110v out of 220v ?

[cabinetman]

The problems arise when the job is done improperly( undersized, no deox is used). Just my well informed opinion.

Crokett would never do a job improperly.
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[crokett]

So you would be feeding a 100A panel from a 30A dryer circuit?
I would use 8 gauge copper wire for the feeder from the house. I used 10GA and I wish I used a heavier wire. Copper to aluminum connections are sometimes troublesome.


Tom on Marrowstone

Who me? No. The OP has a 30A dryer circuit. I have a 100A panel in my shop and will be installing a 100A breaker in my house panel and feeding it with 2-2-2 aluminum. Yes, I will probably never use the 100A but I've been stuck once before where I wired in what I needed and later wished I'd put in a bigger circuit.

Cabman, I know all about the drawbacks of aluminum vs copper and at twice the price copper is not worth it to me. Oh, and thanks for the compliment on me never doing jobs improperly. I appreciate it. That's why I am getting my house panel upgrade inspected and when I install the run to the shop that will get inspected as well. Just to make sure I do it properly.

[crokett]

No, I didn't miss Crash's post, and I hope his back feels better. I was referring to Hellrazor's advice.
.

Ah. ok, well then I will ask you what you asked Mike. Are you a master electrician, electrical contractor or electrical engineer?

In any case, his advice concurs with Crash's who I infer is a master electrician, and the inspector who I know is, not to mention what I already know about aluminum wiring. I am fully aware of the copper vs aluminum debate. I made it my business to know after I bought this house. My house has aluminum wiring from the meter to the main panel, from the main to the sub and it also is the wiring for another 90A circuit I have for the HVAC. I inspected them all myself and the other larger circuits in the main panel (30 and 40A) I rewired with copper, mostly for peace of mind. Thankfully the sub where the lights, etc are was copper already. Aluminum has its place. I would prefer copper, but not where the cost is prohibitive.

[woodturner]

You can find that out by reading my profile.

So I assume you mean to say you have no electrical experience or expertise, since your profile says you are a cabinetmaker?

Anyway, I am a licensed electrical engineer. It's incorrect to say copper is "better" - it has advantages for some applications, but the use of aluminum SE cable for service panels is almost universal in the US. It's almost impossible to find copper SEU.

[crokett]

Copper is better.
.

I can say I like copper "better". That's different than saying ignore the anti-aluminum crowd.
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Ah. Word games. You didn't say "I like copper better" you unequivocally stated it is superior. A statement you gave in context but now are changing it after being called on your qualifications to make it subsequent to you calling out another member on his qualifications.

You also don't play word games all that well. I assume you meant to say "that is different than saying ignore the pro-aluminum crowd." If I were ignoring the anti-aluminum crowd I would be ignoring those that think copper is superior, which of course is what I am doing already.

I'm done.

[Tom Slick]

[kbkreisler]

So if I understand correctly, a sub in a detached building since it requires its own ground rod anyway could be wired with two conductors and ground but no common while a sub in the same building would require 2 conductors, common and ground?

Crockett, as far as I know in a remote building you still need a total of 4 conductors (2 hot and a common) with ground. As well as seperate ground and common terminal strips. In addition you need a seperate ground rod.
The idea behind this is to reduce the potential for step current electrocutions. For example Without a ground rod at the sub if there were a condition where one of its feeders was damaged underground or an extension cord was in a puddle etc.. the current path would be toward the closest ground rod, your main service panel. If this rod is 300' away on the opposite side of the game your kids and the neighbor's kids are playing on cool morning with dew in the grass this could be devastating.

As far as aluminum feeders, when properly torqued and installed they are fine, Most homes already have them. The problem with aluminum wiring strung all over a house is that over time thermal expansion and contraction can make terminals loose. The "snugged up" 8x32 potmetal screws were more at fault than the aluminum wiring.

If you really want to worry about the feeders re-torque them annually, pick a day you wont forget like fathers day and make it one of the things on the to do list.

[master53yoda]

I'm going to step back in here because I'm probably the one that got the sidetrack started. I totally agree with Tom Slicks assessment of taking this away from the original question.

My background started as an industrial electrician, I have worked up to 4160 VAC on 1000 HP motors etc. the last ten years I worked as a electrical and mechanical system inspector. I have seen panels melted down because of aluminum wire that became loose or the anti corrosion Nolux was not properly used. I have also seen aluminum and copper conductors melted off when used in a split bolt connectors.

The code has addressed these problems and the only remaining issue with aluminum connections is making sure you use connectors or lugs that are rated for aluminum, not physically touching copper, proper tightening procedures, (torque to specifications) , and proper us of anti corrosion paste.
Copper works better at the connection point and for the same size wire generates less heat as in lower I2R losses. It is a better wire for running to motors as the start-up voltage drops are lower etc.
As in many things cost is the only factor that brings aluminum into use in wiring. that said I have no problems with aluminum being used as feeder conductors where the connections can be monitored.

