tabs ↹ over ␣ ␣ ␣ spaces

by Jiří {x2} Činčura

Disassembling a relay

2 Apr 2017 1 mins Electronics, IoT

I like taking things apart. Or putting them together. New piece of furniture from IKEA is like a small Christmas. It’s something different than programming, yet very similar, at least for me, in how the brain processes the (dis)assembling. Already as a child in school I liked learning how everyday objects work.

But there’s a small difference in understanding the concept and really seeing the real – production level quality design – device. Because for production level quality you need to work out all the corner cases here and there, understand i.e. real forces applied and so on.

So when I realized my 4 dollar relay is broken I decided to take it apart (irreversibly 😉), to see how the real relay looks inside. The idea is simple. You have some spring keeping the two contacts from touching and a coil that eventually pulls them together, if there’s juice flowing through it.

Here are some picture (excuse my sloppy soldering job):

Relay – front

Relay – side

Relay – side-front

To my surprise even the real life “implementation” of relay (alright, this is a cheap 4 dollar relay, not rated for high current, precise switching times, etc.) is pretty much the same as the basic concept. There’s a coil, some contacts and one of them is on a preloaded piece of metal acting as a spring.

Can’t be any simpler. How cool is that?

Profile Picture Jiří Činčura is .NET, C# and Firebird expert. He's focused on data and business layers, language constructs, parallelism, databases and performance. He's Microsoft Most Valuable Professional and frequent speaker. You can read his articles, guides and tips and tricks at