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Discussion Starter #1
I am looking to educate myself on what's involved with upgrading my home service from 200A to at least 400A (I live in the US) to run some very power hungry computer equipment. By my basic calculations, I am currently pulling 170+ amps continually (total watts are over 16,000).

Some questions I have:

1)what is involved in actually upgrading capacity? I have a 200A meter, I will be calling my electric supplier as I understand they replace/maintain those. So, I assume I ask them to put a 400A meter in? (I have a 400A panel currently).

2) what is the max continuous use of a 200A meter? I've learned I shouldn't run more than 18A continuous from a 20A breaker/outlet. Same goes for the meter?

3) the computer equipment can handle up to 240v, is it possible to somehow utilize 220/240v, thus reducing the amps each computer uses? (different plugs would be needed but that's not an issue).

4) Is my current situation considered unsafe?

I greatly appreciate any feedback
 

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Licensed Electrician
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I am looking to educate myself on what's involved with upgrading my home service from 200A to at least 400A (I live in the US) to run some very power hungry computer equipment. By my basic calculations, I am currently pulling 170+ amps continually (total watts are over 16,000).

16000 W is only 66.6 Amps @240V or 133.3 Amps @120V

Some questions I have:

1)what is involved in actually upgrading capacity? I have a 200A meter, I will be calling my electric supplier as I understand they replace/maintain those. So, I assume I ask them to put a 400A meter in? (I have a 400A panel currently).

POCO's don't maintain meter sockets. Why do you say you have a 400A panel? That would be VERY odd for a residential service.

2) what is the max continuous use of a 200A meter? I've learned I shouldn't run more than 18A continuous from a 20A breaker/outlet. Same goes for the meter?

A load calc would need to be done, but generically 160A.

3) the computer equipment can handle up to 240v, is it possible to somehow utilize 220/240v, thus reducing the amps each computer uses? (different plugs would be needed but that's not an issue).

You would still be pulling the same at either 120V or 240V. Say you have a 10A 120V load. If you put that same piece of equipment on a 240V circuit, you have 5A per phase of the service, but that still equates to 10A on your service...you are still billed for 10A by the POCO.

4) Is my current situation considered unsafe?

I don't think you are analyzing this correctly, so it's hard to say.

I greatly appreciate any feedback
Answers in red
 

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Discussion Starter #3 (Edited)
Answers in red
Thank you here are a few clarifications -

I am currently running about 21,000 watts continuous, not 16k (my math was off). I had an electrician come and put a bigger panel in, I'm pretty sure it's 400A but I can double check.

It looks like I'm running over the "safe" 160A currently (all the machines are running off 120v outlets). How "dangerous" is this?

I'm mainly trying to run as many machines as possible with my service, I am not sure if utilizing 240v allows me to do this. if it's just 6 to a half dozen, I won't pursue this option further.

Assuming I have a 400A panel, it looks like the "bottleneck" is the 200A meter. Is this correct, and can any licensed/competent electrician upgrade this?
 

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Master Electrician
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As far as power goes a watt is a watt whether it's 12 volts or 240 volts. Generally an upgrade requires larger service conductors from the utility service drop to the meter and larger conductors from the meter to the panel. It could be that your electrician may have up sized the conductors from the meter to the panel. Different POCOS have different requirements for 400 amp services. Some allow a 320 amp socket while others require a CT(current transformer) cabinet ahead of the meter.

Sorry kbuz, I overlooked your answer to # 3.
 

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Licensed Electrician
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Thank you here are a few clarifications -

I am currently running about 21,000 watts continuous, not 16k (my math was off). I had an electrician come and put a bigger panel in, I'm pretty sure it's 400A but I can double check.

It looks like I'm running over the "safe" 160A currently (all the machines are running off 120v outlets). How "dangerous" is this?

I'm mainly trying to run as many machines as possible with my service, I am not sure if utilizing 240v allows me to do this. if it's just 6 to a half dozen, I won't pursue this option further.

Assuming I have a 400A panel, it looks like the "bottleneck" is the 200A meter. Is this correct, and can any licensed/competent electrician upgrade this?
You are not comprehending how this works. You have 120/240V coming into the house. Even though you aren't running any 240V loads, you are utilizing both legs of the service.

If you total up everything electric in the home at 21 KW, you need to divide that by 240V not 120V.
 

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Licensed Electrician
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Take a picture of your panel with the door open and post it.
 

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Licensed Electrical Cont.
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It is HIGHLY doubtful that you have a 400A panel. No real electrician in his right mind would replace a 200A panel with a 400A without doing a service upgrade.

