Power Supply Question | Bitcointalksearch.org

gecox22

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Quote from: VRobb on August 28, 2017, 01:17:17 PM

Well either way I think you're probably going to buy a PSU for this now, eh? 7A at 1400W implies 220+/- AC input...
You need 12VDC at 120A or so to run an S7 at 1400W.

You are right I will just have to buy the right power supply. Now just gotta figure out what to do with these. LOL Thanks for the help!

Quote from: fanatic26 on August 28, 2017, 01:17:40 PM

There is one piece you are missing. The PSUs draw say 6.5 amps at 208 volts on the AC side. A miner is drawing much more from the DC side.

If a miner is drawing 1500 watts from 12v thats actually 125 amps of DC current.

15 amps at 12 volts is only 180 watts.

Thanks So I would need a converter that would be rated for 125 amps but would need to be over rated for safety reason of course. Bringing it back around to cost. Would be cheaper to buy a power supply that works rather than trying to make a 24VDC/ 2000W PSU convert down to 12vdc.

Thanks for the information all.

fanatic26

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There is one piece you are missing. The PSUs draw say 6.5 amps at 208 volts on the AC side. A miner is drawing much more from the DC side.

If a miner is drawing 1500 watts from 12v thats actually 125 amps of DC current.

15 amps at 12 volts is only 180 watts.

VRobb

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Well either way I think you're probably going to buy a PSU for this now, eh? 7A at 1400W implies 220+/- AC input...
You need 12VDC at 120A or so to run an S7 at 1400W.

gecox22

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Quote from: fanatic26 on August 28, 2017, 12:36:44 PM

Why would you buy a $55 converter when you can buy a proper server power supply for the same price that will put out 3000 watts?

I wouldn't I was only showing suggestion. I was trying to better understand the information users are giving to better understand my question. I really just don't know why it wouldn't work thus why I asked the question.

Quote from: VRobb on August 28, 2017, 12:31:22 PM

Recheck your math. 12V at 15A is only 180W, and at 24V is 360W... Roll Eyes

Oh I am sure my math was wrong I was only basing the amps off a couple of S7 reviews on here. It was a example really I was just trying to get a better understanding on how it works. I was thinking if the S7 total draw was 7 amp at say 1400 watts, I didn't know if just buying a dc converter that was rated for more would work or not say 24vdc to 12Vdc rated 15 amps.

The logic I was thinking (which I know is wrong) is why I asked was if the total amp draw was 7 amps even though the power supply is rated for 84 amps since I am only drawing 7 max I could get a converter rated at 15 and still be safe. (which I know is wrong) was just trying to better understand the why it wouldn't.

And maybe my question is completely retarded.

fanatic26

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Why would you buy a $55 converter when you can buy a proper server power supply for the same price that will put out 3000 watts?

VRobb

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Recheck your math. 12V at 15A is only 180W, and at 24V is 360W... Roll Eyes

gecox22

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Quote from: sidehack on August 28, 2017, 12:13:41 PM

There really is no "cheap DC transformer". Most of the parts inside that PSU are the things required to make a DC transformer possible, as the bulk of its circuitry are probably transforming 400VDC down to your 24VDC at high current. Transformers work by coupling fluctuating magnetic fields, like AC has naturally as a result of its changing voltage, but DC with its constant voltage has to be turned into AC, run through a transformer and then turned back into DC. This requires a lot of high power switching circuits and filters and an active controller to keep everything in line.

I updated my question a little bit to VRobbs comment, The power supply and trying to use is one of these http://www.socintech.com/userfile/flatpack_komp_tech_1.pdf

But I couldn't get something like this? Since I know my draw is less than 15 amps?
https://theinverterstore.com/product/24-vdc-to-12-vdc-step-down-converter-15-amp/

sidehack

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There really is no "cheap DC transformer". Most of the parts inside that PSU are the things required to make a DC transformer possible, as the bulk of its circuitry are probably transforming 400VDC down to your 24VDC at high current. Transformers work by coupling fluctuating magnetic fields, like AC has naturally as a result of its changing voltage, but DC with its constant voltage has to be turned into AC, run through a transformer and then turned back into DC. This requires a lot of high power switching circuits and filters and an active controller to keep everything in line.

gecox22

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Quote from: VRobb on August 28, 2017, 11:29:56 AM

An easy way? Not really, at the least you'd need a high power DC/DC converter, perhaps multiple ones, and the plugs and such. Tongue

I'd not want to go that route. And I just hand wired an Objective Lens focus motor coil for one of the Laser Beam Recorders here at work so I could goof around with stuff like that... Cheesy

Thanks for the information, I figured with my luck it wouldn't be that easy. I was hoping I could just buy a cheap 24 to 12 dc transformer or something like that. But knew in the back of my head the wattage and amps would play a huge part.

What if I know the draw or amps from the miners. Say I wanted to power a S7 which is what 7 amp. I know the power rating of the 24 Power supply is 84 max amps at nominal power but I am not going to draw any were near 84 amps couldn't I get lets say a 24 to 12 v DC converter rated at 10 amps or 15 amps? As long as I don't draw more than amp rating of the converter it shouldn't it be fine?

I am sure I am forgetting something in there, just trying to understand better I guess.

VRobb

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An easy way? Not really, at the least you'd need a high power DC/DC converter, perhaps multiple ones, and the plugs and such. Tongue

I'd not want to go that route. And I just hand wired an Objective Lens focus motor coil for one of the Laser Beam Recorders here at work so I could goof around with stuff like that... Cheesy

gecox22

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So I two 24V/2000 w power supplies, I would like to try use for my miners,(just makes it so I don't have to purchase more PSU's.) Is there a easy way to convert it from 24V's to 12 volts. I would think the amps the miners are drawing or the wattage the power supply is putting out would play into to it but I just don't know so figured I would ask before pursuing it any further.

Thanks

Topic: Power Supply Question (Read 389 times)