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Feed wire sizing to my garage

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ironhorse18

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#31
I haven't read every post word for word,,,, but what size of the entrance to your house? 200Amp? Do you have room for an additional 2 pole breaker in you main CB box? It is exactly like everyone says.................. size up.

steve

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abrace

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#32
I ran #2 THHN copper in conduit and protected it with a 125A breaker. #2 is good for 115A, but due to the next size up rule you can protect it with a 125A.

#2 is small enough it is still pretty easy to work with.
 

weaselfire

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#33
2/2/2/4 and 100 amp here as well. 70' you can hand trench quite easily in most soils, match electric code requirements for depth, wire size, etc.

In your 1/2" EMT you can run 4 #10 wires for 30 AMP 220. If that can meet your needs. Otherwise, you have to run new wire anyway. 12/3 with ground only gets you 20 amps. One circuit.

How you're getting EMT to hold up underground beats me.

Jeff
 

whitmore

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#35
Hi all, I'm looking for some advice. I'm looking to add power to my detached garage ...the run will be 70', it will power some lights (>2amps), a little old radio, and 1... a 1 HP vfd to power both my mill and lathe (240 3ph, 3/4 and 1/2 Hp respectively) I will also install 8 outlets.
.
If you want it up to code, it'll take a subpanel in the outbuilding with its own breakers. Your lights and
outlets will have 120V breakers, and the VFD a 240V breaker, so a stalled motor doesn't leave
you in the dark... Maybe there's already a breaker box there?

General guidelines: for a farm outbuilding, #8 wire for up to 50 feet, #6 wire minimum for anything
farther. Specifically, there's worksheets for totaling up loads (get _Wiring_Simplified_, H. P. Richter,
from the library if you want to see details), but probably the smallest subpanel (60A) and #6 wire
are going to be required.
 

Rustrp

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#36
I've read most of the comments and you've gotten some good info. There's a couple of points I will make. Safety is a factor when you attempt to stretch electricity beyond the laws that govern it. One comment I read from ewkearns had flashing red lights. You electrical service from which you will be pulling to your shop is the key. If you only have 100A then you may be stretching it. The electrical code dosen't say it's okay to it wire it like this, ________ (insert reason)? I know you stated you would be working when everything in the house is idle but on the occassion when it may be different? The second item is the 1 hp vfd. It would be good to look at the full load amps (FLA) of what you are running vs looking at HP. When electric motors run at less than or more than how they are rated it reduced their life, and this includes speed. Slowing a motor down or speeding it up by less than or more than 20% is detrimental.

With funds being a factor, my recommendation on pulling the wire would be to pull the correct size required. There's plenty of info on the net in regard to wire size, amperage, voltage drop, etc. You can use an undersized circuit breaker on the correctly sized wire, safely, but not an oversized breaker on incorrect wire size. I was taught to alway respect water, fire and electricity.
 

K3vyl

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#37
Run 2" pvc conduit out there and pull in wire for your present load. PVC conduit is cheap and digging is expensive. The 2" conduit could accommodate a 200 amp circuit in the future,should your needs increase.
 

ARKnack

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#38
One item that is never talked about in these thread is you voltage drop requirements. First I agree that the larger the wire the better, but better equals more expensive.
The original problem was the garage is approximately 70 feet. So assume a 100 foot run. The load requirements are lite, but allowing for future expansion lets assume 120 V @ 20 amps and 240 volt @ 30 amps. That amount of power will run most equipment. We can also assume a continuous load of 15 amps for lights and other small items. That mean a 120 V @ 35 amps. The National Electric code (NEC) recommends 3% voltage drop.

2017-03-14_10-28-13.jpg 2017-03-14_10-21-41.jpg

Doing a quick calculation, the recommended wire size is #8 for the 240V requirements but is #6 for the 120V needs. Note the multiplier show is incorrect, but calculations are correct.

Here are he calculations. Please note that the spread sheet isn't mine.

