VOTE: Logisys 480W vs. L&C 450W

[everell]

Re: VOTE: Logisys 480W vs. L&C 450W

More work on my Raptor L&C 400 watt - lets see what this puppy can take.

Capacitors replaced:
On 12 volt line: two 1000 Mfd/16 volt Su'scon replaced with 3300 Mfd/16 volt Samyoung SXE and 2700 Mfd/16 volt Nichicon PW

On 5 volt line: two 1000 Mfd/10 volt Koshin replaced with two 3300 Mfd/10 volt Samyoung SXE

On 3.3 volt line: two 1000 Mfd/10 volt Koshin replaced with two 3300 Mfd/6.3 volt Nichicon PW

Input capacitors after bridge diode: two 330 Mfd/200 volt Koshin replaced with two 470 Mfd/250 volt Samyoung SMK

Powered up - didn't blow!

[everell]

Re: VOTE: Logisys 480W vs. L&C 450W

The main switching transformer marking on Newbie2's 450 watt L&C is "EI-33 ASG". The transformer on my 400 watt L&C is marked "ERL-35-2005". Does anyone know the significance or meaning of these markings. The transformer in my L&C looks somewhat larger.

[momaka]

Re: VOTE: Logisys 480W vs. L&C 450W

Not sure about the EI/ERL markings (I think those have to do something with the manufacturer), but the two digit number on both transformers is to indicate their size.
According to CanardPC.com , a 28-sized transformer can handle up to 200 watts, while a 35-sized one can handle 350 watts or more. So my guess for the 33 one is somewhere between 250 and 300 watts (most likely 250).
Of course the switching frequency probably plays a role in that as well. The higher the frequency, the more power that can go through the transformer.

[linuxguru]

Re: VOTE: Logisys 480W vs. L&C 450W

It depends on the core material, as well. The core power loss (which is dissipated as heat in the core) depends on the kind of ferrite - and increases with increasing frequency. Generally, around 100 KHz is the about the highest switching frequency with most commodity ferrites. However, there are specialty ferrites from the Japanese majors (TDK, Fuji, etc.) that can be used up to about 500 kHz and higher, with low core losses.

Most commodity PC PSUs with BJT switchers (which includes about 99.9% of the PSUs that are commonly encountered) switch in the range of ~40 kHz to 80 kHz.

In my experience, 28-sized EI or EE cores (made of commodity ferrites) are rarely capable of over 135 W; 33 up to 200 W; and 35 up to 250 W. Anything higher will require specialty cores, MOSFET switchers and switching frequencies in the low 100s of kHz.

[Newbie2]

Re: VOTE: Logisys 480W vs. L&C 450W

everell's Raptor 400W power supply appears to a high-end L&C power supply in my opinion:


It has a proper input filtering stage (coil, X cap, two Y caps, and an MOV) along with an actual bridge rectifier. It also has larger heatsinks than the typical L&C power supply. There are power inductors on the secondary side along with a proper amount of capacitors installed. I don't find it surprising that a larger transformer was put into it too.

It doesn't look like it has the common "Y-B200ATX" PCB design of many L&C power supplies, but everell's power supply is no doubt built very well from the factory. I guess it can put out a reliable 300W or slightly more.

[momaka]

Re: VOTE: Logisys 480W vs. L&C 450W

linuxguru: thanks for the info, it was really helpful.
So to my understanding from your post, those higher-end 400-700 watt power supplies that use a single transformer only, probably use a specialty ferrite core and higher switching frequencies (and this is why they get higher efficiency as well) - or did I get that wrong?
Also, given the same transformer using a regular ferrite core, would a MOSFET switcher be able to get more power through it than a regular BJT switcher?
I feel like I know some of the basics of SMPSs but there's probably still a lot more to learn. Again, thanks for all the info.

[ratdude747]

Re: VOTE: Logisys 480W vs. L&C 450W

everell's Raptor 400W power supply appears to a high-end L&C power supply in my opinion:


It has a proper input filtering stage (coil, X cap, two Y caps, and an MOV) along with an actual bridge rectifier. It also has larger heatsinks than the typical L&C power supply. There are power inductors on the secondary side along with a proper amount of capacitors installed. I don't find it surprising that a larger transformer was put into it too.

It doesn't look like it has the common "Y-B200ATX" PCB design of many L&C power supplies, but everell's power supply is no doubt built very well from the factory. I guess it can put out a reliable 300W or slightly more.

that looks like my allied 350w i will recap soon...

[linuxguru]

Re: VOTE: Logisys 480W vs. L&C 450W

The good 300 W to 400 W units (say Delta or Hi-Pro) have fairly large transformers - even in 35 size, they tend to be taller. This allows better heat dissipation, even with commodity ferrites.

