Electrical wiring in home sizing help

Tbleppy

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Hello! I want to hardwire the inverter to a main breaker box and run circuits off of that as well as a subpanel for the downstairs. I have to buy all the supplies so I want to double check my plan for accuracy and soundness.

This is an off grid system running 1200 watts (12 100watt 12 volt panels hooked up 3s4p) connected to a 50amp circuit breaker runs to 40amp charge controller, goes through another 50amp breaker goes to 4 12volt 100ah LiFebo4 batteries hooked up 2s2p runs through a 150amp t class fuse and to a 24volt 2000 watt inverter.

Now Im going to get a main panel. I think it will need a 150amp double pole ac breaker at the top. Then 2 20amp breakers (1 for each bathroom upstairs), 2 more 20 amp circuits (1 for the fridge, 1 for the freezer), 1 15amp circuit for lighting in hallway and second bedroom, 1 15amp circuit for lighting in master bedroom which will light its bathroom and closet too, 1 15 amp circuit for kitchen lighting, 1 20 amp circuit for kitchen appliances, 1 15amp circuit for lighting in living room, dining room and downstairs stairwell.

The downstairs will need a subpanel containing 3 20amp circuits (1 for washer 1 for dryer 1 for dishwasher), 2 20amp circuits for garage, 1 20 amp circuit for bathroom. I think Ill need a 100amp breaker for subpanel.

im going to need romex 12 2 for all 20 amp wiring. Ill need 14 2 for all 15 amp wiring except in locations i need 2 switches to operate the same light fixture i will need to use 14 3.

The lengths I calculate for wiring will be the run through framing studs and overhead joists and back down through studs to reach the destination.

GFCI any wet locs(bath, kitchen) AFCI in bathroom too.

what wiring is needed to connect the subpanel and does that run from a breaker in main panel, if so what size?

does this sound accurate? Am i missing anything?
Thanks!
 

MisterSandals

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what wiring is needed to connect the subpanel and does that run from a breaker in main panel, if so what size?

does this sound accurate? Am i missing anything?
From my understanding of your system, you are creating distinct wiring circuits, separate from the grid/main circuits. Why do you want to tie this system (sub panels) into the main panel?
 

smoothJoey

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2000 ac watts / 120VAC = 16.666666667 ac amps

You want minimum 12 awg feeder wire and a 20 amp panel main breaker.
The breaker rating should not exceed the wire ampacity or your wire will be protecting your breaker and not the other way around.

Hang on.
A 2000 watt inverter will be 120VAC only.
Meaning no 240VAC split phase.
You will only be able to power one phase of the panel.
Unless you get into some jiggery pokery.
 
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Tbleppy

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From my understanding of your system, you are creating distinct wiring circuits, separate from the grid/main circuits. Why do you want to tie this system (sub panels) into the main panel?
i dont have a preference , i thought it had to be

are you saying i could have main panels

this is off grid and im really new to this

im making the plan and getting supplies

please inform me more of the way you are talking about
 

Tbleppy

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2000 ac watts / 120VAC = 16.666666667 ac amps

You want minimum 12 awg feeder wire and a 20 amp panel main breaker.
The breaker rating should not exceed the wire ampacity or your wire will be protecting your breaker and not the other way around.

Hang on.
A 2000 watt inverter will be 120VAC only.
Meaning no 240VAC split phase.
You will only be able to power one phase of the panel.
Unless you get into some jiggery pokery.
i plan to power a washer, dryer, mini fridge, freezer and dishwasher along with lighting and fans

everything is energy efficient

would twelve awg be appropriate for that

i need dedicated outlets for each of the appliances, these are portable appliances and not full size or standard

is this possible to do
 

smoothJoey

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i plan to power a washer, dryer, mini fridge, freezer and dishwasher along with lighting and fans

everything is energy efficient

would twelve awg be appropriate for that

i need dedicated outlets for each of the appliances, these are portable appliances and not full size or standard

is this possible to do
12 awg is appropriate for the feeder as your 120VAC inverter can only supply 16.66 amps flat out.
All that stuff you want to run is likely going to use stupid amounts of power.
If the dryer is electric you are dead in the water as it is a very high draw 240VAC appliance.
In the neighborhood of 24amps@240 VAC which is 5760 watts.

As described your scenario is far from workable.
 

MisterSandals

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this is off grid and im really new to this
Sorry, i misunderstood, i was thinking you were on the grid but not grid tied. My assumption was that you had grid power in your main and you wanted to add circuits to the main that were for just solar - mistake on my part.

For off grid, you could have a sub panel for each inverter. There are quite a few ways to do it.
 

smoothJoey

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@Tbleppy first question is...
Do you have any 240VAC loads?
If you do you will need a 120/240VAC split phase inverter and those start at ~4000 watts.
 
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Bud Martin

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Did you do the power consumption audit of what you will use for 24 Hours? Also worst case when you have minimum solar?
It looks like the system is too small to power all the loads.
 

Tbleppy

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dryer is electric you are dead in the water as it is a very high draw 240VAC appliance.
In the neighborhood of 24amps@240 VAC which is 5760 watts

This is the dryer. In its description it says "exhausted vent pipe included. Regular 3 prongs 120 Voltage can be plugged anywhere. 1300 Watts of motor rate which may take a little longer time to dry the clothes, but it saves the electricity bills."
 

smoothJoey

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This is the dryer. In its description it says "exhausted vent pipe included. Regular 3 prongs 120 Voltage can be plugged anywhere. 1300 Watts of motor rate which may take a little longer time to dry the clothes, but it saves the electricity bills."
While better than a regular dryer, yours will consume 65% of your inverter capacity on its own.
 