2017-03-14_10-34-40.jpg
 

abrace

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#39
One item that is never talked about in these thread is you voltage drop requirements. First I agree that the larger the wire the better, but better equals more expensive.
The original problem was the garage is approximately 70 feet. So assume a 100 foot run. The load requirements are lite, but allowing for future expansion lets assume 120 V @ 20 amps and 240 volt @ 30 amps. That amount of power will run most equipment. We can also assume a continuous load of 15 amps for lights and other small items. That mean a 120 V @ 35 amps. The National Electric code (NEC) recommends 3% voltage drop.
Voltage drop is an important consideration, but I am not sure I agree with your calculations. Assuming the OP has a standard 120/240 split phase service, then only the unbalanced current between the hot legs ends up travelling back on the neutral.

Using your example above, with 20A of 120V for receptacles and another 15A for lighting, assuming that the single pole breakers are connected to different poles in the panel (and any panel should have its 120V breakers balanced!) then you only have a 5A delta between the legs, and the neutral will end up carrying that 5A.

In other words, you would end up with 15A of 240V and only 5A of 120V in that example. Add in the 240V loads and you have a total of 45 amps of 220V and only 5A of 120V.

In most cases the feeds to outbuildings end up carrying very little current over the neutral. In big installs, it is allowed to undersize the neutral compared to ungrounded conductors for this reason.
 
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Rustrp

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#40
Voltage drop is an important consideration, but I am not sure I agree with your calculations. Assuming the OP has a standard 120/240 split phase service, then only the unbalanced current between the hot legs ends up travelling back on the neutral.

Using your example above, with 20A of 120V for receptacles and another 15A for lighting, assuming that the single pole breakers are connected to different poles in the panel (and any panel should have its 120V breakers balanced!) then you only have a 5A delta between the legs, and the neutral will end up carrying that 5A.

In other words, you would end up with 15A of 240V and only 5A of 120V in that example. Add in the 240V loads and you have a total of 45 amps of 220V and only 5A of 120V.

In most cases the feeds to outbuildings end up carrying very little current over the neutral. In big installs, it is allowed to undersize the neutral compared to ungrounded conductors for this reason.
Wondering what you mean by split phase service? I agree with you if this is 3 phase but I'm pretty sure I read single phase in the question being presented along with the need for the VFD.
 

ARKnack

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#41
Don't completely disagree with you abrace. I am making some assumptions of the load and not balancing it. I have seen that before. All 120 breakers on one side, 240v on the other. "Looks" pretty. The 240 volts does indicate #8 as an option. This was more to indicate that there is more to wire sizing than current carrying capacity. Myself, I ran 170 feet of #4 to my barn. Breaker size is 60 amp. Could go to 70 amps. More than enough power to run everything I need. Not even considering harmonics.
 

abrace

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#42
Wondering what you mean by split phase service? I agree with you if this is 3 phase but I'm pretty sure I read single phase in the question being presented along with the need for the VFD.
Split phase is your traditional residential electric service in the USA. Basically it is a single phase 240V transformer out at the pole with a center tap. That center tap is grounded and becomes your neutral. Any circuit you run that uses a single hot and the neutral only gets half the windings at the transformer and develops around 120V RMS. A circuit that uses both hots gives you the entire winding width and develops the full 240V.

In a properly balanced panel the neutral sits there and does nothing.

You can see this working by using an amp clamp in your panel. Clamp one hot and take the reading. Clamp the other hot, take that reading. Then clamp the neutral and take a reading. You will see that the neutral is exactly whatever the difference between the two hots are.

Most panels balance out pretty well on their own as long as you fill the panel in order with a 120/240V split phase system.
 

abrace

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#43
Don't completely disagree with you abrace. I am making some assumptions of the load and not balancing it. I have seen that before. All 120 breakers on one side, 240v on the other. "Looks" pretty. The 240 volts does indicate #8 as an option. This was more to indicate that there is more to wire sizing than current carrying capacity. Myself, I ran 170 feet of #4 to my barn. Breaker size is 60 amp. Could go to 70 amps. More than enough power to run everything I need. Not even considering harmonics.
Even in that model with 240's on one side and 120's on the other you should end up in pretty good shape. Where people get into trouble is using only odds or evens, or hook up multi wire branch circuits but have both breakers on the same pole...which is a violation of course, but what happens is the neutral ends up melting.

