In my last blog, I railed against a manufacturer that arrayed LEDs horizontally and terminals vertically on a networked I/O product. I said this was counterintuitive and would lead to installation and troubleshooting errors. To refresh your memory, this link shows the installation instruction diagram for a typical module:
Manufacturer X Output Module.
I have a good relationship with that manufacturer's local employees, and they appreciate (or at least they say they do) the feedback I give. I've talked with them in the past about this specific product, and they agreed there was room for improvement.
Last week, my company began building a new electrical panel which used a similar network I/O system from a different manufacturer. I took a good hard look at the device, because it looked very similar to the I/O devices I showed in that previous blog. For this new I/O block, I saw the LEDs and the terminals matched orientation. I thought to myself, "This manufacturer has it right!"
This image shows the LEDs arrayed in a vertical format:
Manufacturer Y Input Module LEDs. This image shows the terminal block for the module, also arrayed vertically:
Manufacturer Y Input Module Terminals.
Note, the terminal numbers printed in a nice contrasting color.
The vice president of engineering of my company burst my excited bubble, asking, "Are you sure about it? The schematics provided by the customer look a bit odd." Darn it, they did. The numbering of the I/O was jumbled. Don't you hate it when bosses make you check the facts when things look so perfectly obvious? In this case, he proved why he's the vice president (although I think he just got lucky).
Shown here is a page from the installation manual for this competitive product:
Manufacturer Y LED Chart. Imagine yourself as an engineer called in to troubleshoot a system with this product. You hit the ground running and are instantly stymied by a system where LEDs indicating inputs and outputs seem to have absolutely no correlation to program numbers. Input 3 is LED 6? Input 6 is LED 4? This can't be right. Can it?
It is. I called the manufacturer to be sure. Their technical support was very careful to point out that the terminal numbers matched the LED numbers, and the LED and I/O numbers shown in the installation manual are correct.
This goes beyond asking for a little commonsense. How about some common courtesy? It's bad enough that they have LEDs numbered from 1 to 8, but the inputs are numbered 0 to 7. Good engineers like us are adaptable to a 1-bit shift like that, right? We can handle that in our heads. But when you need a score sheet to relate inputs to wire numbers and LEDs, then I think the manufacturer is out to get us.
My head hurts just thinking about it.
The product manager must have asked the engineering team to go out of their way to eliminate any shred of good design. Commonsense? We don't need it! Who arranged the LEDs to match the terminal numbers? What do you want to do, help our customers? No bonus for you! Firmware people, scramble the input numbers so we can get back on track. That will teach our customers!
After seeing this lovely bit of brilliant engineering, I called my pal at the first manufacturer back and told him his product was a paragon of intuitive virtue compared to this product. I call them like I see them, and admit when I'm wrong.