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Hi, i'm a computer programmer but when it comes to electrical stuff I have no clue what I'm doing. I'm trying to figure out the safety of my soon-to-be server farm setup.

I have a room where I want to run a few computer servers totaling about 1760 watts 24/7. My biggest concern is the 1250W server. Will my outlets handle it? How can I check? I just used a kill-a-watt with a 1875W blow dryer and its actual usage was about 1519W.

Does this mean I could use about 1500W 24/7 safely? I would then move the smaller servers to another room, if this makes a difference?

Thanks!
 

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I took some pictures, I'm guessing I need to figure out which circuit my server room is connected to right?

I don't know how to verify this without turning off each circuit right now, so could we assume the lowest... 15 amps?
 

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... a few computer servers totaling about 1760 watts 24/7. My biggest concern is the 1250W server.
First, what was the source of that 1760 watt number? Are those nameplate numbers? Or did you actually measure the servers while in operation elsewhere? The reason I'm asking is that nameplate values are typically overstated by about 50%. That applies on Dell, HP, etc. If those are nameplate values, you'll be able to get by on quite a bit less. Our nicely-tricked-out Dell R710s, for example, generally run less than 500 watts.

And don't forget the UPS/surge suppression. If they're servers, you'll want them to stay up, at least through the momentary power glitches.
 

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Are you using UPS's for these servers as well?
 

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First, what was the source of that 1760 watt number? Are those nameplate numbers? Or did you actually measure the servers while in operation elsewhere? The reason I'm asking is that nameplate values are typically overstated by about 50%. That applies on Dell, HP, etc. If those are nameplate values, you'll be able to get by on quite a bit less. Our nicely-tricked-out Dell R710s, for example, generally run less than 500 watts.

And don't forget the UPS/surge suppression. If they're servers, you'll want them to stay up, at least through the momentary power glitches.
Most of these servers are purpose built servers and not the typical server. The wattages are accurate readings on full load (normal operation), which was from its performance testing.

The 1760W is the single 1250W server plus a few others I just added on.
 

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Are you using UPS's for these servers as well?
I will be. My current UPS handles my workstations fine with max 450W (at least that's what I think it means on the box).

So I think I have to find a UPS that can handle 1250W+ and dedicate it to the big server.

Attached is my current UPS.
 

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If your panel isn't labeled to identify which breakers support different areas of the house then you need to do that. Turn everything off in the house, then turn off one 20 amp breaker and plug the light into each outlet until you find all that are dead. Then turn that breaker on and the next one off and repeat. It won't take that long to map out the house.
If your server room shows to be a 20 amp breaker, that will support 2400 watts but only plan to load it to 80% or 1920 watts. Use your Kill a Watt to see what your servers actually draw for power. As mentioned already, that number on the back is that maximum the server is capable of drawing. The current draw is dependent on how much memory is installed, the number of HD's, the number of plug-in cards and what ever else can be connected. It also depends on what board and processor are installed that the power supply has to support.
 

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I will be. My current UPS handles my workstations fine with max 450W (at least that's what I think it means on the box).

So I think I have to find a UPS that can handle 1250W+ and dedicate it to the big server.

Attached is my current UPS.
That is not really a UPS, it is garbage. Going back to your original question regarding the circuits. Best thing to do, is if you own this place, pull dedicated 20 amp circuits of 12/2 or 12/3(MWBC), since in reality, you probably need at least a min. of four circuits, more depending on how many computers, monitors, printers, and other devices you have in that room. Only way to know that is by doing a load calculation. Also with the extra load, your HVAC will most likely need upgrading, since it will not be able to handle the amount of heat that the computer equipment will be putting out. Trust me, I know from first hand experience, from dealing with telephone equipment on board a ship in the Navy.

As for the UPS, get a real one, or a whole house backup system just for the computer equipment, until either you can shut it down, or until a good quality genset can take over.

Now of course, if you are really into computer programming, you would know that it is cheaper and easier to run a decent server with multiple Virtual machines, vs. multiple computers as servers. Then you would only need one 20 amp circuit and one decent good quality battery backup with power conditioner system that is used in a Business application, not that garbage that they sell to illinformed consumers.
 

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If your panel isn't labeled to identify which breakers support different areas of the house then you need to do that. Turn everything off in the house, then turn off one 20 amp breaker and plug the light into each outlet until you find all that are dead. Then turn that breaker on and the next one off and repeat. It won't take that long to map out the house.
If your server room shows to be a 20 amp breaker, that will support 2400 watts but only plan to load it to 80% or 1920 watts. Use your Kill a Watt to see what your servers actually draw for power. As mentioned already, that number on the back is that maximum the server is capable of drawing. The current draw is dependent on how much memory is installed, the number of HD's, the number of plug-in cards and what ever else can be connected. It also depends on what board and processor are installed that the power supply has to support.
Alright so a 20 amp can handle 1920W and 15 amp can handle 1440W?

I guess I'll have to map the house tomorrow so I don't get yelled at when everything is in use :laughing:

As far as the server usage, they are purpose built and will be running full load at the numbers I mentioned above, unless I tweak them lower. These are number crunching machines working 24/7 :)
 

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That is not really a UPS, it is garbage. Going back to your original question regarding the circuits. Best thing to do, is if you own this place, pull dedicated 20 amp circuits of 12/2 or 12/3(MWBC), since in reality, you probably need at least a min. of four circuits, more depending on how many computers, monitors, printers, and other devices you have in that room. Only way to know that is by doing a load calculation. Also with the extra load, your HVAC will most likely need upgrading, since it will not be able to handle the amount of heat that the computer equipment will be putting out. Trust me, I know from first hand experience, from dealing with telephone equipment on board a ship in the Navy.

