Capacity vs Quantity. 15a vs 20a circuits

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jeb101
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Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Wed Dec 05, 2018 10:59 am

I am about to order and wire my basement from scratch, and of course to make things a little more difficult, I am starting to run low on breaker space, and want to save money in the end. I am not sure what would be best in terms of outlets. Have a few more outlets on a 20a circuit, or have more breakers and use 15a circuits. Odds are, I'd have to start looking at space savers for the panel if I were to throw a bunch of 15's in there.


In the basement I would anticipate the highest load as this is where I would have (at times) several high powered PC's (Max 8) which can draw anywhere from 4-600w on full load, each in the living room, so I was considering having 20a circuits there, and have 15 in the bedroom.

If I am right, I can do 1800w on a 15a circuit and 2400w on a 20a circuit, so technically, 3 or 4 PC's depending on breaker.

Using the 6ft per outlet rule, ignoring obstructions and whatnot, I have ~138ft of exterior walls, so 23 outlets required. Which would bring me to around that number with walls and obstructions taken into account.

If I want to be a cheap a**, what is the cheapest way to go around doing this? The main room will have all of the load, and likely have 1 breaker for the bedroom, and the bathroom will have it's own 20a, as my GF's hair drier needs the power of a small sun to use.

Do I get a ton of 14/2 and space savers + cheaper 15a outlets, or am I better off getting fewer 20a breakers and more expensive outlets? I already need 12/2 wire for the bathroom, and the cost difference seems to drop a bit once you get above 30m. ~65$ more expensive for a 150m spool of 12/2 vs 14/2, but then outlet and breaker pricing is also a bit more also.

In your opinion, what would be my best bet? Capacity or Quantity? I also understand I'm trying to have my cake and eat it too... :lol:

Cheers!


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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by emtnut » Wed Dec 05, 2018 8:33 pm

jeb101 wrote:
Wed Dec 05, 2018 10:59 am
Have a few more outlets on a 20a circuit, or have more breakers and use 15a circuits. Odds are, I'd have to start looking at space savers for the panel if I were to throw a bunch of 15's in there.

I would have (at times) several high powered PC's (Max 8) which can draw anywhere from 4-600w on full load If I am right, I can do 1800w on a 15a circuit and 2400w on a 20a circuit

Using the 6ft per outlet rule, ignoring obstructions and whatnot, I have ~138ft of exterior walls, so 23 outlets required.
I'll give you a bit of info, cause I don't know where you are (consider adding your location to your profile as codes vary by region)

"space savers" aka tandems, there is nothing wrong with using them as long as the panel accepts them.
15A is 1440w and 20A is 1920watts for your PCs. Any continuous load needs to be at 80% circuit capacity.

It's not 6' per receptacle, it's 12'

12 or 14 awg options are location specific.
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Wed Dec 05, 2018 9:51 pm

I'll give you a bit of info, cause I don't know where you are (consider adding your location to your profile as codes vary by region)
Done! Thanks, never thought of that. I'm on the east coast of Canada.
"space savers" aka tandems, there is nothing wrong with using them as long as the panel accepts them.
I confirmed that it does take tandem breakers, Square D panel from last year, 40 breaker 80 circuit. I made sure it was compatible before considering this, last thing I want to do is burn down my house, or kill somebody.
15A is 1440w and 20A is 1920watts for your PCs. Any continuous load needs to be at 80% circuit capacity.
It's not 6' per receptacle, it's 12'
Those are really good points, don't want to max it out completely. Of course 12ft makes a LOT more sense, I completely misunderstood what was written. every 6ft your house would be absolutely littered with outlets. :oops: :lol:
12 or 14 awg options are location specific.
12awg is a must for 20a in my area for sure, I checked with the old code book I found, and asked the city inspector for municipal laws, but nothing other than code they say.


Thanks!!

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Aaron
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by Aaron » Wed Dec 05, 2018 9:59 pm

The six foot rule is just saying that at no point along a wall should there be more than 6 feet to the nearest receptacle. So if they are spaced a max of 12 feet apart, then the middle of that span still satisfies the rule.

I generally place recepts near doors, windows, and corners of a room. Then with the remaining usable wall space, rather than every 12 feet, I make it more like 10 feet.

