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Questions tagged [power-distribution-unit]

Questions related to power distribution units (PDU) or mains distribution unit (MDU) which are devices fitted with multiple outputs designed to distribute electric power, especially to racks of computers and networking equipment located within a data center.

A power distribution unit (PDU) or mains distribution unit (MDU) is a device fitted with multiple outputs designed to distribute electric power, especially to racks of computers and networking equipment located within a data center.

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PDU wiring - is this normal (or even safe)?

I removed the side panel of our server rack so I can clean up some of the wiring. Inside I found the PDU was wired like in the picture. Instead of an incoming power cable, there's just 3 uninsulated spade connectors. Is there any reason for wiring…
Grant
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Best practices for power cabling racks in DC

With network cables it is easy. I use velcro-ties, coloured cables, 0U vertical cable organizers from APC on side of the rack -- easy and neat. However with power cables it was always giving me headaches. With some of the racks I am using Vertical…
bart613
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What is the difference between a PDU and a power strip (both 120V, 15A)?

I just chatted with an APC rep about upgrading the UPSes at our office. She recommended a single higher-capacity 6-outlet Smart-UPS to replace the four Back-UPS units we currently have. When I asked how she recommended plugging in all the current…
rob
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Proper Sizing for PDU's/Power in Rack

I've struggled with sizing my power sources and associated PDU's in my server racks. Somehow I feel like I'm way oversizing things based on nameplate requirements on power supplies. My simplistic approach is to look at the nameplate draw on my…
Andy
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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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Source of PDU De-Rating?

In researching PDU's I have noticed most cite a derated current at the 80% level. For example, 30A is derated to 24A: Tripp Lite: Raritan: Does anyone have anything that shows what agency this is (NEMA?) and these actual regulations? Also, does…
Kyle Brandt
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How to step down voltage from 208V to 110V

I have some racks that will be fed by 208V/20A circuits. These circuits will be conditioned and battery-backed by the facility in which these racks will live. 99% of the devices in the rack will be able to support 208V input, so I plan to use these…
Eric Dennis
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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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Things to consider when buying PDUs

I am thinking about getting new PDUs for my racks. I would like ones that are: Metered (Maybe remote monitored) Vertical Meet my power requirements (Voltage and amperage) Right number of outlets (~20) What else, if anything, should I think about…
Kyle Brandt
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Power Usage via IPMI or BIOS or?

Is it possible to check the power usage of an entire machine via IPMI, BIOS, or any other option? I have done some searching but no results have came up yet. PDUs only show the total usage, so this would be an interesting way of seeing which…
Jacob
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Using Y split cables to connect two servers to a single PDU receptacle

We have bought a few 30amp 208v PDUs that only have 9 receptacles. The servers we are connecting to those PDUs will not use the full 30amps (at 80%, or actually 40% since we use redundant power) so we need to find a way to connect more than 9…
sagi
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AP8941 PDU frozen, how to reset management interface?

I have a frozen AP8941 PDU. It still produces power to its outlets, but I can't serial in, ethernet in and even the LCD is frozen. How do I reset it without losing power on the outlets? (I prefer a simple reboot of the management interface than a…
Charlie Wilson
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Is it possible to use mixed 110V / 208V power on a single server with dual power supplies?

Is it possible to run a dual power supply server with one PS plugged into 110V, and the other power supply plugged into 208V? We've asked the vendors and they say they've never tested it or some other "i dunno" type of answer. The power supplies…
Nathan Neulinger
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PDU says to ground to rack with "thread making screw".. this is impossible?

I'm trying to use the 'thread making screw' to ground my Dell PDU to the Rack, however the metal on the rack is impossibly hard. Is this even required? The included screws don't even seem "thread making" or "self tapping".
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Can I power 2x6 socket surge protected PDUs from a surge protected UPS?

I've got a local network rack with: 24 port switch 2x voip dect bases 2x modems 1x load balancing router 1x wifi access point 1x 2bay Synology nas At the moment these are all powered via 2x 1U 6 socket surge protected PDUs. I want to add a UPS…
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