Are you in the market for colocation? Calculating the amount of power you need or use is easier than you might think! Just remember the acronym “WAV” (Watts = Amps x Voltage). For example, take a standard full rack colocation cabinet, most come with either 20A or 30A circuits that use either 120V or 208/240V power. While you never want to place greater than an 80% load upon a circuit, you can quickly account for the amount of power you receive!

Example cabinet with 20A 208V circuit:

Watts = ?

Amperage = 20

Voltage = 208

This is simple to figure out, just grab a calculator and multiply the amperage by the voltage to obtain the watts! (20 x 208 = 4160) This means in the above example, you have:

– 4160w (total installed – not usable!)

– 4.16kW (just divide by 1000 to obtain the number of kilowatts!)3328w usable (80% of the total amount – just multiply total installed by 0.8!)

– 3.33kW usable power

Note, for most fire and safety codes, you should not put a live load of more than 80% upon a circuit at any given time. The power your servers and critical load (switches, routers, firewall appliances, etc.) use does fluctuate, so while it might idle at 1A, at times of high load (such as high utilization, power cycling, or initial boot after receiving power), that number can increase 1.5x, 2x or more.

Knowing the amount of power each of your servers draw is necessary to properly determine how much total power you need installed now, and how much you need to support your growth plans – in short, it’s key to providing you with infrastructure stability!

RackNerd staff can help you calculate your power requirements so you can select a proper colocation package to suit your needs. Simply contact us at sales@racknerd.com and we’ll give you a no-obligation quote that gives you the information you need to make an informed decision!