Some of you wrote that highlighting a button is a great idea and helps remain concentrated on the repair task.
I hardly comprehend this because the only times I saw that kind of solution was when the operator doesn't know and don't want to know anything about what he's using: for example a client of mine wants to know only what button to press to turn on and off his PC and what icon to click on to use his invoicing software. Nothing else is needed and interesting. He learnt the steps needed to create an invoice and nothing more. If something different than he's expecting appears on the screen he goes mad. He's not a computer addicted and doesn't care anything about computers. He put a sticker on the power on button because he was going mad trying to power his desktop by pressing the reset button. He DON'T KNOW his instrument.
In the same way I thought that a PSU marked in that way is operated by someone that is not electronics addicted. Someone that doesn't understand or that have never operated a lab equipment. Also because it's not exaclty "enable and disable the output", but more a "turns on / turns off" (literally), something written by an inexperienced user.
There are plenty of buttons and knobs to operate while doing troubleshooting, so you cannot stay focused only on the DUT and almost ignore the surrounding, you must know what you're doing with your instruments.
For me is hard to accept that highligting the output enable of a PSU is a great idea, but thank you for sharing your points of view.
I worked for an ISO-9000 shop. I wrote a test procedure to test a board. Red positive wire of power supply to terminal X and black negative wire to Y. Tech was unable to get any board to pass. I was dinged because I didn't say to use a DC power supply, he used an AC supply.
So sometimes techs are simply dumb. This is what I thought when I saw that pic.
So they will have had apprentices that didn't know to read on English, and these began to touch all the buttons without having idea .
On resume, the lab's owner were until the nuts of have to reconfigure the instrument
I would never let touch a single instrument to someone that press button randomly. And if I'm not wrong, that PSU has a lock for its config.
Judging by the filth caked on that well prodded button I guess it became too hard to read. Hence the label.
heheh