Currently we are using 120v to power our servers. We are thinking of changes over to 208v for our new DC.
What are the pros and cons between the 120v and 208v?
Also we currently use 120v Geist powerstrips, if we switch to 208v powerstrips, would I need to get 208v server power cords or would the standard power cords work.
You will run into cost upgrading your power to 208v.
you will eat up double the number of circuits in your data center, so be sure you have enough.
You will need to determine what power strips to settle on. I like ServerTech for nice ones, APC 7841's if I have to.
If you are converting racks, you will need to determine when you can shut the servers down to upgrade the power. I have talked to HP about their servers being able to plug both flavors in at the same time. They said you can do that...but I'd get pretty nervous doing it.
you will also need to get new power cords for all servers. The end that plugs into the server will stay the same, but the power strip end will need to be a C13. http://www.zj-yunhuan.com/products_i...ndards_SZ3.jpg
Some servers use C19 ends...I have a few Dell servers that do. http://www.switchbox.com.au/images/p192002.jpg
On the other hand, you will double the amount of available amps...meaning you can fill up a rack with servers rather than having it maxed out at 2/3 or 3/4 physical capacity.
I've got some projects going that may force a complete upgrade to 208, 20 pairs of strips. If you are planning to upgrade many racks, you might want to call around to get a deal. I did that with Server Tech directly and recieved quite a discount. I get the strips cheaper than my normal vendor can get them!
You will run into cost upgrading your power to 208v.
you will eat up double the number of circuits in your data center, so be sure you have enough.
You will need to determine what power strips to settle on. I like ServerTech for nice ones, APC 7841's if I have to.
If you are converting racks, you will need to determine when you can shut the servers down to upgrade the power. I have talked to HP about their servers being able to plug both flavors in at the same time. They said you can do that...but I'd get pretty nervous doing it.
you will also need to get new power cords for all servers. The end that plugs into the server will stay the same, but the power strip end will need to be a C13. http://www.zj-yunhuan.com/products_i...ndards_SZ3.jpg
Some servers use C19 ends...I have a few Dell servers that do. http://www.switchbox.com.au/images/p192002.jpg
On the other hand, you will double the amount of available amps...meaning you can fill up a rack with servers rather than having it maxed out at 2/3 or 3/4 physical capacity.
I've got some projects going that may force a complete upgrade to 208, 20 pairs of strips. If you are planning to upgrade many racks, you might want to call around to get a deal. I did that with Server Tech directly and recieved quite a discount. I get the strips cheaper than my normal vendor can get them!
Thanks cernst. I would not try to switch a current DC over to a 208v, that would seem like a nightmare. I would start this with a brand new DC. I'll check out the powerstrips you recommend.
Without a doubt, leave yourself flexibility in a new DC. With the growing demand for denser servers you will find a need for 208, 120 and even 3phase power.
I am planning on using StarLine busway in my new DC. This will give me the capability to use from 5-15's to L2130 outlets to supply power locally. As for power strips, look at numerous vendors and see which ones will work best for your situation. I will likely be using a Raritan solution because they connect into CommandCenter so I can control the outlets and IP KVM all from the same source.
After hearing horror stories about ServerTech's sales practices, I won't even look to them for anything. They tried to up-sell me when I wanted information on a specific product when I was specifying components for a project. Not a good way to make customers! Not to mention that fuses are a cheap way out from using breakers.
we just looked at this and unfortunately the costs outweigh the benefits currently. I think it must be a conspiracy with the consultants and the power equipment manufacturers.
a 208 power strip is still running 3x the cost for the same number of ports. this makes it untenable. if it were the same or only slightly more - it would make a lot of sense.
as well a previous poster mentioned that the breaker takes up double the space so you have more distribution costs.
the servers really dont use that much less power - so you only drop a slight amount of heat load. overall our cost savings did not nearly show a reasonable payback on the project.
for now its relegated to blade servers and other very high power devices that need the power within the chasis.
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With three 120v 20A branch circuits per cabinet (cheapest power strips), you're using three circuit breaker poles per cabinet. With two 30A 120v per cab, you're using only two poles; and with one 30A 208v, you're also using two breaker poles per cabinet. All three options give you enough power to fully build-out most cabinets. 208v doesn't really burn-up more breaker pole space, unless you underutilize the branch circuits.
With 208v, the load of each server is distributed across two phases, making the change in phase loading at the panel smaller with each new cabinet you fill (unless you're using three 120v 20A circuits, which can also be good). Neutral sees less load with 208v, reducing harmonic load on your step-down transformers.
It's easier to manage power when everything in the cabinet is on one 208v 30A branch circuit (no juggling power between circuits). On the negative side, if you pop the big branch circuit, you lose the whole cabinet, unless you have A/B redundant power. Recently, a power supply of mine died in spectacular fashion, popping the breaker on the 208v 30A power strip when it died. Luckily, the power strip has two banks of receptacles, each protected by its own 15A breaker. So even though I had a single power strip and a single circuit, only one 15A breaker popped, and I didn't lose the cabinet.
You're right about the costs being higher. If you replace three 20A or two 30A strips with a single 30A 208v, that helps soften the blow.
I don't think the C13 connectors are quite as wiggle-resistand as NEMA5-15Ps. I haven't seen any 208v "Y" cords; and they're harder to find in odd lenghts.
I think the 208 pricing will come down over time as more demand and competition grows for it but it jsut doesnt make sense for us now. we install 208 for some customers currently that have blad servers or high power routers that need it.
I definatly like it better - but its pricing needs to work in the overal equation.
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netdepot.com premier unmanaged servers
tranxactglobal.com amazing managed and unmetered servers
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Yes, for a rack with 20 or fewer servers, 208 volt pricing seems to be okay now. Just using APC's list pricing as an example:
one 208x30 AP7541 $280 (20 receptacles)
two 120x30 AP9560 $414 (20 receptacles)
three 120x20 AP9563 $378 (30 receptacles)
If you are filling a cabinet with 20 2U servers and a switch, then the AP7541 will be one receptacle short; but for many people (including me), it's enough.
There are more "off brands" (cheap) for 120x20 power strips, so you can still get three 120x20s cheaper if that's you're priority.