Switching Mode Power Supplies and GFCIsSTART QUOTE:
As explained earlier, RF noise filtration circuits in SMPS (Switching Mode Power Supply) generate intentional Earth Leakage Current. SMPS are used extensively as DC power sources in modern day electrical / electronic devices e.g. Audio / Video / Computing devices, power supplies, battery chargers etc. A single GFCI outlet / GFCI breaker may be serving multiple SMPS loads and therefore, will be sensing the sum of all the Earth Leakage Currents and, if the sum is > 4 to 6mA after connecting this unit, the GFCI will trip.
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