Electrical wiring in home sizing help

Short_Shot

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Wow. This is going to go poorly if you think you can utilize only 2000w inverter and run large appliances.

The fact that you thought you needed 150a main breaker for 17 amps of 120vac tells me you definitely need a qualified expert to do an energy audit of your needs and expectations. It's clear you don't understand electricity in the slightest.

You definitely should not attempt to run single leg 120 to both sides of a breaker box as well.


Please get an professional in there before you attempt any of this and wind up burning your house down. It's really not worth the few dollars you will save attempting to DIY this.
 

Tbleppy

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Does your husband have a handle on grounding the system?
Is this system going to be inspected or insured?
yes, we have an 8 foot ground rod in the ground about 10 feet from the house and about 1 foot from the solar array. We have grounding cable connecting the array to the rod. We have cable hooking up the equipment inside to the rod as well attached to the inverter and dc breaker box. I understand its all got to be one path to ground with no loops. For the ac breaker box, that too will be connected and everything we wire will connect with a ground bus bar for that purpose as well.

we do plan on having it inspected and will do everything up to code. This will comply with the irc, nec code.
 

Tbleppy

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Please answer each of these questions.
number you answers so that I can easily map answers to questions.

q1 : why do you think you need a 150 amp double poll breaker?
a1:

q2: why would you do a sub panel for the downstairs?
a2:

q3: how many square feet is the house?
a3:

q4: why AFCI in the bathroom?
a4:

q5: why run 20amp branch circuits when your entire supply is 16.666666667 amps?
a5:

q6: do you have any loads that actually require a 20 amp circuit?
a6:
1) i thought 150amp breaker because the class t fuse i have before the inverter is 150amp.
2) i dont need a subpanel for downstairs. Initially i thought i did but thats really for a detached garage or a large kitchen or an addition to the house. I no longer think that.
3) the house is 1408 sqft upstairs and 708sqft downstairs but thats including the garage (which is 484sqft).
4) it should be gfci anywhere there is water like bathroom and kitchens. I was unsure about the afci.
5) I didnt know, thats why I am here. It sounds like i should run 15amp branch circuits since my entire supply is 16.66666667 amps.
6) I have no loads requiring the 20amp circuit.
 

smoothJoey

mumble...
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1) i thought 150amp breaker because the class t fuse i have before the inverter is 150amp.
The ac main breaker is in a completely different voltage domain from the dc side of the inverter.
Suggest you don't use the main breaker in the ac panel.
Since your inverter can only deliver 16.6 amps you should back feed a 20 amp branch breaker.
4) it should be gfci anywhere there is water like bathroom and kitchens. I was unsure about the afci.
AFCI was first mandated for bedrooms because arcs in appliance cords could ignite combustibles like bedding.
Not sure what the latest requirements are.
5) I didnt know, thats why I am here. It sounds like i should run 15amp branch circuits since my entire supply is 16.66666667 amps.
You may wish to run larger capacity branches is you ever intend to upgrade your inverter capacity.
12 awg wire costs more than 14 awg and the breaker may also cost slightly more.
The outlets may also cost slightly more but it won't hurt to do it if you have the requisite deep pockets.
But then if you did I doubt you would be trying to run a 1400 square foot house off of a 2000watts 120 volt inverter.
 

smoothJoey

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For the next step lets enumerate how many breakers you need.
Then find a panel to suffice.
Since you are runing 120VAC only are thinking of bridging the panel legs?
I suggest using this as a template
Code:
ac_distribution {
    upstairs {
        bedroom {
            15 amp afci
        }
        bathroom_1 {
            15 amp gfci
        }
    }
    downstairs {
        kitchen {
            15 amp gfci
            15 amp
            15 amp
        }
}
 

Tbleppy

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83
For the next step lets enumerate how many breakers you need.
Then find a panel to suffice.
Since you are runing 120VAC only are thinking of bridging the panel legs?
I suggest using this as a template
Code:
ac_distribution {
    upstairs {
        bedroom {
            15 amp afci
        }
        bathroom_1 {
            15 amp gfci
        }
    }
    downstairs {
        kitchen {
            15 amp gfci
            15 amp
            15 amp
        }
}
I really appreciate your advice. I was able to purchase the Homeline 100A 6 spaces 12 circuits 120/240 V~ Max 50/60Hz load center. It says purchase separately circuit breakers, ground bar kit:


i think that should work out just great! Thank you again. I just wanted some type of confirmation before proceeding. These are all my ideas and I take full responsibility for them. Thanks again!
 

smoothJoey

mumble...
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I really appreciate your advice. I was able to purchase the Homeline 100A 6 spaces 12 circuits 120/240 V~ Max 50/60Hz load center. It says purchase separately circuit breakers, ground bar kit:


i think that should work out just great! Thank you again. I just wanted some type of confirmation before proceeding. These are all my ideas and I take full responsibility for them. Thanks again!
You purchased a split phase panel and you have a single phase power source, are you going to bond the legs?
 