170 feet is a long run, you can go all the way to 90A (next size up rule) with #4 if you run THWN2 in pipe, but that is a long way and voltage drop would be a killer. Seems like a smart approach bumping up a size. A little bit bigger wire doesn't cost much more.
 

Rustrp

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#44
Split phase is your traditional residential electric service in the USA. Basically it is a single phase 240V transformer out at the pole with a center tap. That center tap is grounded and becomes your neutral. Any circuit you run that uses a single hot and the neutral only gets half the windings at the transformer and develops around 120V RMS. A circuit that uses both hots gives you the entire winding width and develops the full 240V.

In a properly balanced panel the neutral sits there and does nothing.

You can see this working by using an amp clamp in your panel. Clamp one hot and take the reading. Clamp the other hot, take that reading. Then clamp the neutral and take a reading. You will see that the neutral is exactly whatever the difference between the two hots are.

Most panels balance out pretty well on their own as long as you fill the panel in order with a 120/240V split phase system.
I understand the transformer arrangement, whether it's single of three phase. I'm just not sure how three phase applies to the original question asked. A balance single phase electrical panel seems more like an electricians myth than reality. Even if you have a single row of breakers down the middle or a double row of breakers in the panel the 220/240 breakers pull from the buss bar on the 110/120 side. It doesn't matter how you stack them in because the only difference between 220/240 and 110/120 breakers is the pin that trips both on the 220 breaker, and ohms law hasn't change.

If a panel has two rows then it's logical to even up the sides, top down, but the buss bars are rated much higher than the panel rating. If you want balance because it looks pretty, I'll give it a thumbs up.
 

abrace

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#45
Balancing the load is no myth. As long as your neutral is fully sized it doesn't matter.

However, my point was that voltage drop calculations were being done at 120V. Voltage drop calculations should be done for 240V when looking at a split single phase feeder, and not for 120V. I was simply trying to explain why, from a feeder's perspective, you don't need to do drop calculations at 120V.
 

Rustrp

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#46
Balancing the load is no myth. As long as your neutral is fully sized it doesn't matter.

However, my point was that voltage drop calculations were being done at 120V. Voltage drop calculations should be done for 240V when looking at a split single phase feeder, and not for 120V. I was simply trying to explain why, from a feeder's perspective, you don't need to do drop calculations at 120V.
If the feed was going to a sub-panel, yes you would add a neutral and the voltage drop would be calculated on the 240 feed. If the 240 was on a breaker inside the residence then there would only be two hot legs and a ground sized per NEC. Most wire size charts for amperage are based on 100' so voltage drop is already factored in. The reality of a need to balance a single phase panel is a myth. In reality the sub panel or main circuit breaker panel has been designed to compensate. You just can't unbalance a panel with one row of breakers and a person would need to work really hard to unbalance a panel with two rows by only using one one row and then if you look at the buss bars.............nah, can't be done.
 

abrace

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#47
If the feed was going to a sub-panel, yes you would add a neutral and the voltage drop would be calculated on the 240 feed.
Yes, a feeder to a outbuilding is what is being discussed.

The reality of a need to balance a single phase panel is a myth. In reality the sub panel or main circuit breaker panel has been designed to compensate.
I don't know what the sub panel/main breaker panel has to do with it. If you end up with a feeder to an outbuilding where you have 100A over hot A, and 20A over hot B, you wasted money on the feeder. That second hot is doing very little. You ran #3 out the building, when you could have run #6 if it was properly balanced.

