What is your Take on this Thermaltake?

[MrAl]

Hello,

This power supply is supposedly rated for 700 watts. The power supply is labeled with the following:

3.3v 24A
5v 24A
12v 52A

yet this puzzling statement is found in the paper manual (see attachment).
Note they state that "no output shall continuously provide more than 240VA under any conditions of load.."

So what do you think about this?

 

[crutschow]

I would say they are engaging in "specmanship" which is a polite was of saying they lie, particularly about the 12V @ 52A spec. The maximum is actually 20A for the 12V output.

 

[MrAl]

Hi Carl,

Well that was my first thought too, but when i picked up the case i realized there was a huge difference in weight between that power supply and my other older 450 watt power supply. The 450 watter has a 12v output that is 16 amps but is higher on the +5 and 3.3v rails, and that weighs about 10 Newtons. The 700 watter weighs 18 Newtons.

Then i was wondering, could that rating not actually refer to the entire 12v output (for example) but maybe for each individual wire coming from the 12v rails? That would limit the current per WIRE to 240VA rather than the entire 12v rail.

Did you or anyone else ever hear about this before? The thing feels like a big power supply and it has much thicker (heavier gauge) wires coming out of it than the 450 watter, but that secondary rating really threw me. And if i do interpret that rating as the entire 12v output, that would make the power supply only a 120+240+20 watt power supply (380 watts) and i have seen power supplies that low before and they are quite a bit lighter in weight. I also see a pretty big transformer inside but it's hard to see through the cracks and i can not open it or void the warranty.

What i normally see on power supplies is a rating for each output or a group of say the 3.3v and 5v outputs. So underneath the current rating they stamp something like "150 watts" or "400 watts". My other 500 watt power supply has this info stamped on it's label and so it is clear to read what spec's are for each output. But this 700 watter is strange.

 

[crutschow]

One possibility is that the 240VA rating is in error, but that seems unlikely.

 

[MrAl]

Hi Carl,


Yeah i guess that's a possibility. Too bad it leads to much confusion.

I called Thermaltake and the guy who answered the phone doesnt know what VA is !
He thinks because is states "240VA" it refers to the max 240vac input ha ha.

I didnt hear from them, so i emailed, and the reply simply stated the obvious, the spec's that are already stamped on the side of the power supply. So that didnt help at all and that was directly from Thermaltake.

 

[steveB]

My guess is that the continuous spec relates to thermal ability of the unit. Short term currents on the 12 V output are ok at 52 A, but if you run continuously, it will overheat or at least degrade the lifetime of the unit.

-just a guess though.

 

[MrAl]

Hi Steve,

Thanks for your input here too. I was hoping to hear ideas like these coming up here.

That's close to the statement i just got from Thermaltake. The guy says that the max output on the 12v line is 624 watts, as long as the +5 and +3.3 are not outputting any current. With the +5 and +3.3 at max output, that would bring the 12v line down to about 500 watts, and that doesnt seem too bad. I still asked about the 240VA spec but they did not reply on that issue. But based on comparisons to other power supplies this thing is far too heavy to be a mere 300 or 400 watt power supply.

The more i think about this the more i suspect that the 240VA output was really for the fire protection spec that was supposed to be implemented a while back in computer power supplies to prevent overheating of wires that come from the power supply to the motherboard or CPU or graphics cards (or other). The wires would be rated for 20 amps which would be 240VA on the 12v line, but as you know if the wires try to pass more than that current they could significantly overheat and melt the insulation, which could cause a fire. So they may be trying to protect against that. Since the wiring is such that there are two sets of two PCIe 8 pin graphics card power outputs where each set has it's own set of wires coming out of the power supply, that would mean that maybe each set of two can handle a max of 240 watts. The CPU connector would then be limited to 240 watts, the MoBo limited to 240 watts. That's just a guess too though.

What else is funny is i remember someone else having this problem too a long time ago but cant remember anything much about it.

 

[MrAl]

Hello again,

The nuttie guy at Thermaltake is still insisting that the 240VA in the image posted previously refers to the 240VAC input spec. It's funny too as he wrote that "240VA" means "240VAC". What kind of nut could this guy be <chuckle>.

I would agree that 240VA could be a typo for 240VAC, but the paragraph that it appears in is clearly talking about the OUTPUT not the INPUT. See attachment.

 

[kubeek]

And that is some kind of tech support? Maybe he should look for a job that suits his abilities better, maybe marketing..

 

[MrAl]

Hi,

He he, yeah you are right there

Also, i posted a picture of the manual statement in the previous post i'll repeat here...

 

[steveB]

I'll never forget the Radio Shack salesman that didn't understand the concept of digital encoding. I asked him why I shouldn't buy the CD player lens cleaning disk to clean my DVD player lens. You know those CDs with a little brush on them that wipes the lens when you play the disk? I asked because the CD player cleaner was half the price of the DVD player lens cleaning disk, and the two disks looked identical to me. I figured there might be some mechanical difference in the laser/lens system that required a slight difference, so I sought his product expertise to guide me. However, I was shocked by his answer. He said the CD cleaner would only clean the audio and not the video. Well, that convinced me to buy the CD cleaner and save half the money, but since I didn't want to make him feel stupid, I told him that, "only my audio bits are dirty".

 

[MrAl]

Hi Steve,

Wow that's pretty funny. But you know i have heard lots of stories like this from people who have dealt with Radio Shack "attendants". As you probably guessed, i have my own too i'll briefly quote. This was back in the late 1970's. I purchased a pack of 1N4148 or equivalent diodes, and all except one were bad. I took it back and when i told the guy about it he said, "Well that's about par for the course". I eventually got my money back and new diodes though, but that statement was pretty funny.