Hedges

I See Electromagnetic Fields!
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Messages
8,329
I really appreciate your advice. I was able to purchase the Homeline 100A 6 spaces 12 circuits 120/240 V~ Max 50/60Hz load center. It says purchase separately circuit breakers, ground bar kit:

That can work, but it is a small one. Sufficient for your small inverter today.
I would put in a larger panel so it doesn't need to be replaced if expanding later. Like one with 12 spaces, maybe 12 maybe 24 circuit.
This could also allow you to lock out the inverter and switch in a portable generator, for instance to run for a couple hours when you had a larger load. If you did have 240V loads run by generator, those usually take up 2 spaces, so 6 spaces would fill quickly.

The one you selected is surface mount, and for indoors. Some are for flush mount - they fit between studs, and cover fits neatly over a hole in sheetrock.

You may not need ground bar kit. If ground rod is wired to this panel, then that is where ground and neutral are joined, and a green screw through the neutral bar connects box to it. If ground/neutral connection is established elsewhere (usually if this is to be a sub panel in addition to another panel), then it would need a separate ground bar.

The following two are both flush mount. One is the more expensive QO model. They come with or without main breaker, which you don't need now but might use as part of a generator switch.


 

Tbleppy

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Messages
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You purchased a split phase panel and you have a single phase power source, are you going to bond the legs?
i can return the panel if its not going to work for me. Can you please explain bond the legs? We can do whatever works.
 

Tbleppy

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smoothJoey

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That makes sense. I should have more spaces. What about this one?



It appears to be single phase.

Looks like split phase to me.

My eyesight is poor but it looks to me like 2 parallel copper busbars in a hounds-tooth(interleaved) pattern.

Split phase power has 2 hots and a neutral.
One hot goes to each busbar.
Hot to hot = 240 VAC.
Each hot to neutral is 120VAC.
The interleaved pattern allows a double pole branch breaker connect to both busbars and provide 240VAC.

In order to energize both of those busbars from your single phase inverter, the busbars need to be connected together to make one big single phase busbar.

The 100 amp master double poll breaker at the top is not useful for your setup.

I suggested in a previous post that you enumerate your branch circuits by floor and room.
Seems you bypassed that step.
How many branch circuits do you need?
 
Last edited:

Hedges

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That one works too.
It looks like cover is not included, has to be purchased separately.

Whichever you buy (Homeline, QO, Siemens) you will be using breakers that are compatible. You can check availability and price. Usually that is the same brand, but for Homeline several other brands fit. I use QO rather than Homeline because it has higher quality copper bus (for models > 100A) and is used for commercial as well as residential. Siemens with copper bus appears to be similar quality.

Some panels say "12 spaces, 24 circuits", which means there are "tandem" breakers having two handles and two terminals that fit in one space. The Siemens you identified says 20 spaces 20 circuits, so only standard single breakers fit in each slot, but that's OK because 20 should be plenty for a cabin. You can also fit two pole breakers in two slots, for 240V loads (if you use a 120/240V source in the future, like a larger inverter or a generator.)

As Joey said, the 100A main breaker isn't needed for your application (at this time.) But it is included for the $82 price, so no problem. Buying a main breaker is often more expensive, so included with the purchase is good. In the future if you want the option of running a portable generator, it can connect to main breaker, inverter can connect to a branch circuit breaker, and an interlock between the two handles makes sure only one is on at a time.

Here is an example of such an interlock. Not sure if it is the correct one for this model panel or not. The price is stupid for a piece of sheetmetal, but the interlock is a useful feature and I finally broke down and paid the price (for one that fits my model.)

 

Hedges

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For wet location outlets (kitchen, bath, outdoors) you should have GFCI protection, shuts off power if it detects someone got a shock.
That can be done with either a GFCI outlet or GFCI breaker.

Here is a GFCI breaker from Siemens. Looks like it fits that style panel but I'm not certain.