You just can't unbalance a panel with one row of breakers and a person would need to work really hard to unbalance a panel with two rows by only using one one row and then if you look at the buss bars.............nah, can't be done.
Yes, in this specific case discussing needing 2 circuits correct. My statements were just an intent to educate on voltage drop calculations for single phase services, and why they should be done at 240V. We really arent disagreeing, but it seems you think we are. You have to try to unbalance a single phase panel, hence why, again, my suggestion is to do voltage drop calculations at 240V. If you fully read my posts you will see I said:

abrace said:
In most cases the feeds to outbuildings end up carrying very little current over the neutral.
abrace said:
Most panels balance out pretty well on their own as long as you fill the panel in order with a 120/240V split phase system.
abrace said:
Where people get into trouble is using only odds or evens
See? We seem to actually agree.
 

Rustrp

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#48
1). Why are you referring to the commercial power source as a split phase?
2). If this is a feeder then it would be supplying a sub-panel in the outbuilding, protected at the main circuit breaker panel with a circuit breaker of fused disconnect box.
3). Voltage drop is a factor but a very small one.
4). As a feeder the conductors would be three of the same size.
5). If this was a branch circuit (240 v) you would only have to hot legs and both the same size, plus the ground.
6). How can you provide a 240 v feeder with two differnet size conductors?
 

abrace

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#49
1). Why are you referring to the commercial power source as a split phase?
Because that is what residential 120V/240V service is commonly referred to as by many, myself included. Call it whatever you like.

Rustrp said:
2). If this is a feeder then it would be supplying a sub-panel in the outbuilding, protected at the main circuit breaker panel with a circuit breaker of fused disconnect box.
Correct, and code requires that for any more than a single circuit run to an outbuilding. You can't run 2 circuits to an outbuilding without putting in a feeder, panel, and ground rod. It is the only way to do it legally.

Rustrp said:
3). Voltage drop is a factor but a very small one.
Agreed, I wasn't the one raising voltage drop as a concern.

Rustrp said:
4). As a feeder the conductors would be three of the same size.
Most likely yes, although depending on the install the neutral could be smaller than the line conductors as long as it is properly calculated and meets requirements. In some cases, the neutral actually has to be bigger.

Rustrp said:
5). If this was a branch circuit (240 v) you would only have to hot legs and both the same size, plus the ground.
Correct again, but I think you misunderstood my post. I was saying of 100A on leg A and 20A on leg B then I need to size the feeder for 100A, meaning I would use #3 assuming conductors in pipe. If I rebalance the load by moving single pole breakers to swing 40A of load from leg A to leg B, then I would have 60A for each leg and now I would only have needed a 6AWG feeder. These problems tend to happen a lot more in commercial settings than residential. Again, as I said, things generally balance themselves.

I have run into 120V inverter based solar systems were balancing can be a problem, but that is an edge case nowadays.

In commercial settings with UPSs, balancing the 120V loads is critical. I actually had to do that in January. A UPS was slipping into soft bypass because it was overloaded all because one of the 2 legs was much hotter than the other. I moved some of the loads to the other leg, and the UPS went from over 100% utilization (where it goes into bypass) down to the low 90's.

It may not mean much to some, but this allows my company to defer the UPS upgrade to next year.

Rustrp said:
6). How can you provide a 240 v feeder with two differnet size conductors?
Who suggested that and how did you read that into my post? That said, see comment above about neutral. However, my previous post was not advocating using 2 different size conductors for the feeder. Just that if my example 100A/20A load had been properly calculated at the start, and balanced effectively, then the feeder could have been installed as a 6AWG feeder to begin with. Balancing the load properly most efficiently uses both line feeder conductors.

At this point I am done at this discussion. I feel that you are intentionally trying to twist my words and interpret what I am saying differently to try to make me out to look like an idiot. For what reason I do not know, but I am done with it. This forum isn't about that.
 

ewkearns

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#50
In the South, a few decades ago, some machine tools that were very "affordable" hit the used market..... These were machines coming out of regions in the north that were designed for 2-phase power (voltage differing by 90°)... these were 4-wire systems, though some of them were fed with 3 wires, a large diameter "common" wire and two smaller "hots." Some were, I am given to understand, even powered by two different generators. Those systems were split phase, but not single phase.

