Estimate Power Consumption for Devices in Server Rack?

I'm new at this and have been asked to figure out how much power is being used by what we currently have in our server racks and also prepare for future expansion.

I'm thinking I could look at vendor information on power usage of the device?

Just wondering how others have done it.

thanks

***EDIT*** I'm also aware there is start-up power and running power too.

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Comments

Priston

I wouldn't guess by looking at numbers online. Are there any electrical meters anywhere? What type of outlets are you using? Are you running on 110V, 208V, or 220V? Do you have PDUs that tells you how many amps your pulling? Do you have an electrical bus? If so, does that tell you how many amps your pulling? What are the breaker sizes of the outlets, what are the breaker sizes of the electrical stuff upstream? Is there a facilities person that could help you if you don't know these answers?

You might just be able to talk to a facilities person and ask them how much power your using now in XYZ computer room and how much power you can use in the future.

TechGromit

Pretty much all equipment has voltage and amp draws on them, although, you may have to remove some removable power supplies to see this information. You just need to add up the draws for each device to get a total.

thomas_

Yes, vendor documentation usually has operating information on their hardware that includes information about power usage.

GSXR750K2

It may not be applicable in your situation, but including support costs such as inversion and cooling can give you a more accurate picture of total consumption (if the figures can be readily obtained).

Eliminating or consolidating devices will result in using less power than the devices themselves due to lower support requirements. Reducing consumption by 500 Watts may result in a cumulative reduction of 700 Watts when taking into account all of the factors.

bigdogz

Also remember that the servers take more juice on startup (cold boot or power on) and taper off.

You may want to verify with the vendor of the servers and get a meter to test. Vendor specs may vary. Some use max draws if the device is fully populated.

netsysllc

You could use something like UPS Selector | Dell UPS to get a rough estimate

pevangel

Vendor docs usually have detailed information about power consumption. Some will even break it down depending on what cards/modules you have running. I've had to spec out power requirements (AC and DC) for large projects and a 208V/30A circuit is usually a safe bet for a rack. Get two drops for redundancy.

TechGromit

bigdogz wrote: »

Also remember that the servers take more juice on startup (cold boot or power on) and taper off.

I always use the max draw rating when calculating draws. I never want to be in the situation when I calculate a running draw and that one extra piece of equipment puts me over and i trip the circuit. Also as a rule of thumb, never exceed 80% rating of the circuit. So your max draw on a 20 AMP circuit would be 16 AMPS.