I also agree with Kbuz, you are not thinking this correctly. HOW are you measuring wattage? And amperage?

I also highly doubt you are taxing a 200A service with computer equipment in a home. Many folks have the misconception that even a room full of computers will overload a service.
Just exactly are you running? A server room? Laser printers?
"Some very power hungry computer equipment" is extremely vague.
 

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Licensed Electrical Cont.
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I am also under the strong opinion that a 400A upgrade is NOT a DIY project.
 

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Discussion Starter #10 (Edited)
You are not comprehending how this works. You have 120/240V coming into the house. Even though you aren't running any 240V loads, you are utilizing both legs of the service.

If you total up everything electric in the home at 21 KW, you need to divide that by 240V not 120V.
I only knew amps = watts/volts, beyond that I don't know much. you guys are helpful, thanks.

So as far as "capacity" is concerned, my 21 KW is only ~88 amps at the meter. So I have some wiggle room. I'll mention that these 21 KW are my computer equipment only- not AC, appliances, normal home usage.

I took a picture of the panel, it says 200A at the top, so that's that- I wish I paid more attention when the electrician was putting it in - I have 4 panels at this place, perhaps he was talking about all 4 totaling 400A (one panel feeds from this 200A panel, the other ones have their own line from the meter, if that makes sense).

To sum up, it looks like I don't need to upgrade, as I have room to grow. I was totaling watts used, dividing by 120, and thought that was it. Thanks again for the help.
 

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If you measured 88 amps at the meter, you do not have 21KW continuous.
The 88 amps was your entire house+computer load at the time it was taken.
 

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A "Handy Husband"
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I only knew amps = volts*watts, beyond that I don't know much

Watts = volts (times) amps


Amps = watts (divided by) volts


Volts = watts (divided by) amps
 

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Discussion Starter #14
It is HIGHLY doubtful that you have a 400A panel. No real electrician in his right mind would replace a 200A panel with a 400A without doing a service upgrade.

I also agree with Kbuz, you are not thinking this correctly. HOW are you measuring wattage? And amperage?

I also highly doubt you are taxing a 200A service with computer equipment in a home. Many folks have the misconception that even a room full of computers will overload a service.
Just exactly are you running? A server room? Laser printers?
"Some very power hungry computer equipment" is extremely vague.
I am measuring wattage by kill-a-watt type device, measured at the plug. So one unit is pulling ~2 KW at the wall, divided by 120 to get ~17 amps. All the computer equipment totaled is 21+ KW. This is just the computers - not accounting for any "normal" home use.
So if I'm understanding this right, my 21 KW are only using ~88 amps at the street? Which I don't quite understand because each unit on it's own is using say, 2000/120 = 17 amps at the wall, so 17 amps x 10 units = 170 amps pulling from the 200A panel (all the units are hooked up to the same panel). Again, this is my understanding of it.
I do not understand how the 240 volts is split into 120 once it reaches the house, and maybe that's where I'm getting things confused.

My concern was that I was reaching capacity or running things too close to their safe limits.
 

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Let's try this again. At the meter, you have 240 volt service, which consists of two 120 volt legs. So if you are pulling 88 amps at the meter, the total wattage is 88 * 240 = 21,120 or 21 KW. Each individual computer actually draws 17 amps at 120 volts, for a total of 17 * 120 = 2,040 watts = approximately 2 kw per computer.

As to how 240 gets split into two 120 volt legs, each leg is 120 volts leg to neutral. You can think of one leg as +120 volts and the other leg as -120 volts, so between the legs you get +120 - (-120) = 240 volts leg to leg. The panel is set up with two busbars, one for each leg, so the busbars are 240 volts bar to bar, or 120 volts bar to neutral. You get either 240 volts or 120 volts on your circuit based on the type of breaker you put in.
 

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Discussion Starter #18
If you measured 88 amps at the meter, you do not have 21KW continuous.
The 88 amps was your entire house+computer load at the time it was taken.
I did not measure anything at the meter - the only thing I have measured is each unit, and they pull 2 KW at the wall. I multiplied this out to get total watts used for the computers only. I could probably reverse calculate it, knowing my electric bill before these computers started running.

but that 88 amps at the meter was more a question, as my total (computer) use is again, 21 KW.

I guess it boils down to this - if I were to gauge my usage on a scale from "empty to full", where would I be right now, knowing I have a 200A meter, 200A panel, and 21 KW being pulled from that panel?
 

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Because you fail to realize your total 120 load is split between the 2 separate 120v legs of your service. So if you're using 100 amperes total, at 120 volts, your 200 amp service will see about 50 amperes on each 120v leg.
 
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