240 Volt from Service Panel A to Panel B?

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eagle470

Occasional Visitor
I'm looking at running an additional breaker box in my basement for my unraid, ubiquiti and other gear in a comm. closet of sorts. Eventually this will turn into my office.

I want to run 240 Volt power for my gear. DO I need to run 240 from one side to the other, or can I run 120 and then draw 240 on the other side? Does anyone have any links on how this would be done?

Edit Added for detail:

I'm doing a bit of my own work and I've made sure I have complied with gauge and safety requirements. My second breaker box is mounted on an external concrete wall.

I have 50' of untrimmed 6/3 wire (got it off the shelf for $168, so it was cheaper than the 6/2 stuff.) This is in metal flex conduit and strung through my basement trusses. It's a direct run from Panel A to Panel B.

I only need about 50-60 amps of server at location B. I'm using SIEMENS gear and have 12/2 and 12/3 in metal flex to run behind my insulation on the concrete wall.

What I'm trying to figure out is how I get 240 Volts to Panel B.

DO I run a single 50 AMP breaker for the main at panel B and use 120 and then draw 240? This seems wrong.

DO I instead install the joined, dual pole 50 amp breaker on one of the child slots and then run/mark that as the main breaker? This makes the most sense, but I'm an IT guy trying to learn power, not an EE or Electrician (though I'm thinking about going for an EE.)
 
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L&LD

Part of the Furniture
You can't run 120V and get 240 at the destination.

Use a professional electrician in your area and don't go near (dangerous) equipment you don't fully understand.
 

eagle470

Occasional Visitor
You can't run 120V and get 240 at the destination.

Use a professional electrician in your area and don't go near (dangerous) equipment you don't fully understand.
It's only dangerous if you don't ask the right questions and use proper PPE. I've had many discussions with Electricians that have been more than positive. I'm trying to do this on the cheap as I'm running low on funds to get the project done.
 

L&LD

Part of the Furniture
It continues to be dangerous when you don't know which questions to ask (ignorance is the danger here).

Keep saving until you can get this done right (by a professional). Your conversations with your electricians haven't been very fruitful if you're asking questions like this (still).

PPE doesn't save you, from what you don't know is dangerous, to begin with. Rather, the contrary, I would suggest.

If you really must do this yourself, a home improvement site may be better suited than these forums. YouTube is also a good bet for these types of 'guides' you're asking/looking for.
 

L&LD

Part of the Furniture
The price of a quality converter is more than what an electrician should charge to do it properly (from the main service panel).

And, it would only 'convert' the equivalent of one outlet at maximum Watts too.
 

faria

Senior Member

faria

Senior Member
The price of a quality converter is more than what an electrician should charge to do it properly (from the main service panel).

And, it would only 'convert' the equivalent of one outlet at maximum Watts too.
we need more info from the op, in order to give him an accurate response,
where does he live?
is the house only 120v and can be wired to 240 to his current needs?
the max watts power he needs for the project ?
Where im from, a plugin industrial 110v to 240v Converter Step up 3kva 2 X 16 Amp is cheaper than an electrician working a coupe of hours.
 

L&LD

Part of the Furniture
He wants a 'B' service panel. That suggests to me more than one or two 1,500W outlets.

There is no house today with 'only' 120V. Three-phase power guarantees that. Dryers, stoves, garages all need more than 120V.
 

TheLostSwede

Senior Member

faria

Senior Member
That's simply not true. I live in a 110V country and we have 220V for several appliances. It's wired up and fused separately though, but it's perfectly possible to get 220/240V in a 110/120V country. Our place was only 110V when we moved in. No expensive step-up converter needed.
I see , a double wired house! United states comes to mind:D in that case all you need to do is wire from 240 to to the place you need it.

if you have any 240v sockets nearby its fairly easy to set up, if you don't then an electrician can run a cable/sockets to where you need .
 

L&LD

Part of the Furniture
Your post 12 doesn't change any of my recommendations.

Unless you can get the city to power off your Panel A, you're working on a live circuit. Pay the electrician to do the job he knows to do and keep yourself and your family alive instead.
 

faria

Senior Member
I advise you to heed the advice as @L&LD posted above.

NEVER EVER, EVER MIX VOLTAGES. I get you are trying to save money by doing it yourself but what you proposed is not wiring a extra plug!
 

L&LD

Part of the Furniture
The principles are simple. The real-world implementation isn't.

All you need to understand is that what has been described so far. Panels are live (always). Don't fool around them, even if all the breakers are off, the Panels are still 'hot'.

Get 3 or 4 estimates, go with the person you trusted the most (not necessarily the one with the lowest price).

You still haven't given any information that was asked of you. What will be powered by Panel 'B'? What is the total wattage of the expected equipment attached to those breakers? Note that you will need a permit too to do this. And the main Panel 'A' may not be rated at enough AMPS to provide for that second Panel. This will cost more if a direct connection to 'outside' power is required.

Avoid trusting any electricians that may offer to do this type of work without proper permits and certification/inspection. Save money. But be safe first (and always).

A breaker will break the circuit it controls (if wired correctly. And, just like a (light) switch that switches the neutral but still seems 'safe' as the light turns on/off, Panels can be wired wrong, and dangerously).

Panels are also wired directly to the Power Meter with no bypass (without city approval). If you need to connect to 'outside' power instead of your Panel 'A', you are facing the brute force of the entire electrical capacity for your neighborhood/transformer. Go use your favorite search engine for further information (you have many keywords to use now), but I hope you know that this isn't something to be taken on lightly.

Here's a freebie...

Three-phase electric power - Wikipedia

Even though it doesn't seem like you've tried any of the recommendations so far.
 
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eagle470

Occasional Visitor
I’m not doing anything crazy. I’m going to run a small set of systems, mostly for my homelab. I have a 3kVA UPS I might bring online, but I expect the total draw to be less than 12 amps at peak. I’ll also set up some lights and 20 amp 120v outlets on this. I don’t take this lightly. This has been a slow process. I’m way over rated on my cable, I’m not taking this lightly, I just dont think this is as hard to do as you say.

yes it’s dangerous, but so is riding a horse or standing near a turning PTO.

there are lots of ways to die, but I dont Plan on this being mine.
I did talk to some electricians at lowes and they said they would gladly come check my work and do the final tie in for me. I’m probably going to take them up on that.
 

L&LD

Part of the Furniture
You haven't done anything crazy (yet). I sincerely wish you all the best.

You don't wake up one day and decide to ride a horse. Someone shows you. Wiring up your own panel is much more dangerous than you seem to think.

What's a 'turning PTO'?

There are no electricians at Lowes. Sales Associates. Pick up your phone and call a few actual, working electricians out to your place for an estimate and ask to see their up-to-date tickets. You may be surprised by what they say.

Again, hope you stay safe and keep your family safe too.
 

eagle470

Occasional Visitor
I do have a great idea of the risks here. I’m just not putting them down for you to read.
Powe Take Off, it’s the spinning part that operates many farm implements. It runs things like a hay baler, thresher, post digger or a disc mower.

if you aren’t careful to stay away it WILL catch your clothes and you’ll get wound around it until your thrown free (in pieces) or the remenants of your carcass just thump around until someone finds you hours later.

I’m not doing this in a vacuum and I don’t take this lightly.

it’s a little like doing your brakes wrong. It can kill you, but you have to be super careless and not any clue what your doing.

the fact that I’m here (and several other places) asking questions, means I’m not a moron.

my brother is an ME and my dad has done this before.
 

L&LD

Part of the Furniture
Thanks for the PTO explanation. :)

You don't have to convince me though.
 

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