Power delivery is the most critical part of any data center upgrade. Top tier data centers provide multiple power feeds into their facilities, which most likely isn’t a financially viable option for a data center located in an office building.

You’re first step is ensuring the electrical services to your building are capable of supplying the amount of power necessary for your needs, while giving you room to grow your infrastructure.

Determine your Power Requirements

How much power you require is the single most important part of your data center upgrade.  Everything that follows is based off of this calculation…no pressure, right?

If you have a UPS or metered PDUs you can collect the amps/wattage currently in use. If you don’t have metered power distribution equipment you will have to do one of the following.

Option 1: Estimate power consumption based on equipment make and model.  Most manufacturers have power calculators that allow you to build your infrastructure online to discover the total wattage.

Option 2: Have an electrician come in and clamp one of the phases of your power. They can then average the usage going to your IT infrastructure.

If estimation is the only means you have available, remember not to use the rated sticker readings. The sticker on a power supply gives the potential maximum output and not the nominal wattage the device uses. Often the supply is capable of providing twice the power required to run the equipment. If you go purely off these numbers, you will overbuild your power infrastructure…CFOs tend to frown on this.

Calculating Wattage

If only amperage information is available to you, then you’ll need to calculate wattage on your own. Wattage is expressed as Amps x Volts = Watts.

If your supplied voltage is 120V and you’re using a total of 40 amps, it would be: 40 x 120 = 4,800 watts (often represented as 4.8 kilowatts or kW).

If your supplied voltage is 208V single-phase and you’re using a total of 40 amps, it would be: 40 x 208 = 8.3 kW.

Once you calculate required wattage, you can size your UPS equipment, remember that isn’t the entire IT load. If you’re building an application-specific environment, you also need to consider cooling requirements. HVAC equipment isn’t run on UPS, but it will be connected to your generator. This will be a key consideration when determining generator requirements.

Download The Essential Guide to Upgrading Your Data Center for an extensive guide.