As we mentioned on other articles and reviews, the first place we like to take a look when opening a power supply to have a hint about its quality is its filtering stage. The recommend components for this stage are two ferrite coils, two ceramic capacitors (Y capacitors, usually blue), one metalized polyester capacitor (X capacitor) and one MOV (Metal-Oxide Varistor). Very low-end power supplies use fewer components than that, usually removing the MOV and the first coil.

This power supply is flawless on this stage, having one extra X capacitors and one extra coil. This power supply has two MOVs located after the rectification bridge (and not before as usual), physically squeezed between the two electrolytic capacitors.

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Figure 7: Transient filtering stage (part 1).

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Figure 8: Transient filtering stage (part 2).

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Figure 9: Transient filtering stage (part 3).

Now let’s have a more detailed discussion on the components used on Green Star LW-6550SG.