Power Consumption

I just want to make sure I have my PA run the safe way. I don’t want to trip any breakers playing live. In a large are we use 4 sw218 subs. I run one pair in stereo on a p7000 Yamaha and the other pair off of another P7000 Yamaha. I use 4 main they are Peavey Sp2. I run those in stereo off of two amps as well. We run 4 floor monitors off of 2 amps that stay bridged. I want to run the monitor amps on a separate circuit from my main pa I know, but do you guys think I will have any power issues running this on 110 power?? I have always used 220 and a break out box but here lately seems nobody has 220 available on stage. Just want to make sure I can do it the safest way possible. Keep in mind we also run 2 guitar amps and a bass amp as well. I am open to any suggestions. Thanks you all in advance!!!

I don’t do live sound, and I don’t know all the specifications for those amps, so I can’t give you a real simple answer.

However, it’s the total amount of amperage (current) you are drawing versus what the outlet circuits are rated for that is what you need to be concerned about.

In general, 220 volt circuits are usually designed for higher current ratings (more amperage), however, there are high current 110-120 volt circuits as well.  The standard wall outlets in your home are usually only rated for 15 amps of current.  So, a 120 volt residential outlet with a 15 amp breaker can produce a total of 1800 watts of power before tripping the breaker.

High power equipment that needs more than 15 amp circuits will have a special plug on them that won’t fit into a standard residential circuit.  For example, I have a couple of 20 Amp Balanced Power Transformers in my studio and I had electricians run two 20 amp dedicated circuits for them (they still are 120 volt circuits).

I’m guessing that any decent kind of live venue should have at least 20 amp circuits, possibly even higher, but be certain to check with the people at the venues first to see what each outlet can handle, and which outlets are on different circuits/breakers.

A 20 amp circuit can handle a total of  2400 watts of power on a 120 volt circuit.

The formula is simple:  Power (in watts) equals voltage times current (in amps).

So, figure out what the current rating is for each 120 volt circuit you’ll be using, and then you’ll know how many watts each circuit can handle.

Then, look at your power amps to figure out how many watts each one of them draws and do some math to figure out how many you can plug into each circuit.  The power ratings on the amps are usually just when you are driving them at full maximum capacity, so as long as you don’t go over the maximum wattage each circuit can handle, you should be just fine, even with everything cranked.

Hope that helps!

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