A MOSFET can switch faster than a BJT, allowing higher switching frequencies - in the 80 kHz to 300 kHz range. In conjunction with better ferrites, shielding, output rectifiers and capacitors, this helps in the design of higher power PSUs with comparatively compact transformers. However, the relatively low margins in the PC PSU business don't easily permit the use of specialty/premium components for high-volume products.

[370forlife]

Re: VOTE: Logisys 480W vs. L&C 450W

everell's Raptor 400W power supply appears to a high-end L&C power supply in my opinion:


It has a proper input filtering stage (coil, X cap, two Y caps, and an MOV) along with an actual bridge rectifier. It also has larger heatsinks than the typical L&C power supply. There are power inductors on the secondary side along with a proper amount of capacitors installed. I don't find it surprising that a larger transformer was put into it too.

It doesn't look like it has the common "Y-B200ATX" PCB design of many L&C power supplies, but everell's power supply is no doubt built very well from the factory. I guess it can put out a reliable 300W or slightly more.

Looks like my 500W rosewill but with smaller heatsinks, smaller input caps, and less transient filter. My 500W rosewill/allied also has a little pcb above the ac receptacle that has a couple of Y caps, a coil, and maybe a X cap, can't remember.

[Newbie2]

Re: VOTE: Logisys 480W vs. L&C 450W

From this I see that Deer/L&C/Allied/Solytech can produce a decent good power supply when they put the proper components into a power supply, since their designs aren't bad at all. Also, looking at the Rosewill Stallion Series power supplies on Newegg they are reasonably priced too if someone is serious about saving some money on a computer power supply.

In fact my favorite power supply manufacturer for budget and lower cost power supplies is Deer/L&C/Allied/Solytech, after a good recap (I'm not a fan of the Jun Fu, "Saturn" YC, G-LUXON, HERMEI, Canicon, and other cheap Taiwanese capacitors they use) their decently-made power supplies are great for many computers up to the mid-end level.

[370forlife]

Re: VOTE: Logisys 480W vs. L&C 450W

G-luxon has been bought by teapo not too long ago. There are many series of g-luxon's that are rebranded teapo's.

That picture of my rosewill solytech build is a stallion series 500W.

JG did a review of the same model, but the allied/apex version. It was too labeled as 500W. It only did 350W before the primary side blew. The secondary side was up to spec with the rating, but the primary couldn't supply the needed juice to get more than 350w. Other than that though, the ripple was actually very well regulated, and it didn't get that hot. If i recall, the 5v was very stable due to having 60A of capacity on the secondary for it.

Rosewill tech support is pretty down to earth, when I read that review on jonnyguru I was a little afraid because they are based on the same design, and have all the same parts except the apex/allied had asia-x caps, while the rosewill has all YC. Anyway, I sent them that link in the email, and asked them if that would happen to my psu if I put it under a heavier load. They said that when they order them they order them with a higher rated primary side, as well as "higher" grade capacitors. Don't know how much of that was BS, but it was nice to see a tech support say something other than "sorry, I not know how use compooter"

[Newbie2]

Re: VOTE: Logisys 480W vs. L&C 450W

G-luxon has been bought by teapo not too long ago. There are many series of g-luxon's that are rebranded teapo's.

That picture of my rosewill solytech build is a stallion series 500W.

JG did a review of the same model, but the allied/apex version. It was too labeled as 500W. It only did 350W before the primary side blew. The secondary side was up to spec with the rating, but the primary couldn't supply the needed juice to get more than 350w. Other than that though, the ripple was actually very well regulated, and it didn't get that hot. If i recall, the 5v was very stable due to having 60A of capacity on the secondary for it.

Rosewill tech support is pretty down to earth, when I read that review on jonnyguru I was a little afraid because they are based on the same design, and have all the same parts except the apex/allied had asia-x caps, while the rosewill has all YC. Anyway, I sent them that link in the email, and asked them if that would happen to my psu if I put it under a heavier load. They said that when they order them they order them with a higher rated primary side, as well as "higher" grade capacitors. Don't know how much of that was BS, but it was nice to see a tech support say something other than "sorry, I not know how use compooter"

I saw that review some time ago, and I'd say that power supply in the review would still be respectable for something that doesn't need say more than 300W of power.

I don't think YC is "higher" grade compared to Asia-X since they're both cheap Taiwanese/Chinese brands of capacitors, but technical support wouldn't know anyway.

[370forlife]

Re: VOTE: Logisys 480W vs. L&C 450W

I just wonder if you could order some higher capacity stuff for the primary side and replace it.

Then there's the question of the transformer, it is labeled as a 35, but can it do 500w?