Repairing electronics without killing anyone — Introduction
In this series of articles, I would like to show how to work safely with electrical devices. It is important to know what you can do and what you can’t (and shouldn’t). You can immediately start with “safe” devices and then work your way up to more dangerous things. In the beginning you just need to know which devices are harmless and which can pose a real danger.
TL,DR: If you are starting with repairs: Only repair stuff with batteries or which are powered from an external power supply with less than 40V. Don’t do stupid things with batteries (and capacitors).
To be able to open and repair electrical devices you need the propper confidence. This confidence should come from knowledge and experience. If you try to manipulate electrical devices which do not match your knowledge and skill level, it can get dangerous quickly. If you know what you are doing you can have a lot of success (and fun) repairing many different things.
But first something has to be said:
Disclaimer
I’m just some guy on the internet. Do not believe anything I’m writing here without crosschecking. Check my references and other sources to verify what I am telling. Check the legal situation in your country, different types of electronics repair/manipulations might be illegal for not properly trained people. Everything you do is your own responsibility!
If you find any errors or do not agree what I am saying, please comment and I can correct it or explain why I wrote what I wrote.
What is safety about?
When repairing an eletronic/electric device, you can work with energies that can be harmful or even deadly. Many people have been burned or killed from electricity while reparing something, this is not a theoretical danger! It can also be dangerous for the user, when using an improperly repaired device. The device can give an electric shock or cause a fire.
But don’t despair. You can learn quickly, what is without danger. How to work on dangerous devices takes more time. In the following I want to outline different areas that I want to cover in the future and give you an idea what is important.
Understand the device
This is probably the most important point. If you don’t know what you are dealing with, you can’t properly judge it. Devices are run from different power sources and can work with different levels of energies. They can range from totally harmless (toy with batteries) to extremely dangerous (microwave). Being able to distinguish this and take the correct precautions is essential for safe working.
To get you started, if it runs on batteries or from a power supply (< 40V or thereabouts) you are probably safe to work on it, even under tension. Exception to this are devices that have big capacitors which can be charged up and shock you. Examples are camera flashes or defibrilators. If it runs directly from mains you should never power it up when it is open unless you really know what you do. Be especially careful with big capacitors. They can hold a dangerous charge for days!
Understand electricity
For many electronic repairs you do not need to know too much about electronics and electricity. You can easily replace a battery if you ordered the correct spare part without knowing anything about voltage or electric charge.
For safety, some knowhow is essential though. You need to know at what voltages it starts to get dangerous. Everything above 50V AC or 120V DC is considered, just remember 40V (too add some safety margin) and you are safe. Understanding current and power, as well as how all these values are related are important as well.
The proper process
A good process is crucial to always be safe. What do I mean by that? Every step you make or habit you have when repairing something is part of your repair process. These steps can help you to know how to troubleshoot, disassemble, reassemble and be safe. If, as a trivial example, you have a small container to put all screws in they are always in the same place, can not get lost and can not cause a short circuit in a device.
The more dangerous the device, the more important the process gets. For the devices you will start out repairing, it is enough to not mishandle batteries (poke holse, short circuit), look out for capacitors,
Proper workplace
If you want to open a small battery powered toy, you can easily do it with your kids on the floor in your living room. You will probably loose a screw but nothing bad will happen. For this kind of device no special workplace setup is needed.
In contrast, if you want to repair devices that that use mains power, a proper setup is required. Proper lighting, a dry environement and no interruption are very important. You also want to have a power outlet with RCD protection.
Respect and caution
Regardless of all the things above, you should always have respect for electricity. It is invisible and accidents can happen quickly. If you are unsure about something, lean back grab a computer and lookup what you want to do on the internet.
Conclusion
You can start repairing electronic devices right now, just stick to the low voltag ones. This is a huge range of devices, toys, computers, most electronic gadgets and much more. For the remaining things (kitchen appliances, power tools etc.), you have to learn some more things to be safe.
In the future I would like to write about the different areas I outlined above (and more). Don’t think that after having read something here (or elsewhere) you know everything and are safe in every situation. Turn on your brain, be careful, check and check again and ask around.