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Thu Dec 06, 2018 9:24 am

Aaron wrote:
Wed Dec 05, 2018 9:59 pm
The six foot rule is just saying that at no point along a wall should there be more than 6 feet to the nearest receptacle. So if they are spaced a max of 12 feet apart, then the middle of that span still satisfies the rule.

I generally place recepts near doors, windows, and corners of a room. Then with the remaining usable wall space, rather than every 12 feet, I make it more like 10 feet.
haha yeah... after reading that code again it makes a whole lot more sense, and makes the price difference between 15 and 20a cheaper, as I need 30% less outlets / breakers.

Every 10ft sounds good to me, and around windows and stuff is a terrific idea!

I think I'm going to do 60/40 between 15 and 20a plugs. How many outlets would you put on a circuit? 3 or 4? I'd stick to that with both 20 and 15a.

Cheers

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Aaron
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by Aaron » Thu Dec 06, 2018 10:18 am

Well Canadian electric code specifies that you can have up to 12 outlets per circuit (outlets are defined as receptacles, lights, or any junction box for that matter where a tap into the circuit can be made).

In the US there is no such limit.

All it boils down to is what potential load you will have on the circuit. The 12 outlet rule on a 15 amp circuit is perfectly fine for bedrooms, usually, as there is rarely a continuous 1440 watt load on the circuit. Think of alarm clocks, lamps, phone chargers, etc. Modern LED bulbs draw as little as 9 watts. An alarm clock is probably the same.

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Thu Dec 06, 2018 11:31 am

Aaron wrote:
Thu Dec 06, 2018 10:18 am
Well Canadian electric code specifies that you can have up to 12 outlets per circuit (outlets are defined as receptacles, lights, or any junction box for that matter where a tap into the circuit can be made).

In the US there is no such limit.

All it boils down to is what potential load you will have on the circuit. The 12 outlet rule on a 15 amp circuit is perfectly fine for bedrooms, usually, as there is rarely a continuous 1440 watt load on the circuit. Think of alarm clocks, lamps, phone chargers, etc. Modern LED bulbs draw as little as 9 watts. An alarm clock is probably the same.

That is great info, thank you. I heard of the 12 outlet rule, and was planning on using a single breaker for the bedroom plugs , and likely a single breaker for all the basement lights, I don't want to add lights and plugs on the same circuit, but since it'll all be LED or similar, I will be FAR from maxing out a circuit. Just gotta be creative on keeping it at 12 or less, junction boxes counting will be tough also, but I think is going to be easy enough to get around.

Things like my AV equipment is going to have it's own breaker to ensure a clean source, likely use tandem for those and just have 2 circuits going to a 2 gang box and wire each independently, ensuring there is no noise on the line for the audio gear.

I am getting a much better idea on how to do this now. Basement lights get one, bathroom fan + light gets one (if I can?), 2 gang 20a for bathroom (gfci), my desk area is going to be either a 2 gang 20, or, if I can legally, single gang on each side of the stud??? Simply for space.

Laundry / utility room will be the trickiest one, as I need to future proof it for eventually installing a central vac (20a), air exchanger (15a), upgrade the washing machine to a 20a, and have one more 20a breaker in there for when I want to use high amp devices, and probably a 15 also.

Having outlets every 10ft will likely be my go to, depending on how many there will actually be, will determine how far I stretch or segment the circuit.

Are split outlets still a thing this modern day? I'd be tempted to do so, but I also understand the risk behind it, esp if working on an outlet and you forget to kill the other, but less of an issue with a tandem, as it's still on the same breaker more or less, just remember to kill both sides, or tie them together, but kind of defeats the purpose by doing that.

I know there are loads of questions here, and I appreciate this so much. This is my first project of this type, and unfortunately with the hidden damages and whatnot we had huge expenses that cut into the "hire a pro" funds and it fell on my shoulders do to myself, then pay the light inspection fees. So far I've had no issues getting the OK by the inspectors. Find the strictest code you can find, and go beyond it. Do it once, do it right.

Cheers!