So, I think "split phase," in this sense, is probably a regional use of the word. Technically, it is correct as our "single phase" (voltage differing by 180°) power is derived by split voltages from a center tapped transformer. Single phase implies that the two legs are in phase and, are thus, additive (120V + 120V = 240V). Split phase, on the other hand, doesn't necessarily carry that distinction. Single phase is probably a better descriptor for that tingly stuff hiding behind the outlets in our homes and garages.


Purchasers of the above affordable machines quickly discovered that split phase motors (2-phase) don't run on polyphase (3-phase) power or single phase power.....
 

projectnut

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#51
We had our garage professionally rewired about 10 years ago. The electricians ran about 80' of 4 gauge 3 conductor wire to a 100 amp service. There are 2, 50 amp outlets, 2, 30 amp outlets, about a dozen 20 amp outlets around the perimeter and another half a dozen in the ceiling for lighting.
 

tq60

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#52
Balance panel is no myth.

First home had most all loads on one side and resulted in cooked panel parts.

Was older home with aluminum wire that had old and cruddy grease on connectors.

Meter would get hot to touch.

The theroy is simple and the neutral carries the non balanced loads if and when load is not balanced which is often in shop with lots of 120 volt equipment with large motors.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk
 

Rustrp

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#53
Balance panel is no myth.

First home had most all loads on one side and resulted in cooked panel parts.

Was older home with aluminum wire that had old and cruddy grease on connectors.

Meter would get hot to touch.

The theroy is simple and the neutral carries the non balanced loads if and when load is not balanced which is often in shop with lots of 120 volt equipment with large motors.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk
Aluminum wire and the result of using isn't as a good example for an unbalanced. There's a myriad of reasons for the failure or overheating but the first is using aluminum wire. Unfortunately an electrical service using aluminum wire requires maintenance. Aluminum wire manufacturers swear this isn't the case. Unfortunately the home owners doesn't know this. The "cruddy grease" Noalox, which is a nonconductive grease and zinc powder mix, is placed on the connection to prevent oxidation or corrosion caused by dissimilar metal. The expansion and contraction of aluminum wire due to heat causes loose connections, in electrical service panels.

"The theroy is simple and the neutral carries the non balanced loads if and when load is not balanced which is often in shop with lots of 120 volt equipment with large motors."

Yes, this would be/could be true if the service is 3-phase. What standard voltage range uses the common as a conductor?
 

magu

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#54
Thank you all for taking the time to comment, whether it was constructive or not. To the handful who read what I am trying to do and, maybe more importantly, why I am not doing more, and provided relevant feedback I appreciate it as that is what I was looking for by starting this thread.

On the note of technical discussion, I do plan to install a sub-panel, off of which I will run one 240V circuit and two 120V circuits. I have no idea how the emt is still there, but I can run a fishing tape through so I think I will be good, and yes it is emt not rigid. Anyone have a suggestion for a GFI breaker that won't fight with my VFD? While I don't intend to tell the township what I am doing (they would lose it if they came in for inspection and saw the knob and tube), I do want to do everything right. I am a mechanical engineer, so the NEC is far from my wheelhouse, but this is not the first time I have used it, I just like to consult with others when I'm outside my comfort zone.

I do not intend to come off as arogant or angry that someone disagrees with what I am doing, but consider this. The large majority of replies (aside from a recent patter of discussion about analysis methods which I don't mind a bit) simply statedin some form: "I used ____ (insert big wire/amp size), you should too" or "that won't be enough, just bite the bullet and install a big service" I would absolutely love to do that, I am not trying to skimp by to be cheap or lazy. I am trying to make what I have work so that I can use what equipment I have now, rather than let it wait for years. When you are responding to these types of threads, keep in mind your audience may not be in the same place in life so, while personal experience and recommendations are great, maybe try not to come off acting as though what you have done is the only way, it can be a bit discouraging. Also, I live in the hills outside of Pittsburgh, if anyone who attests to how quick and easy a trench would be to dig wants to show me, I would love the help. Don't bother bringing a shovel, we will start with matocks and move to digging irons. The trench will come in time, but it won't be a weekend project.

