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Bench Talk for Design Engineers | The Official Blog of Mouser Electronics


Burning Yourself on a Resistor
On October 20, 2014 in All by Lynnette Reese
Lynnette Reese

Yes, it is possible to burn the $#*&! out of yourself on a resistor….a tiny little resistor. I did this under the supervision of an electronics technician at a bench job I had in college. The tech had hair down to his waist, wore glasses, and confirmed the imagery in Joe Jackson’s lyrics for Soul Kiss: “And all the hippies work for IBM.” As a freshman, I worked in the basement of the Physics department at LSU in the electronics repair shop. I knew nothing. He knew that I knew nothing. 

I don’t recall the exact circumstances, but I needed a resistor for a PCB. We had an entire wall of tiny drawers of passive components, and I knew enough to read the band for the correct value….but I didn’t consider wattage. 

Power (Watts) = Voltage x Voltage X Resistance. 

Translation: If you choose a resistor that is too low in wattage and you install it and power up the board, you essentially have an electric heating element. This tech was a great guy, but he felt that I would learn this wattage-thing better with some hands-on experience. After much confusion and still not “getting it,” he finally told me I needed a resistor with higher wattage. I needed a bigger one! Kids, this is why you have to learn algebra: for practical reasons like not burning yourself. 

Sometimes you have to learn things the hard way, preferably without killing yourself.



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Lynnette Reese holds a B.S.E.E from Louisiana State University in Baton Rouge. Lynnette has worked at Mouser Electronics, Texas Instruments, Freescale (now NXP), and Cypress Semiconductor. Lynnette has three kids and occasionally runs benign experiments on them. She is currently saving for the kids’ college and eventual therapy once they find out that cauliflower isn’t a rare albino broccoli (and other white lies.)


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