> 4. This is the topic for electrician, not for IT guy. (Ok, I'm licensed > electrician with little mainframe knowledge).
Little mainframe knowledge? Are you trying to give me an inferiority complex? 😊 That's like saying Peter Relson knows a little about operating systems!@ <grin> Bob -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Radoslaw Skorupka Sent: Thursday, May 6, 2021 9:23 AM To: [email protected] Subject: Re: Datacentre Rack power clarification To complement: 1. Power is measured in Watts. Dot. No Amperes. 2. AC current power formula is a little bit more complex. It is P=U x I x cos(fi). It is matter of "passive power" caused by coils and capacitors. That's for linear receivers. To make long story short, most IT equipment has cos fi very close to 1, so it is safe to assume just U x I just like in DC realm. 3. Nominal values written on identification plates are tricky. This is maximum value, good for fuse choice, but not for air condition, etc. The difference can be quite big. Excercise: check your laptop power supply and use wattmeter to check real power consumption. In case of lack of wattmeter use ammeter and assume cos(fi)=1. Servers are different animals, but the differences *are* still important. BTDT. 4. This is the topic for electrician, not for IT guy. (Ok, I'm licensed electrician with little mainframe knowledge). -- Radoslaw Skorupka (looking for new job) Lodz, Poland W dniu 06.05.2021 o 06:54, Wayne Bickerdike pisze: > Jo Monk said: > > > > Last I checked, PDUs are not sold by watts, but by volts/amps. > > Sure they are. Doesn't magically turn into power. A/C power consumption is > not that easily derived, unlike DC. I'll continue to use the laws of > physics. > > On Thu, May 6, 2021 at 1:41 AM Peter <[email protected]> wrote: > >> Thank you for the clarification. Now it help me to research further. >> >> On Wed, 5 May, 2021, 7:29 pm Billy Ashton, <[email protected]> wrote: >> >>> You also might need to consider if you have redundant power supplies or >>> redundant/diverse power sources. There will not be a single definition >>> of power consumption based on the number of units or even the number of >>> devices. A 12U rack used as a patch panel will have no consumption, but >>> a 12u UPS rack will have much more. >>> >>> ------ Original Message ------ >>> From: "Seymour J Metz" <[email protected]> >>> To: [email protected] >>> Sent: 5/5/2021 6:55:48 AM >>> Subject: Re: Datacentre Rack power clarification >>> >>>> That depends on the use profile. What equipment is in continuous use and >>> what is standby. Are you counting power for cooling? >>>> >>>> -- >>>> Shmuel (Seymour J.) Metz >>>> http://mason.gmu.edu/~smetz3 >>>> >>>> ________________________________________ >>>> From: IBM Mainframe Discussion List [[email protected]] on >> behalf >>> of Peter [[email protected]] >>>> Sent: Wednesday, May 5, 2021 2:25 AM >>>> To: [email protected] >>>> Subject: Datacentre Rack power clarification >>>> >>>> Hello >>>> >>>> Apology for posting a non mainframe questions here . >>>> >>>> Is there a way to determine the total power consumption of rack with 12u >>> as >>>> form factor ? >>>> >>>> I am sure some of them would have used a benchmark to design a solution >>> for >>>> any new server coming inside the data center floor. >>>> >>>> So any clue or your experience would help me to analyse further. >>>> >>>> Peter >>>> >>>> ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
