We decided to disassemble this power supply to see what makes it different from other high-end power supplies. 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.
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 active PFC circuitry; the use of a thermal sensor on the power diodes heatsink for controlling the fan speed and for shutting down the power supply in case of overheating; the power rating of all components; the design; etcetera.
On Figure 7 you can have an overall look from inside this power supply.
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Figure 7: Inside Enermax Galaxy 1000 W.
What immediately caught our eye was the use of two transformers, meaning that this power supply has two separated secondary circuits for the main positive voltages (we will discuss this deeply on next page). This was expected, as it makes more sense to use two transformers than building a power supply with just one big transformer – all other high-end power supplies we’ve seen to date use just one transformer. On Figure 7 you can also see a smaller transformer on the right (under a transparent plastic protection), which is used by the +5VSB circuit – on all power supplies this output is produced by an independent circuitry, so this isn’t something exclusive from Enermax.
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Figure 8: The two main transformers. On regular power supplies only one is used.
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. On generic power supplies this stage has only one coil, two ceramic capacitors, one or two metalized polyester capacitors and, if we are lucky, one MOV (Metal-Oxide Varistor).
This power supply from Enermax does not use a MOV at all, being the first time we’ve seen a high-end power supply from a respectable manufacturer not using this component, which is a transient suppressor. As a matter of fact, this is the only flaw we could find on this product.
Enermax used “only” two metalized polyester capacitors, two ceramic capacitors and two ferrite coils on this stage.
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Figure 9: Transient filtering stage (part 1).
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Figure 10: Transient filtering stage (part 2).
The other coils you see on Figure 10 are used on the active PFC circuit.
Talking about active PFC, this circuit is controlled by a UCC3817 integrated circuit located on a small printed circuit board shown on Figure 11.
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Figure 11: Active PFC controller.
Now let’s have a more detailed discussion on the components used on Galaxy 1000 W.
