A beginner's safety guide to repairing

Do(n't) try this at home - general safety tips

  • Think about the risks that might arise during your repair and how you can best avoid them. 
    Can something jump off or move that could hurt you? Could something get hot and burn you? Can hot water, steam, microwave radiation or anything else dangerous escape from the appliance? Can 230V or any other dangerous voltage be touched? 
     
  • During the entire repair process, keep an eye out for anything that seems out of order, such as discoloured wires, damaged and broken parts, broken housing, suspicious smells. 
     
  • Do not carry out potentially dangerous repairs alone. Make sure there is someone around to help or call the emergency services.
     
  • If you do not feel safe, stop working and call for help.
     
  • Disconnect all power sources before opening your device. Never work on anything that is plugged into a wall socket. The device should be physically unplugged, not just turned off. If possible, remove the battery before you start disassembling anything.
     

Repairing is something you learn gradually. Watching instructional videos or manuals and occasionally attending a Repair Café will increase your knowledge of how products and appliances are put together.

Is DIY still completely new to you? Then start with very simple objects and repairs. Don't try to repair electrical appliances yet, for example. Or take electrical appliances to a Repair Café and do the repair under the guidance of a more experienced repairer.

Ensure a safe and tidy workplace

  • Make sure you have good lighting so that you can see what you are doing.
  • A clean surface ensures that you can easily see and retrieve loose parts. Always tidy up your tools, sweep up sawdust and other rubbish in good time, etc.
  • You will need electricity for many repairs. Make sure you have enough sockets / extension leads, but make sure that you and others don't trip over the wiring. Always use grounded sockets.
  • Skin contact: take care that your skin does not come into contact with hazardous substances or with aggressive adhesives. Use gloves and/or safety goggles if necessary.
  • An accident, big or small, happens quickly. Make sure you always have first aid equipment nearby. It is also best to have a fire extinguisher or fire blanket.

Tools

  • Make sure your tools are high quality and operating correctly. Sharp things need to be sharp, straight things need to be straight. A blunt saw can unexpectedly slip off the cutting surface, with all its consequences.
  • Be careful with tools that get hot, such as soldering irons. Never leave a hot soldering iron unattended or near flammable items.

The repair itself

  • Think carefully. Before you put a screwdriver into something, think carefully whether you can solve the defect in another way. Is it really necessary to take apart the broken hoover, or is the cord simply worn out? Or maybe the hoover hose is clogged?
  • If in doubt, don't do it. If you have any doubts about the safety of an appliance, it is best not to start. If you think your appliance is no longer safe after repair, it is best to say goodbye to it.
  • Ask for help. If you can't work something out, don't be stubborn, ask for help. Are you not an experienced repairer yet? Then it might be safer to take your appliance to a Repair Café in your neighbourhood. There you will find experienced repairers who are only too happy to help.
  • Don't attempt to repair dangerous appliances. Some appliances, such as microwave ovens and old-fashioned televisions, are best avoided. These appliances can have high voltages, even if they are not plugged in.
  • Take photos before and after you dismantle a part and make notes if necessary. This will ensure that you can put everything back together again in the right place later.
  • Test safely. Keep some distance when you test the item for the first time after repair.
Power supply block with label showing that the input voltage is between 110 and 240 Volts, and that the output voltage is 4.75 Volts.
Power supply block with label showing that the input voltage is between 110 and 240 Volts, and that the output voltage is 4.75 Volts.

Additional measures for electrical appliances

  • Before opening the appliance:
    • Turn off the power: Unplug the appliance. The appliance must be physically unplugged, not just turned off. If possible, remove the battery before disassembling anything.
      Avoid damage by static electricity. Work on an ESD mat or use an ESD wrist strap.
  • Check the plug: if the plug and/or the power cable of a piece of equipment are in poor condition, replace them before switching the equipment on again.
  • Check the voltage. Appliances that you can plug into a power socket often have a transformer. This transforms the 230V AC from the mains to a lower AC voltage. After the transformer you will often find a rectifier that converts the lower alternating current into direct current. The area where there is high AC voltage is particularly dangerous.


With some devices, such as laptops, smartphones or clock radios, the transformer and rectifier are located in a separate power supply block. This block shows what voltage goes in and out. If your device is only powered by a low output voltage (e.g. 5 or 12 Volt), it is usually safe to work on this part of your device.

The 2 round components are round and therefore broken. Photo: Bushytails at English Wikipedia Source: https://upload.wikimedia.org/wikipedia/commons/9/96/Badcaps-tayeh-4.jpg
The 2 round components are round and therefore broken. Photo: Bushytails at English Wikipedia Source: https://upload.wikimedia.org/wikipedia/commons/9/96/Badcaps-tayeh-4.jpg

After you have opened the unit, but before you put power back on it: 

  • Check for short circuits. You can do this by measuring the resistance with a multimeter. If the input resistance (e.g. before and/or after the rectifier) is lower than expected, this may indicate a short circuit, if it is higher, this may indicate a bad contact. If there is a ground at the plug of the device, also measure the insulation resistance. This is the resistance between the ground and other points in the circuit of your appliance. This resistance must always be high.

Beware: only take resistance measurements when there is no voltage on your appliance. 

  • Do not use the multimeter to measure current, unless you are very familiar with what you are doing. A current clamp is safest for this task.
  • Check the insulation of the wires. If the insulation is damaged, it is best to replace the wire.
  • Check whether any components are bulging, because these are broken/unsafe and should therefore be replaced. Be careful when replacing polarised capacitors, diodes,...: make sure you insert the positive pole (the longest leg) of the new component where the old one was. On the Bad Caps Forum you can find help with capacitor issues.

The moment you put power back on the device: 

  • Do you need to re-energise the device to test something? Be very careful and turn off the power as soon as possible, especially if you see sparks, if something gets hot or smells burnt.
  • If possible, use a current limiter. Slowly open the current. If the voltage does not build up, if you see sparks or something gets hot, disconnect the appliance and check what is wrong.
  • If possible, use an isolation transformer. This will reduce the risk of electric shock.

The moment you put power back on the device:

  • Do you need to re-energise the device to test something? Be very careful and turn off the power as soon as possible, especially if you see sparks, if something gets hot or smells burnt.
  • If possible, use a current limiter. Slowly open the current. If the voltage does not build up, if you see sparks or something gets hot, disconnect the appliance and check what is wrong.
  • If possible, use an isolation transformer. This will reduce the risk of electric shock.

Source of this information

The information shared in this article is based on the information shared by Restarters, Repair Café Den Haag, Avansa Limburg and iFixit. For the original article, please check: 
https://wiki.restarters.net/Scared_to_Repair%3F, http://www.repaircafedenhaag.nl/wp-content/uploads/2015/02/RC_veilig_werken.pdf
https://issuu.com/vplimburg/docs/veiligheid_en_bescherming_in_je_repair_caf__def and https://nl.ifixit.com/Info/Device_Safety