Topic: Question about PDU's and a 220/40 line... (Read 1816 times)

Well there are some assumptions so estimates and theories only take you so far you probably are going to have to experiment.

However lets assume that the heat output of your rigs IS exactly 18K BTU/HR and the AC unit can remove exactly 15K BTU/HR.  The temp in the room will rise.  You are adding 3K BTU into the room every hour.  It would be no different than right now putting a 3K BTU/HR space heater in there (no AC).  If the room was perfectly insulated the temp would keep rising forever until either the heater melted or the power cord caught on fire.

In the real world no room is perfectly insulated so there is going to be some heat loss through the walls however the rate of heat transfer depends on the difference in temperatures.  So to move 3K excess thermal energy out of the room when the outside air is say 80F probably means the room temp would rise until it reached equilibrium at 140F maybe 160F.

Now it is possible that your AC unit has more than 12K BTU cooling capacity.  Normally the capacity is rated at a certain temp differential (i.e. 90F outside 70F inside).  The cooler it is outside, and the warmer it is inside the more efficient the unit becomes.  It is also possible your estimate for the units power consumption is high and they will use less power.  You probably aren't going to know for sure until you plug them in.  However I would plan for the possibility that you either need to scale back your farm or scale up your cooling.  Then there are other factors which will vary a lot.  If you live in AZ and the room the miners are in is south facing then room is going to acquire more heat from the sun than say a shaded room on the north side of the house in Maine.

So like I said you can estimate, and plan but eventually you are going to need to plug everything in and take some measurements.  If you live in a part of the country which has dry heat you may want to look at an evaporative cooler (swamp cooler).  If you live somewhere which is humid that is pointless though (they cool by adding moisture to their air, the more moisture that is already in the air naturally the less cooling capacity they have).


Not really although any unit with a NEMA L6-30 plug is going to basically be the same so you don't need to stick to APC.  I mean these are essentially just industrial grade power strips.  Since they are being sold as used surplus I have seen them as cheap as $30 and as much as $90.  It is just the luck of the draw I guess.

Looks like fans by themselves, even with one going out and the other in and almost opposites of the are wont work.

So looks like I will have to try the AC thing, don't have anything in the way of 18k BTU window AC. But I do have a floor model AC on wheels I almost forgot about. I checked it earlier and the sticker rated it 12k.

Sad part is out house doesn't have regular AC. So... if I can close off the laundry area with a door to seal it off from he kitchen, I'm hoping the 12k AC I have will do the trick by itself.

I could try to use a window AC as well, it's rated 5,300 but I don't ant o chance tripping the regular breakers they'd both be on. Maybe I an use my killawat on the floor model tomorrow to check it out.

But what do you think of the 12k floor model by itself ?

Edit: So this eBay sellers on a bunch of f'in crack !

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=111348176399

Had listed at $60, no one bought it, told him I would buy it for $45 since it's a heavily used / aged PDU. HE responds by saying it's already below market value. So what's he do when the listing ends with no interest and one watcher which was me ?

He relists it with a $15 increase at a new BIN of $75... how stupid can some people be.

So ya, while I need a 12port PDU, I'm also not gonna bee a dumb ass and get ripped off.

Any other thoughts on a good 12 port PDU DeathAndTaxes ?

Say something I could get $50 or less shipped ?

Preferably something that doesn't have restrictions like 12a per row of plugs since with the way some of the equipment breaks down will mean I can't use all of it if there's amp restrictions per row of plugs.

ex: Two rows of 6 plugs for total of 12.

Still trying to figure out if two window fans will be enough provided the 5,220w figure doesn't go any higher than that.

You ever experiment with a window fan setup using two windows, one to draw and the other to exhaust ?

The heat should with luck be drawn out quickly and not be able to build up with where the units will be sort of diagonal to the ehaust window.

But then there's the issue of the outside air temp being drawn in ;-/

If you sell it, it would be wise to limit it (via internal breaker) to 24A.  Continual loads must be derated by 20% per the NEC.   In reality this is probably excessively conservative however if something goes wrong an insurance company is going to look for some way to shift liability. 

I jimmied together something that converts a dryer socket into 8 plugs. Powered almost 7 kilowatts worth of equipment without issue. I should probably sell it... Also have power cables with appropriate plugs that plug right into ATX power supply.

Nothing wrong with a window AC unit.   A window AC unit plus an open window venting to the outside is probably not going to work as well as you think.  If air is flowing out the window that air has to come from somewhere and it is most likely going to come from the rest of your house so it would be like running your house AC with a window wide open.

AC + sealed environment = good
no AC using forced air cooling to cool with outside air = good
AC + outside air = not good

Although experiment and see.

I'll try that but why would you say the window AC wouldnt work too well ?

It's got the side blades that pull out to close off the openings on the side.

I mean ya, it wouldnt be air tight bu it should cool a good bit with one window having an exhaust fan blowing out to draw hot air.

Edit: Window fans are same way, side blades that pull out to block openings to the side.

If you have two windows you may want to experiment with using two fans (one drawing "cool") outside air in and one forcing the hot miner air out.   Using an AC unit and an open window is probably not going to work well.

Well, there's two windows, one which wold sort of be behind the units that I can put a window fan in to exhaust and then the window AC to cool, so between that, after I put the door up I should be in a sort of sweet spot.

Yeah assumming your numbers are correct you have 3 units @ 1440W ea and 9 units @ 100W ea for total of 5220W.  Keep in mind is mind that 5220W is 18,000+ BTU/HR of heat which will need to be removed.  If it isn't removed the temp will continually increase.