This is the one statement kin the thread which I actually find quite offensive:

Hate to point this out, but.... It's never a good idea to sit and think about how little you are going to do and then subtract from what you think you need for power in a shop. If you are not going to work in the shop, then forget about it. Put up a sky light to get some light in and start building shelves to store crap on. It's typically easier to begin building shelves in the middle of the floor so you can store as many things you will never use again on them. OR you can do it with the idea that you WILL be working out there. And buying equipment that will consume more power and build to accommodate it now.
Perhaps I am in a small majority that folks these days don't understand, but I am trying to take care of my family and my responsibilities. When all that is done, I try and sneak out to the garage and pursue my personal passion. Unfortunately, that meanes digging a trench and installing a large service comes after buying diapers, paying for daycare, sending my wife occasional flowers, doing dishes, updating the house, saving for someone elses college, and sitting on the floor building lego towers for a toddler (who has no appreciation for their architectual beauty) to knock down shortly before running off in a vain effort to catch the infinitely quicker dog. So no, I am not "sitting around thinking about how little I am going to do" I am working damn hard and knowing that my hobby needs to come absolutey last on the priority list.
 

Rustrp

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#55
Because that is what residential 120V/240V service is commonly referred to as by many, myself included. Call it whatever you like.


Correct, and code requires that for any more than a single circuit run to an outbuilding. You can't run 2 circuits to an outbuilding without putting in a feeder, panel, and ground rod. It is the only way to do it legally.


Agreed, I wasn't the one raising voltage drop as a concern.


Most likely yes, although depending on the install the neutral could be smaller than the line conductors as long as it is properly calculated and meets requirements. In some cases, the neutral actually has to be bigger.


Correct again, but I think you misunderstood my post. I was saying of 100A on leg A and 20A on leg B then I need to size the feeder for 100A, meaning I would use #3 assuming conductors in pipe. If I rebalance the load by moving single pole breakers to swing 40A of load from leg A to leg B, then I would have 60A for each leg and now I would only have needed a 6AWG feeder. These problems tend to happen a lot more in commercial settings than residential. Again, as I said, things generally balance themselves.

I have run into 120V inverter based solar systems were balancing can be a problem, but that is an edge case nowadays.

In commercial settings with UPSs, balancing the 120V loads is critical. I actually had to do that in January. A UPS was slipping into soft bypass because it was overloaded all because one of the 2 legs was much hotter than the other. I moved some of the loads to the other leg, and the UPS went from over 100% utilization (where it goes into bypass) down to the low 90's.

It may not mean much to some, but this allows my company to defer the UPS upgrade to next year.


Who suggested that and how did you read that into my post? That said, see comment above about neutral. However, my previous post was not advocating using 2 different size conductors for the feeder. Just that if my example 100A/20A load had been properly calculated at the start, and balanced effectively, then the feeder could have been installed as a 6AWG feeder to begin with. Balancing the load properly most efficiently uses both line feeder conductors.

At this point I am done at this discussion. I feel that you are intentionally trying to twist my words and interpret what I am saying differently to try to make me out to look like an idiot. For what reason I do not know, but I am done with it. This forum isn't about that.
I wasn't attempting to twist your words, I was attempting to untwist. Not only for myself but other readers. The original question presented was in regards to residential power so introducing an anecdotal commercial power issue with UPS being the example is a twist. I understand that geographics and demograpics play a large part in how we express ourselves.

As ewkearns stated in his last comment, split-phase was the forerunner of our current single phase supply. It's a 19th century power source that was used in a specific geographical area. Specific geographically because power lines to other parts of the country had not been strung yet. By the time power was supplied the issues with split-phase were out in front and transformers had changed or were in the process of change.