As for the UPS, get a real one, or a whole house backup system just for the computer equipment, until either you can shut it down, or until a good quality genset can take over.

Now of course, if you are really into computer programming, you would know that it is cheaper and easier to run a decent server with multiple Virtual machines, vs. multiple computers as servers. Then you would only need one 20 amp circuit and one decent good quality battery backup with power conditioner system that is used in a Business application, not that garbage that they sell to illinformed consumers.
I am renting so I have to make due with what I have. I won't be running any peripherals in this room... just the 4 headless servers totaling 1760W, which I may move the smaller ones to another room if the server room circuit is 15 amp.

As far as load calculation, I'm am pretty sure sure it will average around 1760W total.

Good point on the HVAC, I have a central A/C which I don't know how well it will cool the room... hmm if I get a portable A/C for that room that would only increase the load =/. I could just have a fan blowing hot air out the door. What are my most cost efficient options here?
 

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Okay, right off the bat you're going to have some heat load problems in that room. And probably an APC SmartUPS 1500 (~$500, IIRC) or equivalent. If you want everything on UPS, you might be looking at a 2200 (~$1k). Unfortunately, that's a fair chunk of change. And your HVAC solution will probably be another chunk. I run a data center for a living and it's not a trivial task to set up a good home server room. 100% of your power will effectively be converted to heat and blown into the room. What kind of budget constraints do you have?

And gregzoll has a good point - a single server with multiple VMs might be a good alternative to multiple machines.
 

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Okay, right off the bat you're going to have some heat load problems in that room. And probably an APC SmartUPS 1500 (~$500, IIRC) or equivalent. If you want everything on UPS, you might be looking at a 2200 (~$1k). Unfortunately, that's a fair chunk of change. And your HVAC solution will probably be another chunk. I run a data center for a living and it's not a trivial task to set up a good home server room. 100% of your power will effectively be converted to heat and blown into the room. What kind of budget constraints do you have?
Not a lot? I honestly did not think of how bad the heating would get. Maybe a couple hundred dollars max.

Note, these servers will only be on my local network and inaccessible from the internet (assuming no one hacks me :mad: ). If I loose power, it is OKAY to shutdown within minutes (with cheaper UPS). More important is having surge protection.

So maybe I could still split the servers into two rooms to separate power load and heat? Does this sound reasonable?
 

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As far as the server usage, they are purpose built and will be running full load at the numbers I mentioned above, unless I tweak them lower. These are number crunching machines working 24/7.
Those are not servers. They are computers running an application, which can be done on one computer running multiple Virtual machines as I have already stated. I know that you look at this as not a hobby, but I and probably a few others look at it that way. BTW, have you realized the cost that this will inure, with the computers running 24/7, plus the amount of heat generated, which means that your a/c will have to run more to keep the whole house cool.
 

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Those are not servers. They are computers running an application, which can be done on one computer running multiple Virtual machines as I have already stated. I know that you look at this as not a hobby, but I and probably a few others look at it that way. BTW, have you realized the cost that this will inure, with the computers running 24/7, plus the amount of heat generated, which means that your a/c will have to run more to keep the whole house cool.
Yes the electrical costs will run me a couple hundred per month and is not a concern.

I live in Arizona so most of the year my a/c is on anyway. I will just have to crank it lower.
 

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I didn't want to get into the details of my setup since the concern is mostly about the electrical usage, it's safety, and heat produced from ~1760W, so I called them servers when really they're devices. But thank you guys for your suggestions on using virtualization! :D
 

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These aren't ordinary servers. They're devices that do number crunching.
If you have a machine with multi-processor Xenon chips sets, you can do it with one machine. Or do it with a blade server, but you would need a 240vac supply at that point. It has and can be done with one machine running multiple Virtual machines.
 

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If you have a machine with multi-processor Xenon chips sets, you can do it with one machine. Or do it with a blade server, but you would need a 240vac supply at that point. It has and can be done with one machine running multiple Virtual machines.
You have no idea what his specific application is, so telling him to use less hardware and more VM's isn't very helpful. That's like telling a professional welder to use a 120V wire-feed machine because it uses less power than a 300A stick welder. Virtualization of that type is great for some servers, but almost useless for most number crunching purposes. Many number crunching applications are only efficient if there is a hard drive and large amount of memory available for every few processor cores. Virtualization does absolutely nothing to increase memory bandwidth, and obviously doesn't increase the actual processing power available for a given hardware setup (in fact, it decreases it due to overhead). You can't replace a supercomputing cluster with a few Xeon cores and some VM's. If he needs the power, he needs the power.

This isn't a bitcoin farm, is it?
 

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Yes the electrical costs will run me a couple hundred per month and is not a concern.

I live in Arizona so most of the year my a/c is on anyway. I will just have to crank it lower.
You will pay substantially more for AC with this additional heat load, and may need to add a dedicated cooling unit (window AC or mini split system) just for the server area. This is equivalent to running a hefty space heater 24/7.
 
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