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by Aaron » Thu Dec 06, 2018 1:17 pm

jeb101 wrote:
Thu Dec 06, 2018 11:31 am
That is great info, thank you. I heard of the 12 outlet rule, and was planning on using a single breaker for the bedroom plugs , and likely a single breaker for all the basement lights, I don't want to add lights and plugs on the same circuit, but since it'll all be LED or similar, I will be FAR from maxing out a circuit. Just gotta be creative on keeping it at 12 or less, junction boxes counting will be tough also, but I think is going to be easy enough to get around.
Lighting is generally low load, think of rooms where the light is turned off. You can put the lighting for an entire house on just 2 or 3 circuits. For your basement you could probably just tap from an existing circuit.
jeb101 wrote:
Thu Dec 06, 2018 11:31 am
Things like my AV equipment is going to have it's own breaker to ensure a clean source, likely use tandem for those and just have 2 circuits going to a 2 gang box and wire each independently, ensuring there is no noise on the line for the audio gear.
A neighbor friend of mine is a guitarist and he said that all his audio amps, mixers, and stuff needs to be on the same 120V leg, otherwise he gets ground loops and noise. The legs are usually even/odd breaker spaces in the panel... one leg for even breakers, one for odd. So if you use a tandem breaker, both circuits on the tandem will be on the same leg.

You would also do well to install isolated ground receptacles, just to ensure the receptacle has an interrupted, straight ground path to the source (the main panel's ground). These orange-colored receptacles have mounting yokes that do not have ground continuity with the ground screw on the receptacle. But then if you are using NM cable you should also sleeve the bare copper ground wire with green heat-shrink tubing on both ends of the circuit (so it cannot make contact with other grounds, particularly in metal boxes).
jeb101 wrote:
Thu Dec 06, 2018 11:31 am
I am getting a much better idea on how to do this now. Basement lights get one, bathroom fan + light gets one (if I can?), 2 gang 20a for bathroom (gfci), my desk area is going to be either a 2 gang 20, or, if I can legally, single gang on each side of the stud??? Simply for space.
If your bathroom ceiling or vanity light and/or fan are not within a meter of a water source, you can just power those with a general lighting circuit from the rest of the house. I suggest you use a dedicated 20 amp GFCI receptacle, though. Or even just 15 amp should suffice.

Yes, you can put boxes on each side of the stud. No problem.
jeb101 wrote:
Thu Dec 06, 2018 11:31 am
Laundry / utility room will be the trickiest one, as I need to future proof it for eventually installing a central vac (20a), air exchanger (15a), upgrade the washing machine to a 20a, and have one more 20a breaker in there for when I want to use high amp devices, and probably a 15 also.
Usually a washer and dryer can share a circuit, and I don't think it requires 20 amps.

As for future-proofing, well, you can always run the cables to boxes, tuck the cable into the box, and just leave the other end stubbed by the electrical panel. Use a permanent black marker to write where the cable goes, and then you can terminate it sometime in the future. Then you can erect drywall and not worry about it at the moment if you are thinking you may need to upgrade your panel down the road (or put in a sub panel).

You said you have a 40-space panel, that is a LOT of breakers. I assume you have a 200 amp main coming in.
jeb101 wrote:
Thu Dec 06, 2018 11:31 am
Having outlets every 10ft will likely be my go to, depending on how many there will actually be, will determine how far I stretch or segment the circuit.

Are split outlets still a thing this modern day? I'd be tempted to do so, but I also understand the risk behind it, esp if working on an outlet and you forget to kill the other, but less of an issue with a tandem, as it's still on the same breaker more or less, just remember to kill both sides, or tie them together, but kind of defeats the purpose by doing that.
Usually receptacles are only split when one side is switched. This was common when rooms did not have ceiling lights. You'd flip a switch and a lamp plugged into the switched receptacle would turn on. This circuit may or may not be the same circuit as the non-switched receptacle(s), but it usually is as the receptacle that is split will just have one neutral terminated to it that is not split.

I guess it was also common in Canada where receptacles would be split in the kitchen, so one circuit was on top and the other on the bottom. The idea was that you would statistically balance the load on two circuits depending on which plugin was chosen for an appliance. This is not really done anymore since code requires two dedicated 20 amp circuits for the kitchen.
jeb101 wrote:
Thu Dec 06, 2018 11:31 am
I know there are loads of questions here, and I appreciate this so much. This is my first project of this type, and unfortunately with the hidden damages and whatnot we had huge expenses that cut into the "hire a pro" funds and it fell on my shoulders do to myself, then pay the light inspection fees. So far I've had no issues getting the OK by the inspectors. Find the strictest code you can find, and go beyond it. Do it once, do it right.
If your basement is livable space (finished), code may require you to install ACFI breakers. Those are unfortunately not cheap, and I'm also not sure whether they exist in a tandem configuration.