I'm no electrical engineer but I cringe when unproven electrical theory is presented as fact. It's easy to unbalance a 3-phase electrical service, but taking this and applying it to a residential application and telling/selling a home owner on an estimate to upgrade and rebalance their electrical service is ethically wrong. It does happen and it happens often. Yes, I do agree you were presenting voltage drop, but you were also presenting an electrical panel being out of balance based on circuit breaker placement, whereas in a single-phase service, it just isn't going to happen.

Another area with a twist is switching between feeder and branch circuit conductors. A 240v (single phase) branch ciruit requires two hot legs equally sized and a ground. A 240v (single phase) feeder requires three equally sized conductors comprised of two hot legs and a common.
 

Rustrp

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#56
Thank you all for taking the time to comment, whether it was constructive or not. To the handful who read what I am trying to do and, maybe more importantly, why I am not doing more, and provided relevant feedback I appreciate it as that is what I was looking for by starting this thread.

On the note of technical discussion, I do plan to install a sub-panel, off of which I will run one 240V circuit and two 120V circuits. I have no idea how the emt is still there, but I can run a fishing tape through so I think I will be good, and yes it is emt not rigid. Anyone have a suggestion for a GFI breaker that won't fight with my VFD? While I don't intend to tell the township what I am doing (they would lose it if they came in for inspection and saw the knob and tube), I do want to do everything right. I am a mechanical engineer, so the NEC is far from my wheelhouse, but this is not the first time I have used it, I just like to consult with others when I'm outside my comfort zone.

I do not intend to come off as arogant or angry that someone disagrees with what I am doing, but consider this. The large majority of replies (aside from a recent patter of discussion about analysis methods which I don't mind a bit) simply statedin some form: "I used ____ (insert big wire/amp size), you should too" or "that won't be enough, just bite the bullet and install a big service" I would absolutely love to do that, I am not trying to skimp by to be cheap or lazy. I am trying to make what I have work so that I can use what equipment I have now, rather than let it wait for years. When you are responding to these types of threads, keep in mind your audience may not be in the same place in life so, while personal experience and recommendations are great, maybe try not to come off acting as though what you have done is the only way, it can be a bit discouraging. Also, I live in the hills outside of Pittsburgh, if anyone who attests to how quick and easy a trench would be to dig wants to show me, I would love the help. Don't bother bringing a shovel, we will start with matocks and move to digging irons. The trench will come in time, but it won't be a weekend project.

This is the one statement kin the thread which I actually find quite offensive:



Perhaps I am in a small majority that folks these days don't understand, but I am trying to take care of my family and my responsibilities. When all that is done, I try and sneak out to the garage and pursue my personal passion. Unfortunately, that meanes digging a trench and installing a large service comes after buying diapers, paying for daycare, sending my wife occasional flowers, doing dishes, updating the house, saving for someone elses college, and sitting on the floor building lego towers for a toddler (who has no appreciation for their architectual beauty) to knock down shortly before running off in a vain effort to catch the infinitely quicker dog. So no, I am not "sitting around thinking about how little I am going to do" I am working damn hard and knowing that my hobby needs to come absolutey last on the priority list.
Thanks for the reply and chuckle regarding the trench...........I grew up in Florida and have visited Pennsylvania...I dig. :)

My comments to you were code and safety related. Code: What you pull conductors through is important and size is important. Let me address what you pull the conductors through. EMT isn't for direct burial and you may have EMT or it could be ridgid? The condition at this point is most important and it's a family matter. If you pull a conductor through damaged conduit you take a chance of skinning the conductor. Current flowing back through the damaged metal conduit (doesn't matter if it's EMT or Rigid) to ground doesn't care who's hand is in the sink full of water when they are electrocuted. Sidebar: This is one reason 110v plugs are polarized. It separated the hot leg from the **common and ground** which is mistaken sometimes by the novice handyman as unimportant, or based on when the common connects in the service panel.

