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Need Help Calculating System Amp Draw

Hi, I'm not sure if I'm posting this in the right place but I thought I'd try.

I know this is kind of a newbie question but I'm having trouble calculating the amp draw of my system. I'm running a recording rig and it's hard to tell what some of the gear is pulling. I know Amps are Watts/Volts but I'm confused about what actual wattage is being used (for example, my DAW has a power supply of 850W but the company that made the computer for me says that the way I'm using it, it's probably only pulling 500-600W). Some of the gear, like my monitors, say 230W on the back, but then online it says 90W, so I'm wondering if it's the same kind of thing where the power supply is higher than what's actually being used. I'm looking to add some hardware and don't want to overload the circuit.

Here's what I have, any help appreciated! Thank you.

Microphone Power Supply - 8.4W / 120V = 0.07 Amps

Lavry Black AD11 - 14W / 120V = .116 Amps

Mytek 192 ADC - I can't find any info but I'm guessing similar to the Lavry AD

Lavry DA10 - 0.1 Amps ?
    Voltage 90-264 VAC, Frequency 40-63Hz, Current 0.1A
    Fuse Rating 2.5A “Time Delay”

Computer - 850W Power Supply, probably just using up to 600W / 120V = 5 Amps

Lights - added up all the lightbulbs, it's about 0.75 Amps

KRK VXT6 Monitors - says 230W on the back? which would be 1.9 Amps each. The internet also says 120W and 90W in different places, so I'm confused.

Great River Preamp - says the fuse is 0.75A, not sure if that means it's using that much?

TV - says 1.8A on the back.

I'm wanting to add a compressor and a few additional preamps but it's only a 15A circuit.

Thanks!
 


 

128x128acar83
acar83's avatar
acar83 OP
13 posts
 

Haha I don't know if you're joking or not...

But yeah I just don't want to damage anything, this equipment is very expensive to fix, and I don't know much about the electrical stuff...

bigtwin's avatar
bigtwin
1,103 posts
 

Excessive draw will trip the breaker at the panel.  The only issue you would have with your equipment is sudden loss of power and that should not be a concern.  The same as turning off the power button any the piece itself.  The concern for your equipment is always a sudden power surge, like a lightening strike.  Your power conditioner is supposed to look after that unlikely event.  If you are running off standard household wiring, you are most likely maxed out with the 15 amp breaker on 14 AWG wire.  Are you able to run a dedicated circuit for your system?  

acar83's avatar
acar83 OP
13 posts
 

I probably could...we own the building, but I don’t know how much that would cost (the wiring for 20 amp). But if the consensus is that I’m not even close to 15 amps (or 12 or whatever the ceiling is) and the worst thing that could happen is the equipment just shuts off, then I’m not too concerned. If I were to hit the ceiling and everything keeps shutting off, then I’d be more inclined to pay for the 20 amp circuit...

Will lightning jump a circuit breaker? Normally I just flip the circuit in a storm, it’s too hard for me to get behind the desk and unplug from the wall. I mean, I can do it, it’s just a pain every time we have a storm. Was wondering if flipping the circuit actually does anything or if a surge from lightning would just jump it anyway, can’t remember what I’ve read...

imhififan's avatar
imhififan
2,102 posts
 

I'm using a Transparent Audio power conditioner

Plug a Kill-A-Watt to the wall outlet and plug your power conditioner to it, then you can monitoring the total ampere draw of all the equipment that plug into the power conditioner.

Most equipment only provide spec of maximum power consumption, not the normal usage.

If I put too much on the circuit, what's the worst that happens? It just trips the breaker? Or could it damage anything.

Yes, the circuit breaker will trip to prevent overloading the circuit.

 

erik_squires
15,630 posts
 

Add up the wattages on the back of the units.  For things like amplifiers and powered speakers this is the maximum power that the could draw, but with normal amps your actual usage is usually much lower. The 230W on the back would be used up only if you were using test tones at maximum output. 

Yes, you can get a new circuit, but you can't upgrade the breaker UNLESS you know you already have 12 gauge wiring everywhere.  If this is a circuit that is shared with lights I'm sure you do not.

Sounds like you may be better off getting a new additional circuit run.  I try to keep really noisy things like Ethernet switches and PC's outside of my clean power zone which is where my amps and DACs go.

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