What is leakage current?

AC/DC Power Adapters — Desktop & Wall-Mount, we provide a clear explanation of what leakage current is in switching power supplies.

What is leakage current?

Leakage Current

Leakage current (leak current) is defined as the amount of current that flows from the commercial power supply: AC 100V input, through the chassis = main unit casing, to the ground.

This specification ensures that even when an AC adapter is plugged into an outlet and in use, a person will not receive an electric shock upon touching the device.

In the past, devices like washing machines were made of metal, so if the insulation between the chassis = body and the internal circuits deteriorated, there were rare occasions when touching the machine with wet hands caused electric shocks.

This happened because the deterioration in insulation caused the AC 100V from the power source to be induced onto the chassis, and when a person touched the chassis, the current flowed through their body to the ground via the feet, resulting in an electric shock.

Most AC adapter housings are made of insulating resin, so even if components are damaged due to impact (e.g., dropping) and insulation deterioration occurs, there is little risk of electric shock from touching the case. However, the DC plug on the output side is constructed with exposed metal parts, so touching it may result in electric shock.

Of course, with a properly functioning AC adapter, there is insulation between the input and output, so you won't get an electric shock by touching the DC plug.

The above specifications indicate that the leakage current is less than 0.25mA based on safety standards.

We also specialize in AC adapters with reduced leakage current for medical use. We offer a wide range, so if you have any inquiries, please feel free to contact us.

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