So if the door is shut then you are going to need to cool most of that with the window unit (the house AC unit isn't going to run continually).  I don't know if they make 18,000 BTU/HR Window AC Units which run on 120V and use less than 15A.  If they don't you may need to scale back.  Without an AC unit you would need one massive (and loud) fan) to exhaust that heat from the room and bring in "cool" summer outdoor air.

Ty for all of this so far, got some new hard numbers.

So here's where I stand so far...

The X3 is made up of two 1Th module at about 1,440w each which the guy on the BA forums worked out to about 6.26a each. So for the X3 as a whole and one compensated module it would be 18.78a


This is what was said about the suspected amperage of the X1's and I have 6 bought and 3 compensated coming.


That being said, assuming 0.5 amp's per X1 I'm looking at 4.5 for 9, total that with the suspected amperage of the X3 plus compnsated module and I'm looking at a total of 23.28a which is just under the 80% constant usage of 24a and would work out perfectly for the AP9571 PDU.

It just means that I will have to forget the Avalon though since the standard outlet it's on now I will need for an AC unit for the room all off this will be going in. It's about 5' - 6' wide and about 20' - 25' long so it's not a standard laundry area like a closet type setup.

Only thing that will fudge the cooling is the open door to the kitchen area but is easily solved by putting back a door that use to be there and then putting a window AC in the window in the laundry area with a setting of about 60f.

There may be dryers which use 50A but yours certainly doesn't because the second number in a NEMA outlet is the amperage.  NEMA L6-30 = 30 Amps,  your dryer outlet NEMA 14-30 = 30 Amps, a "normal outlet NEMA 5-15 = 15 Amps.  Take a look at the outlet diagram upthread.


The breaker, house wiring, and outlet together make up the branch circuit.   So yes it would involve additional outlets, additional breakers in the breaker panel, and additional house wiring to connect the outlets to the breakers.

Maybe I'm confusing range with dryer, since I read one of them is like 50a or something.

Also, by branch circuit you mean additional outlets on their own breakers like the existing dryer outlet ?

There is no 60A PDU anywhere which uses a L6-30 plug.  A L6-30 plug is a 30A plug designed to connect to a 30A outlet designed to run on a 30A branch circuit and be protected by a 30A breaker.  In theory there are 50A and 60A PDU but not only are they expensive the outlets are also incredibly expensive.  In most cases it is cheaper to just use 2 or 3 30A (derated to 24A usable) PDUs.

That being said your outlet, wiring, and breaker can't safely handle more than 30A (24A continually) so that is your hard limit (regardless of how many PDUs you get) unless you have additional branch circuits run.   Also 60A @ 240V = 14.4 KW of power.  You would need something like a 4 ton AC unit running to remove that kind of heat (in addition to house's normal cooling requirements).  I don't see you doing 14.4 KW in a laundry closet.   I did a 9 KW GPU farm in by garage (powered by a pair of NEMA L6-30 outlets) and it required a dedicated AC unit.

If you just need one or two additional outlets (and total load is still under 24A) they make "C13 to C14 Y cables".

Hey DAT, new question for ya... got a few hard figures now.

Looks like I will need something closer to a 60a PDU to power everything since I'm looking at close to 19a for the X3 plus compensated module I will be running.

So you got any thoughts on a nice PDU with at leas 13 outlets that's higher than 24a so in case I do need a "bigger" PDU I can get it, but also has L6-30 for a plug ?

Ty.

Sweet, thx for all the help so far !

The place I always recommend for cables (wish they would accept bitcoins)

http://www.monoprice.com/Search/Index?keyword=c13+to+c14

The cable you are looking for is a C13 to C14.  C13 is the end that fits PC power supply.  C14 end fits the PDU.

http://www.ebay.com/itm/APC-Basic-Rack-Power-Distribution-Unit-AP9571-208V-/111341279177?pt=US_Power_Distribution_Units&hash=item19ec7517c9

Cheapest one is $60 but I like the mounting holes, since I don't have a rack I can still fix it to the wall.

Only curiosity right now is that the equipment I have coming might have standard plugs then I will need to buy PDU adapters. You may end up saying eBay but where, just in case, might a good deal be for say 12 of them ?

Lol, I just noticed but that PDU would work out perfect, 12 outlets for 12 pieces equipment.

Most PDU comes with pretty long cords.   Look for a AP9571 on ebay.  I can't remember exactly how long the cord is but I am sure it is more than 10 feet.  I have a couple I could sell but they are dirt cheap on ebay so you can probably get one there.   If you are lucky you can find one under $30 but if not under $50 for sure.   They are pretty expensive new but APC made like a billion of them in the 90s and 2000s so there are always tons of old data center surplus floating around.

Well per last estimated figures, if I ran all the equipment off the same outlet, where as I wa thinking of putting the 9 X1's in another room it might look something like this.

I'm ballparking everything because no one at BA has given firm numbers but this should be relatively close.

9 x 60w = 540w
3 x 1000 = 3,000w

Total being 3,600 if I round up for more wiggle room, the wattage works out, the amperage I have a currently open question on in their forums.

Edit: I would however need like a 10' l6-30 extension if you can recommend a safe one. It may end up being smaller in length, need to do some measuring tomorrow. Plus I'm not sure on cord size for the PDU I still need to buy.

Edit 2: On the note of replacing the outlet, my luck the landlord would just bitch about that to. They dont seem to want much done even if they dont end up footing the bill so this is the easy all be it safe out.