Alternating Current Supply Filter RFI Dc Blocker Partition Eliminates Transformer Resonance Hum Rectifier RFI DC blocking circuit introduction: eliminate ac ac 110V-AC220V mains due to frequency conversion air conditioning, electronic switching power supply, refrigerator, charger and other home appliances DC components of the interference to the AC. The elimination dc circuit built by diode and capacitor is used to eliminate and block the DC component in the AC power supply, so as to prevent the transformer from magnetic saturation or static current increase because of the DC component. Note: Any direct current on an AC power supply usually causes the coils of most large toroidal transformers to hum. The addition of RFI DC partition circuit can significantly improve power supply quality and suppress and eliminate transformer buzzing. \Performance: Working voltage: AC 110V--220V Operating current: 25A-- 50A Board size: length 50mm width 48mm height 30MM net weight: 58g _x000D_