Safety Tips for Power Supplies

Safety comes first when dealing with power supply adaptors. Power supplies work as decouplers, and are also used to reduce ripple and smooth out voltage, store charge and block DC current. 

They come in a range of voltages from a 5V adapter for a raspberry pi, a 12v power supply for a laptop or desktop applications, up to larger 24V PSU that can be used for servers and telecommunication purposes  medical, automation and other applications where size, portability of equipment, low heat and fundamentally fail-Safe operation is important.

Following some simple guidelines and buying products from reputable supplies that value endurance, for example, RS Components, will ensure a long-lasting and reliable power supply for your equipment. 

Choosing the right adapter 

Match the Voltage. Check the sticker of the adapter and the device to ascertain that the output V matches the rated input V.

Ensuring your cost savings does not compromise safety 

It is better to pay a bit more for a reliable and trustworthy brand to make sure you get a power supply that is safe and can be depended on. This includes the electrolytic capacitators which need a high quality fluid to prevent short term effectiveness and even explosions. 


Fans are a  critical component of all PSU’s.  Good quality fans will ensure that the supply delivers reliable service. The top performing fans are Fluid dynamic bearing (FDB) and hydro dynamic bearing (HDB) fans (50-150,000h lifetime).  These offer low noise output as well as increased lifetime.  The Double ball-bearing fans (40-50,000h lifetime) are also recommended. 

To prevent overheating make sure that the ventilation holes found on the surface of the fan installation and on the opposite surface are kept uncovered. 

Mounting Method

The power supply must be mounted in the correct direction as per the installation instructions.  If not, the poor heat dissipation will cause the internal temperature of the power supply to increase which will result in failure of  the power supply.

For power supply adapters larger than 12V:


Insulation will last longer when you choose the recommended insulating material.   Check your data sheets to establish the correct insulation required. As the applied voltage increases, discharge phenomena can occur, so the insulation must be able to withstand voltage at safe levels.  Withstand voltage can decrease due to a variety of reasons such as dirt or dust, and humidity.  Voltage increase can also result in leakage. 

Handling high voltage output cables

Always use the advised instructions to make connections when applying high voltage.

For direct soldering be sure to place a cover over the object.  Choose an insulator with enough dielectric strength or one that has ground potential.  

Securing the cable mechanically ensures that any exertion of force on the cable is not concentrated entirely on the area being soldered.

Always observe the following safety precautions.

  1. Always attach a ground wire
  2. Do not touch high voltage areas
  3. Cover high voltage areas
  4. Make others aware of hazards 

Follow the data sheets

Your product will include data and installation sheets which will guide you regarding the correct methods of installation and safety procedures.  If you are purchasing a power supply over 12V, consult with an expert to make sure you are following the safety protocols.