But i expected better from a company like Thermaltake. Their power supplies are not that bad so i thought their tech support would be ok too.

 

[kubeek]

Which exact model you have? For example this review shows that the tr2 700w model can do 750w without problems. **broken link removed**

 

[MrAl]

Hello there,


This one is TR2-700w also, but the "other" model number is TR2-700AL2NC-A, which is not the exact model they are reviewing. This model quotes 52 amps on the 12v line rather than 57 amp in the review.

 

[Bob Scott]

The power transformer core and its primary winding are limited to passing 240VA. The transformer can supply any rated amount of secondary current through any secondary winding as long as the 240VA total value is not exceeded.

What's the confusion here

 

[kubeek]

What's the confusion here

So that is why it is advertised as a 700W power supply?

 

[shokjok]

What is this monster powering? Perhaps it's better used in the garage to recharge multiple batteries from your vehicle and electronic devices.

 

[MrAl]

Hello again,

Bob:
Well 240VA in a DC circuit is the same as 240 watts. So they are implying a limit of 240 watts. But since the power supply is rated 700 watts this cant be true. A company like Thermaltake would not put out a power supply and say it was 700 watts if it was really only 240 watts. Not only that, but the weight of the unit is far above that of a 300 watt power aupply and almost twice as much as a 450 watt power supply, and it has thicker wires coming out of it for the power distribution.

shokjok:
It is going to be used in an AMD FX8xxx cpu system with high end graphics card. I also wanted to leave room for a second graphics card. It is unlikely that it will have to put out this power for long periods of time though.

 

[Reloadron]

Greeting and Salutations...

That pesky 240 VA thing again.

The below quote is taken from the ATX12V Power Supply Design Guide Ver. 2.2:

3.2.4. Power Limit / Hazardous Energy Levels
Under normal or overload conditions, no output shall continuously provide more than 240
VA under any conditions of load including output short circuit, per the requirement of UL
1950/CSA 950 / EN 60950/IEC 950.

The entire document can be viewed here.

Something interesting about the "Design Guide" is that it is a design guide. My take has been always that compliance is not a requirement. So while the requirements of UL
1950/CSA 950 / EN 60950/IEC 950 are spelled out I could never find information forcing compliance to those specifications.

Years ago I became more involved with computer hardware review sites than I think I ever wanted to be with a focus on power supplies. Mostly loading and testing them.

On a side and off topic note I have been scarce around here and MrAl I owe you!

I am now 100% retired and have been doing some traveling. I like this retired stuff so far. I am also into now ripping the house apart with final home improvements. Sort of butt deep in alligators as I try to remember my primary mission was to drain the swamp.

Ron

 

[MrAl]

Greeting and Salutations...

That pesky 240 VA thing again.

The below quote is taken from the ATX12V Power Supply Design Guide Ver. 2.2:



The entire document can be viewed here.

Something interesting about the "Design Guide" is that it is a design guide. My take has been always that compliance is not a requirement. So while the requirements of UL
1950/CSA 950 / EN 60950/IEC 950 are spelled out I could never find information forcing compliance to those specifications.

Years ago I became more involved with computer hardware review sites than I think I ever wanted to be with a focus on power supplies. Mostly loading and testing them.

On a side and off topic note I have been scarce around here and MrAl I owe you!

I am now 100% retired and have been doing some traveling. I like this retired stuff so far. I am also into now ripping the house apart with final home improvements. Sort of butt deep in alligators as I try to remember my primary mission was to drain the swamp.

Ron

Hello there Ron!

First, very happy to see you return to the forum. Been a long time now since i have heard from you

And now thanks for confirming that about the 'aged' 240VA requirement. I had guessed what you are saying there, but had no proof until now.
So it turns out it was an attempt to comply with the standard. What else is funny is that they may still not even be complying with it even though it is written in their manual <chuckle>. But i will assume they are just for kicks.

So the way i understand it is that each LINE should put out 240VA max. That means if there are 4 lines going to the CPU 12v feed connector the CPU can get only up to 960 watts (watts=VA in DC anyway). That should be more than enough as the big 8 core CPUs (as well as some others) draw about 125 watts and i think the max for any CPU is about 140 watts. I dont want a hot plate stove inside my computer box anyway

But what bothers me here is that this spec seems like an uninformed spec anyway. Maybe that is why we see non conformity widespread. The real problem is that the spec was put in place so that the wires themselves would not overheat, burn, and cause a fire. But a spec of 240VA or any other spec in those units (VA) CAN NOT accomplish this goal when the voltage is variable from 3.3v to 12v, which as everyone knows, is the range of voltages that the power supply has to put out in a modern computer power supply. When a spec like that applies to modern household wiring like 120vac, 230vac, etc., it is assumed that the voltage is only going to be one of 120v or 230v, and then it makes perfect sense because the current in the wire is then directly related to the wattage, which is usually close to the VA rating for most normal household products. But in the computer, at 12v 240VA means of course that 20 amps max will appear in any single wire, but geeze at 6v that would be 40 amps, and at 3v (which is close to 3.3v) that would be 80 amps !! So this would suggest that the power supply manufacturer must use HEAVIER gauge wire for the 3.3v line than for the 12v line, but we see that all lines are made of the same gauge wire. So if they apply the spec to a computer power supply, ONLY the 12v lines will be protected anyway.
So we see why this spec is not that great to begin with.

When you have to deal with a lot of alligators please remember not to try to jump over them until they close their mouths, and then jump only onto their snouts when crossing the mote or the swamp