Tbleppy

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For off grid, you could have a sub panel for each inverter. There are quite a few ways to do it.
I just have one inverter hooked up right now. 24v 2000watt samlex pure sine wave. I have a 1000watt inverter not being used right now so i could incorporate that if neccessary.

My main goal was operating a freezer and then the fridge was my next priority. I know its just a small operation so if you have ideas about improvements, im open to it.

I need dedicated circuits and receptacles for the appliances. I am used to conserving and nothing needs to run together at the same time except fridge and freezer will run simultaneously with anything else.

There arent too many existing wires. Mainly just temporary ones were set up so its like an open slate. Can you possibly share some of the methods you like and/or the pros and cons?

I apologize for my lack of knowledge concerning this. A long time ago I never thought I could understand electricity. Now that I study it, I think it is fascinating. I think I grasp the basic concepts.

This forum really helped me with my solar array and system questions. I was hoping for some feedback on my interior wiring plan before i proceed with buying anything.

It is off grid. I want to wire 2 20amp outlets in kitchen (freezer/fridge). I want to wire 3 20amp outlets downstairs (washer, dryer, dishwasher) All appliances I mention are portable and energy efficient ones. They are not standard appliances with the typical expected load. In addition I want to add lighting in areas and outlets in areas so maybe 1 or 2 more 15amp circuits. Thats just the bare minimum of what I want to do.

Is that a reasonable plan? Is it difficult to add more later? Would I need a 150amp breaker for the main panel on/off? I plan on 20 amp AFCI breakers with GFCI either at breaker or outlet. Do you know which way is better from a function standpoint or from a cost standpoint? 12 2 NM for all 20amp circuits which will be wired through studs and overhead joists to reach their destination. 14 2 is adequate for 15amp circuits. 14 3 would be needed at any point I need one light fixture operable from different switches. Does this sound correct and/or doable in your opinion? Thanks!
 

Tbleppy

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While better than a regular dryer, yours will consume 65% of your inverter capacity on its own.
Ok, Im not stuck on the dryer. I can hang dry. What about everything else? It is off grid. I want to wire 2 20amp outlets in kitchen (freezer/fridge). I want to wire 3 20amp outlets downstairs (washer, dryer, dishwasher) All appliances I mention are portable and energy efficient ones. They are not standard appliances with the typical expected load. In addition I want to add lighting in areas and outlets in areas so maybe 1 or 2 more 15amp circuits. Thats just the bare minimum.

Is that possible minus the dryer? The rest of it though?

dishwasher:

washer:
ppx_yo_dt_b_asin_title_o08_s00?ie=UTF8&psc=1

inverter:

freezer:

fridge:

I appreciate any insight you can give me. Thank you.
 

smoothJoey

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I want to wire 2 20amp outlets in kitchen (freezer/fridge).
15 amps@120 volts = 1800 watts.
20 amps@120 volts = 2400 watts.

Are you really going to be running things that exceed the capacity of a 15amp circuit?

Since all your loads are 120VAC I suggest you get an ac/dc clamp meter and a line splitter to see the instantaneous and continuous load in watts that each appliance draws.

Then you can prioritize.

As for the 100 amp master breaker.
The 20 amp 12 awg wire that you would be landing on its terminals would melt its insulation off long long before it tripped.
I suggest you land the inverter on a 20 amp branch circuit and leave the main breaker disconnected.
 
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Tbleppy

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15 amps@120 volts = 1800 watts.
20 amps@120 volts = 2400 watts.

Are you really going to be running things that exceed the capacity of a 15amp circuit?

Since all your loads are 120VAC I suggest you get an ac/dc clamp meter and a line splitter to see the instantaneous and continuous load in watts that each appliance draws.

Then you can prioritize.

As for the 100 amp master breaker.
The 20 amp 12 awg wire that you would be landing on its terminals would melt its insulation off long long before it tripped.
I suggest you land the inverter on a 20 amp branch circuit and leave the main breaker disconnected.
Thanks for the advice. You are thinking 1 20 amp circuit will be adequate for my needs? It is possible. I didnt realize that.

The house is not wired very much right now. And its operating on a temporary system. I was wanting to get some permanent wires in place but do it gradually.

When hardwiring the inverter to an ac breaker box panel, should I use 12 awg like the same as on the dc side of it or should i use 12awg romex as in 12 2 or 12 3?

Do you recommend any particular breaker box or breakers? It should be single pole. Afci gcfi should be on there too right?
 

smoothJoey

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Thanks for the advice. You are thinking 1 20 amp circuit will be adequate for my needs?
I don't know how you got that from what I've posted.
It is possible. I didnt realize that.

The house is not wired very much right now. And its operating on a temporary system. I was wanting to get some permanent wires in place but do it gradually.

When hardwiring the inverter to an ac breaker box panel, should I use 12 awg like the same as on the dc side of it or should i use 12awg romex as in 12 2 or 12 3?

Do you recommend any particular breaker box or breakers? It should be single pole. Afci gcfi should be on there too right?
I think you should get an electrician.
 

Tbleppy

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I don't know how you got that from what I've posted.

I think you should get an electrician.
I guess I probably sound dense. Im just creating the plan. My husband was an electrician assistant. So I have to create the plan and get the supplies. If you can help me at all with my questions great. If not, thats fine too. If I misunderstood you it would be nice if you can clarify what you did mean. Thanks
 

smoothJoey

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I guess I probably sound dense. Im just creating the plan. My husband was an electrician assistant. So I have to create the plan and get the supplies. If you can help me at all with my questions great. If not, thats fine too. If I misunderstood you it would be nice if you can clarify what you did mean. Thanks
Ok I will re-read the thread and see what I can do.
If I have not said it before I am not an electrician.

Does your husband have a handle on grounding the system?
Is this system going to be inspected or insured?
 

smoothJoey

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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:
 
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