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Thu Dec 06, 2018 2:22 pm

Aaron wrote:
Thu Dec 06, 2018 1:17 pm
Lighting is generally low load, think of rooms where the light is turned off. You can put the lighting for an entire house on just 2 or 3 circuits. For your basement you could probably just tap from an existing circuit.
That is a good idea for simply tapping into an existing circuit for the basement, I will investigate a little more, or just throw it on a tandem if I don't have space.

Aaron wrote:
Thu Dec 06, 2018 1:17 pm
A neighbor friend of mine is a guitarist and he said that all his audio amps, mixers, and stuff needs to be on the same 120V leg, otherwise he gets ground loops and noise. The legs are usually even/odd breaker spaces in the panel... one leg for even breakers, one for odd. So if you use a tandem breaker, both circuits on the tandem will be on the same leg.

You would also do well to install isolated ground receptacles, just to ensure the receptacle has an interrupted, straight ground path to the source (the main panel's ground). These orange-colored receptacles have mounting yokes that do not have ground continuity with the ground screw on the receptacle. But then if you are using NM cable you should also sleeve the bare copper ground wire with green heat-shrink tubing on both ends of the circuit (so it cannot make contact with other grounds, particularly in metal boxes).

Darn, this is getting interesting, I will do some more reading tonight as it could be an interesting option, but may be simpler to do a dedicated circuit. I will have to see and decide from there.
Aaron wrote:
Thu Dec 06, 2018 1:17 pm
If your bathroom ceiling or vanity light and/or fan are not within a meter of a water source, you can just power those with a general lighting circuit from the rest of the house. I suggest you use a dedicated 20 amp GFCI receptacle, though. Or even just 15 amp should suffice.

Yes, you can put boxes on each side of the stud. No problem.
I will ensure that the fan circuit and lights are not within a meter when I design the bathroom, should be simple enough, and easier. 20a for sure in the bathroom, as my GF's new hair drier is a pro model and says it can use a 15a plug, but basically maxes it out and you will pop it with little extra load.

Having an outlet on both sides of the stud is awesome, as it will allow for larger plugs without covering up something else.

Aaron wrote:
Thu Dec 06, 2018 1:17 pm
Usually a washer and dryer can share a circuit, and I don't think it requires 20 amps.

As for future-proofing, well, you can always run the cables to boxes, tuck the cable into the box, and just leave the other end stubbed by the electrical panel. Use a permanent black marker to write where the cable goes, and then you can terminate it sometime in the future. Then you can erect drywall and not worry about it at the moment if you are thinking you may need to upgrade your panel down the road (or put in a sub panel).

You said you have a 40-space panel, that is a LOT of breakers. I assume you have a 200 amp main coming in.
From what I could see, you need 15a for a washing machine, but 20a if you have washer + gas dryer on the same circuit, but I use electric, so this won't be an issue. Either way though, it'll be on a dedicated circuit. Doesn't seem like GFCI is needed either.
Aaron wrote:
Thu Dec 06, 2018 1:17 pm
Usually receptacles are only split when one side is switched. This was common when rooms did not have ceiling lights. You'd flip a switch and a lamp plugged into the switched receptacle would turn on. This circuit may or may not be the same circuit as the non-switched receptacle(s), but it usually is as the receptacle that is split will just have one neutral terminated to it that is not split.

I guess it was also common in Canada where receptacles would be split in the kitchen, so one circuit was on top and the other on the bottom. The idea was that you would statistically balance the load on two circuits depending on which plugin was chosen for an appliance. This is not really done anymore since code requires two dedicated 20 amp circuits for the kitchen.
I think I won't be splitting outlets, and just segment it out some more, easier to wire, less issues for the future etc.

Kitchen is all 15a, as it predates the code and I am grandfathered in, but I did tap into the source, and split them into their own circuit, and switch it to GFCI where I had normal plugs like 12 inches from the sink...
Aaron wrote:
Thu Dec 06, 2018 1:17 pm
If your basement is livable space (finished), code may require you to install ACFI breakers. Those are unfortunately not cheap, and I'm also not sure whether they exist in a tandem configuration.
I took a look, and it seems that it's only living spaces, so bedrooms below grade require one, but non living spaces can be normal breakers. So the bedroom plugs will get it's fancy 100$ AFCI breaker. I believe lights in the bedroom are fine on their own circuit, if not, I'll throw the lights on there also to satisfy the inspector.


