6 Servers on a 15 Amp Power Strip

Not sure how this power stip could possibly be working.  It is only a 15 AMP power strip and this 6 servers have to be drawing at least 3 amps each.  Someone help explain this too me?  Thanks,
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beepatAsked:
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Tory WCommented:
Your power strip is rated to safely carry 15 AMPs of power. You can push as many amps of power over it that you want (usually)  Most power strips have a function to protect against dirty power or lightning strikes but they normally don't regulate how much power can be run across them.  

Find another power strip for two or three of the servers to balance the load. The strip may handle more than 15 AMPs but it could also burst into flames as well.  This goes for any link of power not just the strip.  The wiring in your wall may well be very much over loaded too.  I would suggest getting an electrician in to do a survey for you, some may even do consultations for free.
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Lee W, MVPTechnology and Business Process AdvisorCommented:
How do you know the servers are 3 AMPs each?  Watts = Amps * Volts.  with 3 AMPs, you would expect you are drawing AT LEAST 300 Watts each.  That's a LOT of power.  You should understand that just because a power supply may be rated for 400 Watts... or 800 Watts... or whatever, that does not mean it is constantly drawing that much power.  Most of the time, at least in my experience, the actual power drawn is more like 20-25% of what the power supply rating is.  At boot, there is a spike (when the wattage available MUST meet the demand), but after things settle down (hard drives spin up, for example), idle CPUs and disks draw less power.

I would suggest you get yourself a Kill-A-Watt meter and check what the servers are ACTUALLY taking.  I suspect you'll find the ACTUAL power being pulled through the strip is more like 8-9 AMPs constant and maybe 15-18 on power-on (and HOPEFULLY you know not to power on ALL servers at once - give them a minute or two between starting).
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JohnBusiness Consultant (Owner)Commented:
As Lee noted, the supplies are probably not drawing rated load. That is "why it works".

Still, I would not put more than two or three servers on one commercial power strip. You need an adequate number of 15 amp circuits to provide for all your servers. This will also give a modest amount of redundancy in supply.
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andyalderCommented:
What is the power strip and what voltage do you have in your country? (you say -this- power strip as if you are referencing a specific one).
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beepatAuthor Commented:
Thanks for input. I know not to spun all these up at the same time. This is a new job for me and I am just auditing things that should be changed. I was wondering more about the calculations of these power strip. I wonder how many servers I could plug into this strip before issues would start.
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JohnBusiness Consultant (Owner)Commented:
I would not allow issues to start. So keep to 2 or 3 and keep each strip on a separate circuit.

Power strips have a tendency to get kicked around so a rack mounted strip is always better.
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andyalderCommented:
How are you going to avoid all the machines starting at once if you have a power outage and then the power comes back and they all start up?
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JohnBusiness Consultant (Owner)Commented:
How are you going to avoid all the machines starting at once  Yes, which is a reason why I suggest some separate building circuits.  It helps to avoid issues.
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Tory WCommented:
Ok, it seems I may need to clarify my statement and also request more information.  There are many variations of "power strips". Some have circuit breakers that will trip if a certain level of current is present, others have fuses that burn out if a certain level of current is present.  

I assumed you had neither one of these types of power strips based on the statement you made about exceeding the Amperage on the strip itself.  There is a possibility that the strip has a breaker or fuse and those items are bad or faulty, but aside from that being the case there are many "power strips" that do not have a "trip" function.  In these cases I would refer you to my former post.

My question of you is what type of power strip are we talking about and does it have a function that is supposed to trip or is it just splitting the power out into 6 different outlets? If you would post the brand and model number it could help.

Also, my statement about bursting into flames was no joke. An overloaded wire or outlet will start getting hot and can easily start fires if not monitored carefully.  This goes for servers, hot pots, or even christmas tree lights like the "Christmas Vacation" movie.
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andyalderCommented:
HP AF500A - just a guess as asker won't tell us what strip they have,
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