My original concern was the installation of a very large capacity panel in a one man wood shop. Is the same logic that is sizing the shop panel to 80 amps requiring a change in the main service of the house from 120 amps to 200 amps???
The house as long as the some of the larger loads such as space heating, and water heating are not electric and it is smaller then 2500 ft doesn't need a 200 amp service. On the other hand if the house is larger then 4500 ft it probably needs a 400 amp service.
I hope this answers the questions.

It really bothers me when offense is taken when none was intended.
I have a saying I use when speaking with groups that I work with and that is that why would anyone ever allow someone enough power over them by taking offense at something they say, especially if they were trying to offend them. When we take offense our whole focus is shifted and controlled by the offender.
If they were not trying to offend them then the person taking offense is in the wrong to take offense, and need to apologize for taking it.
I personally refuse to take offense at anything that someone says because I will not give anyone that kind of power over me.

[crokett]

My original concern was the installation of a very large capacity panel in a one man wood shop. Is the same logic that is sizing the shop panel to 80 amps requiring a change in the main service of the house from 120 amps to 200 amps???

It really bothers me when offense is taken when none was intended.
I have a saying I use when speaking with groups that I work with and that is that why would anyone ever allow someone enough power over them by taking offense at something they say, especially if they were trying to offend them. When we take offense our whole focus is shifted and controlled by the offender.
If they were not trying to offend them then the person taking offense is in the wrong to take offense, and need to apologize for taking it.

First, I didn't take offense at anything you said. I took offense at what I deemed to be a direct comment on my character by another member.

Second, The 100A panel is already in the shop. It was there when I bought it. Do I need to run 100A service? Probably not but the cost for doing so isn't much greater than the cost of 60 or 80A. A few dollars price difference in the breaker and wire size. And as I said, I've run a circuit to an outbuilding before and then a few months later wished I'd run a larger one.

Third, my house already has 200A service. What it doesn't have is a main breaker shutoff. By code that means I can't put more than 6 breakers in my existing main and it is already full. So I can't add any more circuits be they 40A or 100A.

[master53yoda]

First,

Third, my house already has 200A service. What it doesn't have is a main breaker shutoff. By code that means I can't put more than 6 breakers in my existing main and it is already full. So I can't add any more circuits be they 40A or 100A.

code requirement is a max 6 mains in any service. You can drop one of the circuits that is currently in the mains in to the lower section of the panel the lower section is currently feed off of a 60 amp feeder that is typically one of the bottom breaker of the 6 mains. Typically the mains have a couple spare sections. most times the ac or pumps get stuck into the main sections but they can just as easily be feed from the subsection of the panel leaving you the ability to feed your shop from the mains.

My current house has a split bus panel like yours and I have my 30 amp AC unit , a 50 amp hot-tub, my 50 amp shop, the range and the clothes dryer running out of the mains with the swimming pool 30 amp 240/120 4 wire sub-panel running out of the lower buss section. this is totally within the NEC the max the main panel has ever pulled with all in operation was 130 amps total. I have no breaker tripping or heating problems. I also infrared scan my panels every six months and check torque every six months.

[crokett]

I don't -have- a lower section to the panel. I have 6 breaker slots. That is it. Believe me, I've looked at this every which way there is. I won't rehash the reasons in this thread but putting in a new panel is my best option.

[Mr__Bill]

Y'all think we will ever hear from yuri again?



Bill,
Have you ever heard of:
an aluminum smith?
polishing up the aluminum pots to hang on the wall for decoration?
aluminum bracelets?
aluminum bottom paint for your boat?
not worth an aluminum as an expression?
an aluminum head snake?
aluminum tone suntan lotion?
silver plated aluminum
or watched an old movie and heard E.G. Robinson say, 'you dirty aluminum take that...'
my work here is done....

[crokett]

I'm going to step back in here because I feel that cabinetman is getting a whole load of crap over a statement that he made that is 99% accurate.

Not from me. From me he is getting crap for a personal attack. But then there is also his questioning of others' credentials in an area that he has none. Maybe that is more why he is getting crap and less because of his original statement. What do you think?

[JR]

What do you think?

I think you should consider ceramic cable. It's all the rage with the superconductor crowd. There's the little matter of creating an environment operating at 1 or 2 degrees Kelvin, but I'm sure someone here can help with that.



JR

[woodturner]

lets face it copper is a far more forgiving conductor then aluminum will ever be.

As an electrical engineer, I disagree. For example, one application for aluminum wiring is in environments that are corrosive to copper. In those environments, copper wouldn't last a day.

In a previous statement i made from 30 years of wiring experience i have yet to see a copper connection fail that was sized right and any more then hand tight.

Limited anecdotal experience is insufficient to prove a point. I have certainly seen many failed copper connections due to improper torquing of the conductor. Not so common in residential wiring, since many people will apply enough torque when they "hand tighten" , but very common in industrial applications such as steel mills.

One of the reasons that AFCIs were introduced and now mandated by code was to address arcing due to improperly torqued copper connections. As you probably know (but others may not), a conventional breaker only trips due to sustained, significant overcurrent. So moderate overcurrent or intermittent overcurrent, such as from a lose connection, will not trip them. That's where the AFCI comes it - the AFCI (Arc Fault Circuit Interruptor) will trip on those intermittent arcing faults (which are perhaps the most common cause of house fires).