Thanks again!

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by emtnut » Thu Dec 06, 2018 9:00 pm

You're coming along quite well ! Just wanted to point out a few things.

Since you're limited to 12 devices (junction boxes don't count) , there is usually no advantage to going to a 20A circuit. Possibly the circuit on your PCs would be a good idea, depending on how many you put on a circuit. If you do load up that circuit with PCs, then don't add any other recepts to that circuit.

If you go with 20A for the bathroom, you can't feed the lighting. Lighting HAS to be on 15A circuit.

Sorry for the bad news, but you need AFCIs down there.

If you dedicate the lighting (no recepts on it) , you can load up to the maximum rating of all the fixtures, so you can usually have lots more than just 12 devices... especially if you are using LED lighting. (Add up the fixture ratings, not the bulb rating)
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by Aaron » Thu Dec 06, 2018 10:52 pm

You guys in Canada have that nice lighting-only loophole for not needing AFCI. Enjoy it while it lasts!

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Fri Dec 07, 2018 7:34 am

emtnut wrote:
Thu Dec 06, 2018 9:00 pm

Sorry for the bad news, but you need AFCIs down there.
Well that's the start of an expensive Friday morning! :lol:

I guess I'll have to re-organize the upstairs breakers with space savers and make room for these afci breakers. Do these still have the heat issues when you put them all next to each other? I'd have a heck of a time re-ordering the whole thing to stagger them if so.

As for the lines, I'm likely going to do a single wall with 20a, then my desk and bathroom with 20a also as it's next to each other, the rest with 20's. AFCI breakers are literally the same price for 15 or 20a, cause they know that ~80-100$ a pop is enough...



Edit: I was making a BOM and also realizing panel space is going to be tight... Do air exchangers / HRV's require their own circuit? I believe every one I've seen do, and I was going to, but I was curious as the info seems a little all over for this..

Also curious on how kosher it would be to add a junction box and to power 2 heaters / thermostats from the same breaker? Basically, I'd remove the dedicated bathroom heater circuit, and throw it on the 1500w bedroom with the bathroom 750w by splitting the source. With AFCI my 40 circuit is vanishing uber quick.





Thanks for the info!
Cheers

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by Shannon » Fri Dec 07, 2018 8:29 am

To make room you could move existing Non ACFI or GFCI circuits to tandems in the panel. These existing circuits legally do not need to changed to AFCI as they were existing and you have not changed the circuit.
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Fri Dec 07, 2018 8:47 am

Shannon wrote:
Fri Dec 07, 2018 8:29 am
To make room you could move existing Non ACFI or GFCI circuits to tandems in the panel. These existing circuits legally do not need to changed to AFCI as they were existing and you have not changed the circuit.
Could I put tandem breakers in the kitchen to save space? I have 4 breakers that could free up 2 if I swap to tandem, they are all 4 GCFI. No AFCI breakers anywhere else in the house at the moment.

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Fri Dec 07, 2018 11:14 am

Decided to simply go all 20a for the basement, minus a few circuits, as I calculated, with a 10% overhead, 74m, I didn't want to risk having to go out this weekend at the hardware store vs a supplier for more cable, so I ordered a 150m spool, and cost will be ~80$ more if I were to do 14/2. Breakers are basically the same price.

So in a 980sq ft basement I'm going to put in:

150m 12/2 yellow
75m 14/2
30m 14/3 for some lights

Breakers add up quick when you need to add dedicated circuits.

- HRV gets it's own 15a
- Central vac gets it's own 20a

Then I'm going overkill for the rest.

20ft wall gets 4 outlets @ 20a
6-8 outlets on back + side wall @ 20a
PC desk 2 gang + 1-2 more outlets @ 20a
Bathroom @ 20a
Bedroom @ 15a
Lights @ 15a
TV / entertainment wall 6 outlet, 2 gang + high plug @ 15a
upstairs entertainment cabinet @ 2 gang 15a

If pop a breaker I am doing something horribly wrong...

Since I need AFCI, I am replacing 16 breakers to tandems, none of them are constant / high load to ensure heat is not an issue, as they tend to be toasty according to what I am reading. Any high load breakers get their own.

