We decided to disassemble this power supply to see how it looks like inside, what is the design used and what components are used. Please read our Anatomy of Switching Power Supplies tutorial to understand how a power supply works inside and to compare this power supply to others.
In this page we will have an overall look, while on the next page we will discuss in details the quality and rating of the components used.
On Figures 3 and 4 you can have an overall look from inside GlacialPower GP-PS550BP. The transformer on the upper right corner on Figure 3 and on the left side on Figure 4 is the passive PFC transformer. As you can imagine, passive PFC solutions add more weight to the power supply.
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Figure 3: Inside GlacialPower GP-PS550BP.
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Figure 4: Inside GlacialPower GP-PS550BP.
We can point out several differences between this power supply and a low-end (a.k.a. “generic”) one: the construction quality of the printed circuit board (PCB); the use of more components on the transient filtering stage; the PFC circuitry (even though it is passive, not active); the power rating of all components; the design; etcetera.
As we mentioned on other articles, 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, which is essential for cutting spikes coming from the power grid, and the first coil.
Even though this power supply from GlacialPower has one more component than the necessary – one extra X capacitor –, it doesn’t have a MOV, which is a sin.
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Figure 5: Transient filtering stage (part 1).
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Figure 6: Transient filtering stage (part 2).
This power supply uses a UC3845B PWM controller, which is located on a small printed circuit board, as you can see on Figure 6.
Now let’s have a more detailed discussion on the components used on GlacialPower GP-PS550BP.
