Leakage current on Switching Power Supplies

In order to make people power on power supply units safely, one of the critical factors is leakage currents. When the current overflows through the insulation resistance, it is called Leakage current. When the leakage current is contacted by the human body, the current flows through the human body and then flows to Earth, causing electrical damage. The difference between the leakage current test and the withstand voltage test and the ground protection test is that the device is tested under operating conditions. A human body analog impedance circuit is added to the leakage current test to simulate the leakage current through the human body under real conditions.

The leakage current standard categorized into Class I, Class II and Class III by the types of Insulation, which derived from the IEC system. Now, we list as below:

* CLASS I means that the product's protection against electric shock not only depends on basic insulation, but also includes grounding. Its leakage current limits Max.0.75 mA for the handheld and 3.5mA for the other equipment.

* CLASS II means that the product's protection against electric shock not only relies on basic insulation, but also includes additional safety measures such as double insulation or reinforced insulation, but without grounding or protection depending on the installation conditions. The Max. leakage current is 0.25 mA.

* CLASS III means that the product's protection against electric shock depends on the power supply voltage as the safety extra low voltage (SELV), and no dangerous voltage is generated therein.

Astek Power Supplies pass the tests of leakage current and relative green power regulations because we care about the safety and environments. Any inquiries, please touch us asap.