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Questions tagged [power-supply-unit]

Questions related to power supply units, aka PSUs

PSU is an acronym for Power Supply Unit.

168 questions
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Why do we still use power supplies on datacenter servers?

Computers mainly need three voltages to work : +12V, +5V and +3,3V, all of them are DC. Why can't we just have a few (for redundancy) big power supply providing these three voltages to the entire datacenter, and servers directly using it ? That…
user186340
42
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6 answers

Does a 500 watt power supply always use 500 watts of electricity?

Does a 500 watt power supply always pull 500 watts? Or does it depend on the load being placed on the computer? It's a n00b hardware question. I'm trying to figure out how much it costs to run my compuer without buying a meter that actually measures…
Jim
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How do servers with redundant power supplies balance consumption?

I have several servers from the HP DL360 line (generations 5-8). Each of these servers has two power supplies installed. The 2 power supplies in each server are fed from different circuits. My question is will the power draw be roughly balanced…
Travis Beale
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How does a 3-Phase UPS distribute power?

We've got 2 UPSes in our server room. One's 3 phase, and has a 3phase supply, yet the APC network stats thing only says Incoming Voltage: 230.1 Volts The other is a single phase one with no network-type monitoring. What I'd really like to know,…
Tom O'Connor
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Can Running a Server's Redundant PSU on Different Circuits Damage It?

So I've been tasked to document and review the status of the UPSes for my current employer and identify any changes that need to be made. Generally easy stuff, however I came across a few units that are plugged into both regular power and a UPS…
Insomnia
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How can I determine the power demand of an HP server's power supply under load?

I bought an HP DL360 G7 1 U rackmount server. I am looking to put it in a colocation facility. The issue is almost every facility I have seen either limits the amount of power I can access or charge extra for more power over the base amount…
ianc1215
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Can I hot-swap a 2-PSU server from 120 to 240 volts?

I'm migrating a server with 2 PSUs from 120 volts to 240 volts, and I'd rather not take it offline. It seems like I should be able to just move the PSUs to the new voltage one at a time, since they are not connected to each other. Would it cause…
user348965
10
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3 answers

How can I calculate if a UPS is sufficient for my requirements?

I am not that of an electricity knowledgable person, so I'll try to put as much info as possible. I have a Rack Mount UPS of 1800 Watts Model: PRP 3050 RM (in total I have 2 of these - talking about one specifically) I had to change it's batteries…
Saariko
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Redundant Power Supply Sloshing (If sloshing is the right word)

I have a Supermicro Redundant Power Supply with two units in it. I also have two UPS units, one for each of the Power Supplys. I was watching the LCD on the UPSs for the watt usage. The total watts equal about 400 Watts. This is where it gets…
xriri
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Maxing out both PDUs in a rack with redundant power

If I have a rack full of servers using redundant power supplies, and I'm keeping the amps at 80% (16A of 20A), isn't this still asking for trouble in the event of a power loss on one of the circuits? If power is distributed 50-50 (e.g. an average of…
Matt Beckman
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Power Cables Required to Switch from 120v to 240v for Dell Poweredge Servers

We have a cabinet of servers and other hardware (switches, firewalls, etc) that all are currently running on 120v. I've confirmed that the power supply for all of our devices support both 120v and 240v and I understand we'll need to get a 240v PDU.…
Dan
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Is it safe to remove power from a linux computer in run level 0?

I am working on power supply to a Raspberry Pi where changing the state of one of the GPIO lines shuts off power immediately. Is it safe to do this in run level zero, or is there more shutting down to be done from there before power off? If not is…
Xian
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Server power supply failures?

I have 6 servers both with 2 power supplies attached to an UPS. I want to add 4 more servers but the UPS is full and due to budget restriction I couldn't buy a new one for months. The 6 + 4 new servers are running essential services (high uptime…
Kami
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How do I monitor redundant power supplies on a Dell server?

I'm purchasing a Dell R610 with redundant power supplies. What is the best way to be alerted in the event that one of the power supplies fails? I'll be running Windows Server 2008 R2. Since this machine will be at a colocation facility, I won't…
user30101
6
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2 answers

At my wits end. What could cause my server to randomly hard reset? (Seems to be related to ZFS)

I have a server that I built years ago that has worked like a champ. But within the past few months it has started to become seriously unstable with no discernible pattern. I have been debugging it and swapping out parts to no avail. I have replaced…
Zhro
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