The skinned wire may end up in an air space not touching anything. When the conduit floods with water....what then? The code is written for many reasons and safety is the primary one. -Russ
 

magu

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#57
Rustrp: I've worked on farms in Florida, I'll take digging in rocks over fire ants and mosquitoes any day.

I have an appreciation for code concerns so long as logic rules, and absolutely for safety. Gone are my days of working with live wires instead of walking to the breaker.

I can't say for sure what the conduit is under ground but it looks to be EMT when. It comes through the wall. It is also very old, so it might be none of the above. I've run a metal fish tape through it and not encountered any resistance of note, it also shows no signs of moisture intrusion and my basement has a spring continuously filling a cistern in the basement, the soil is very wet. The fact that there is no trace of water makes me think it is structurally intact, but I intend to run the new wires inside of Kevlar sleeving as an added measure. (Oh the fun things you can get for free when you work in weird industries)
 

Keith Foor

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#58
Well, if I offended you, don't think you are somehow in a small group of people. I offend a LOT of people.
That being said.
First question I would ask on this, why do you need to bury the cable to begin with? Is there a law that says it can't be done with areal cable?
Poles are reasonably cheap if needed and you could run areal wire out to the building and eliminate the trench and rigid pipe path.

Now for a bit of reason to do as much as you can instead of going with a minimum.
Say you feed it with the 3 runs of 12/2 that someone suggested. And then a killer deal on a larger lathe that needs 30 amps to run falls in your lap. 12 gauge wire is good for 20 amps not 30.
Point here is finding machines on the used market is sort of funny when you are on a budget. First the little table top 110 units are there. The Central Machinery stuff from harbor freight and similar low buck low quality gear. Then you get into the mid sized gear that people want new prices for (at least in my area of central Ohio and you aint far enough away that Ohioians aren't buying there) and it's 40 years old or better. But that's what everyone wants so they will pay the premium. Then you get into the bigger industrial gear that is heavy and hard to move and the price goes back down. But that stuff uses bigger motors and requires more power. But it's cheap to buy. Dragging something home to find out it can't be used sucks alot more than not having it at all. Trust me. I too know about being broke. Watching stuff rust away that I didn't have the money to invest in at the time and it sat and was ruined.

As far as how to do it on a shoestring.
First it doesn't ever happen overnight. It takes time to put together everything you need to do a project. Electrical systems don't come in a box that you buy and assemble. And that's actually a good thing, because you can buy your wire this week or month or whatever and maybe get some 4 square boxes to put outlets in and then next week get the outlets and faceplates. Once you have that stuff then it's the panel. and then later the breakers. do it slowly and it will come together.
The other thing to do is check the scrap yards for rolls of wire and long sections of cut wire.
As long as it's long enough and the correct gauge then it will work. Color isn't important. If it's all orange, so be it. You grab a roll of white, black, red and green tape and mark your conductors.

So don't be offended,,, be motivated to figure it out. Or be offended and let that motivate you. Yes, family comes before all else. Don't assume I don't know about that either.
 

tq60

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#59
That reminded me of something...

Buy one roll of wire!!!

We needed to put a sub panel in shop off of shop panel and cable distance was say 50 feet.

Buying by foot cable in 4 colors was one price but buying 500 foot roll of black was less...much less.

Used tape to mark each conductor and all is good and we have substantial amount left on roll for large load outlets for welders someday.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk
 

British Steel

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#60
Not exactly on topic but ..

I just changed out my workshop (cubby hole) lighting for led flurecesent fitting of 50w, it has a maintained live and a battery that will keep half the lights on for upto 3h if the power drops might be worth considering if your going to be working at night in the dark surrounded by spinny and sharp things :)

They have got a lot cheeper, and you can get a small bulk head light as a very cheep one juat to give enough light to find your way out.

Stuart
Same, but mine are fluorescent rescued from the skip when my (very eco-conscious) workplace went over to LED lighting - positioned to light the main breaker panel for house and shop as well as the spinny sharp things, cost me not a penny apart from the twin & earth to wire them in!

Dave H. (the other one)
 
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