Outlets. (Four outlets less than the price of one breaker. In my experience, the outlets fail and require replacement more often.)

 

smoothJoey

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For wet location outlets (kitchen, bath, outdoors) you should have GFCI protection, shuts off power if it detects someone got a shock.
That can be done with either a GFCI outlet or GFCI breaker.

Here is a GFCI breaker from Siemens. Looks like it fits that style panel but I'm not certain.


Outlets. (Four outlets less than the price of one breaker. In my experience, the outlets fail and require replacement more often.)


This plug on neutral gfci is cheaper and wiring will be neater.
 

Hedges

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This plug on neutral gfci is cheaper and wiring will be neater.

You're right. I saw the plug-on neutral GFCI breaker and skipped over it to link one with neutral pigtail, assuming the panel didn't have plug-on neutral. But looking back at the link OP gave, that ones does have plug-on neutral bus, as is mentioned in the listing.

OP: When A GFCI breaker is installed, neutral wire from circuit goes to breaker, and breaker has a neutral connection to inverter. That type of breaker used to be used only occasionally, and had a coiled wire that was wired to neutral busbar. New codes require [oops not GFCI] (correction: AFCI) for every outlet in a house, so rather than having twice as many neutral wires crisscrossing inside the breaker panel, "plug on neutral" was created. Snapping in the breaker makes that connection. You may or may not want/need to used GFCI for all circuits, but you should for wet-location circuits.
 
Last edited:

smoothJoey

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New codes require GFCI for every outlet in a house
Good to know.
If that is the case then the bedrooms at least will need dual function gfci/afci breakers.
I would also suggest dual function breakers where extension cords will be used, workshop or office for example.

The panel will fill up quick as afaik they don't make gfci tandem breakers.
 
Last edited:

Hedges

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Good to know.
If that is the case then at the bedrooms at least will need dual function gfci/afci breakers.
I would also suggest dual function breakers where extension cords will be used, workshop or office for example.

My bad. That's AFCI required for all outlets. GFCI for wet locations plus garage.
But including GFCI wherever AFCI is used should be fine. GFCI doesn't seem to be inconvenient. Some faulty equipment has electrical leakage current to ground and trips it, probably a sign if deterioration. I've replaced a garbage disposal for that reason.


May or may not be in effect in OP's location.
I've lived my whole life without having my house burn down due to arc fault. But it has happened to other people. My old mobile home with aluminum wiring did have overheated connections.

AFCI may or may not be a royal pain in the @$$ depending on whether it is prone to nuisance tripping. Brush type motors? Other electrical interference? To date, I haven't had AFCI in anything (except maybe PV inverters, but panels not on roof so not enabled.)

 

smoothJoey

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My bad. That's AFCI required for all outlets. GFCI for wet locations plus garage.


May or may not be in effect in OP's location.
I've lived my whole life without having my house burn down due to arc fault. But it has happened to other people. My old mobile home with aluminum wiring did have overheated connections.

AFCI may or may not be a royal pain in the @$$ depending on whether it is prone to nuisance tripping. Brush type motors? Other electrical interference? To date, I haven't had AFCI in anything (except maybe PV inverters, but panels not on roof so not enabled.)

I'm sure you know this but for the OP in the forum in general.
AFCI = arc fault circuit interrupter.
The AFCI breaker has a little signal processor in it that can detect the signature of an arc in a cord.
AFCI was first mandated for bedrooms to prevent all the combustibles(think bedding) from catching fire from an arc in a cord(think heating pad).

A power tool connected via extension cord lying on a floor covered in sawdust is the scenario I was thinking of.
 

Hedges

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GFCI = Ground Fault Circuit Interrupter.
Detects if 5 mA or more is flowing somewhere it shouldn't (like through a person into ground) by comparing current in hot line with current in neutral.
If detected, shuts of power fast enough to prevent injury.

If you're standing on a dry living room floor, not likely you would carry enough current to harm you or trip it. But if touching a faucet, standing in the tub, or working in the yard, a harmful shock is likely so GFCI needed.

GFCI is much less sophisticated and more reliable than AFCI, and has been around for decades.
I think I read 50,000 house fires in the US annually started by electrical problems. One loose wire nut or screw terminal is all it takes. AFCI protects against that.

And yeah, each AFCI (and/or GFCI) breaker costs as much as the entire load center panel. But it's all small potatoes compared to your entire electrical system, and your cabin/house. Besides, human safety is the primary reason, although codes came about by insurance industry trying to reduce losses.
 
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