 40-person control panel builder for the past six years. We buy about $180,000 a year in electrical components, including relays, contactors, PLCs, and other industrial control parts. The budget pressure is real, and I used to think my job was to get the lowest unit price on every line item. I was good at it, too.
Then, in 2023, one of those price-driven relay purchases failed at a customer's site. The final bill was more than 200 times the unit price of the relay. That ratio made me question how I source Finder relays, and it's why I now keep a cost log rather than just a purchase order file.
I'm not an application engineer, so I can't speak to every detail in a datasheet. What I can tell you from a procurement perspective is where the money actually disappears.
The Part Number Trap
After that failure, I audited several years of relay orders. The pattern was uncomfortable. I had been comparing quotes based on loose descriptions like finder relay 24vdc without confirming the full manufacturer part number. That sounds specific. It isn't.
Depending on the series, a 24 VDC Finder relay can have different numbers of contact sets, terminal layouts, coil consumption, contact material, and approval markings. Some relays are built for basic signal switching. Others use force-guided contacts so a safety circuit can monitor their position. They all appear in a search for a 24 VDC relay. They are not all interchangeable.
I found one order where we saved $47 by choosing the lowest quote for what the supplier described as an equivalent model. The parts arrived on a Friday afternoon and didn't fit the sockets used in our panel. We spent $312 on expedited shipping and four hours of overtime to fix it before Monday. A $47 saving turned into a roughly $500 mistake, and we were lucky the assemblers caught it before the panels left our shop.
I don't mean to imply that every equivalent model is bad. The point is that the substitution decision belongs to engineering, not to whoever is comparing quotes on a Friday afternoon. I had the process backwards: I let the price decide what we bought and then asked engineering to make it work.
The Problems a Quote Hides
By 2024 I had started asking suppliers for two more things before placing an order: batch traceability and product documentation. That simple change was surprisingly revealing.
A supplier can quote an excellent price, confirm stock, and still not be able to tell you which production lot that stock came from. That seems harmless until a relay fails and you need to know whether other customers received relays from the same batch. Without lot records, you can't do containment, and containment uncertainty becomes a cost. (Mental note: ask about date codes before ordering, not after the problem appears.)
Documentation matters even more when you build for OEM customers. On a safety PLC OEM project, components in safety-related circuits need to be identifiable, approved, and documented. If a supplier cannot provide lot numbers, date codes, and relevant declarations, the small price advantage disappears the first time a customer asks for proof.
I'm not a compliance specialist, so this isn't regulatory advice. From a purchasing perspective, though, documentation is part of the deliverable. Treat it as one.
The $43 Relay That Cost Us $8,700
The failure that changed my process began as a relay in one of our control panels. It stopped energizing after about a year at a customer's plant, and the customer's production line couldn't start until the panel was repaired.
The relay itself had cost us $43. That price was not the real cost.
When we added up the field service call, after-hours labour, travel, and the downtime credit we agreed to under warranty, the total came to about $8,700. I checked the purchase order history. We had saved roughly $600 on that batch by accepting a substitute model instead of the exact Finder Relay part engineering had specified. A $600 saving was erased more than fourteen times over in a single afternoon.
The money was painful. The trust cost was worse. Engineering wanted to know why purchasing had accepted a substitute without flagging it. The service manager wanted to know why we hadn't recorded the batch information. I didn't have good answers, and rebuilding that trust took months.
Not every mistake is that dramatic. In Q4 2024, we accepted a low-price quote for 120 relays, and six of them failed basic incoming inspection. The remaining units had to be tested manually before production would use them. We saved $93 on that order and spent roughly $1,400 in extra testing time and rescheduling. Same pattern, smaller numbers.
What I Do Now
I still send out RFQs and compare quotes. I just don't let unit price make the decision by itself.
First, we define what we're actually buying before we talk to suppliers. We always did this for PLC sourcing, where the controls engineers specify I/O, communication protocols, and environmental conditions. Relays and contactors got vague descriptions, which makes no sense in hindsight. Now engineering confirms the exact full Finder Relay part number before an RFQ goes out.
For contactors, we use the same logic and go through what amounts to a contactor specification guide: coil voltage, contact ratings, utilization category, auxiliary contacts, and approvals. If you don't specify those details, you're not comparing contactors. You're comparing prices for things that merely look similar.
Second, documentation and traceability requirements go directly into the RFQ. An acceptable relay quote now states the full part number, available lot and date code information, and relevant declarations. Price and lead time are still there, but they're not the only fields. If a supplier can't answer those questions, it's a red flag. That doesn't always mean the parts are bad. It means the supplier won't be much help when a problem appears later.
Third, I evaluate total cost rather than quote price. Unit price is one input. Documentation quality, lead-time reliability, and how a supplier behaves when something fails are also inputs. Basically, I'm buying from suppliers I can trust, not just parts at the lowest number.
So What Should You Be Comparing?
If your RFQ still says 100 pieces, finder relay 24vdc, best price, you are not comparing the same product from different suppliers. Add the full part number, the documentation requirements, and the traceability requirements. The cheapest quote may then look different.
Last year a new supplier quoted about 15% below our regular source. The spreadsheet said we would save roughly $1,100 a year. My gut said to slow down. They couldn't confirm lot traceability, and the certificate copies never arrived after two follow-ups. I passed. It wasn't a purely data-driven decision, and I'm okay with that.
Bottom line: unit price is where the cost starts, not where it ends. After six years of purchase orders and failure reports, I would rather pay a little more for a relay that comes with clear documentation, traceable stock, and a supplier who understands what they're selling. The $43 relay taught me that lesson the hard way.
So next time you receive a row of quotes, feel free to sort by price. Just ask one more question before you send the PO: if this part fails in 18 months, what will it actually cost? From my experience, the answer will be a lot more than the difference between the quotes.