I am also combining 2 heaters into a single circuit to save on breaker space also, as I have a 2500, a 1500, and a 750 on their own 2p20's, so I will combine the 750 and 1500 together and use the other 20a for basement heat.


I'm excited to start the project, this will be a great weekend!

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by emtnut » Fri Dec 07, 2018 11:24 am

Be careful if you're changing the breakers that currently feed the kitchen.

If they are MWBCs (ie, the 2 breakers are fed from 14/3 cable), then you need to make sure that each hot of the new breaker is on a separate phase. If not, you can overload/overheat the shared neutral.

There could be an issue with the baseboard heaters as well (any 240V load, being changed to tandems)
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Fri Dec 07, 2018 1:12 pm

emtnut wrote:
Fri Dec 07, 2018 11:24 am
Be careful if you're changing the breakers that currently feed the kitchen.

If they are MWBCs (ie, the 2 breakers are fed from 14/3 cable), then you need to make sure that each hot of the new breaker is on a separate phase. If not, you can overload/overheat the shared neutral.

There could be an issue with the baseboard heaters as well (any 240V load, being changed to tandems)
The kitchen was actually changed a few weeks back to their own circuits, so they are all 14/2's, turns out they powered the WHOLE kitchen through the fridge plug, which was charred when I took it out (and replaced), and drilled straight down. So the Fridge, Nuke, and 4 plugs are all on their own circuits running 14/2 as they were mostly already existing, and grandfathered in. No more jumping from plug to plug in there.

The 240v breakers are not going to be tandem at all, the only thing I'll be doing is going from 1500w to 2250w by splitting the feed in two via junction box right at the panel, allowing me to use the recovered breaker in the basement.

Question for heat generation by tandem breakers, would it be OK to have lets say microwave and fridge on the same tandem?

Would 2 high load devices running each at ~1500w for 5h (unlikely scenario) on one tandem surrounded by breakers be an issue?

I just want to make sure i'm not creating a heat problem, because unfortunately those AFCI breakers take up loads of room, and they don't come tandem that I could see.

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by emtnut » Fri Dec 07, 2018 5:22 pm

jeb101 wrote:
Fri Dec 07, 2018 1:12 pm
Question for heat generation by tandem breakers, would it be OK to have lets say microwave and fridge on the same tandem?

Would 2 high load devices running each at ~1500w for 5h (unlikely scenario) on one tandem surrounded by breakers be an issue?

I just want to make sure i'm not creating a heat problem, because unfortunately those AFCI breakers take up loads of room, and they don't come tandem that I could see.
I haven't come across any problems with similar situations.

Generally, all you would consider is not putting all high load in one spot in the panel.
ie, usually range and dryer on opposite sides, and just don't put for example, a lot of heavy loads (4 or 5 of them) bunched together.

Also, you mentioned earlier of heat in the AFCI breakers. I haven't heard of any problems having many AFCI breakers together in the panel.

Hope that helps
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by emtnut » Fri Dec 07, 2018 5:27 pm

jeb101 wrote:
Fri Dec 07, 2018 7:34 am
emtnut wrote:
Thu Dec 06, 2018 9:00 pm
Sorry for the bad news, but you need AFCIs down there.
Well that's the start of an expensive Friday morning! :lol:
You have the option of running AC cable to the first AFCI receptacle, and feeding the circuit from there.
Some guys run a short 6" of AC to a blank face AFCI, then feed the circuit from there. It's a bit more labor, but saves a few bucks on the AFCI breaker.
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by Aaron » Fri Dec 07, 2018 5:38 pm

emtnut wrote:
Fri Dec 07, 2018 5:27 pm
Some guys run a short 6" of AC to a blank face AFCI, then feed the circuit from there. It's a bit more labor, but saves a few bucks on the AFCI breaker.
Ha! That is ridiculous.

Now I'm thinking you could just have a 9-gang box chase-nippled to the panel, with 9 gangs of faceless AFCIs.

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Shannon
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by Shannon » Fri Dec 07, 2018 6:52 pm

You stated that you changed the circuits in the kitchen a few weeks ago to 14/2 circuits and stated they were grand fathered. Technically if you changed them they should have been brought up to current code IMO?
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Sat Dec 08, 2018 7:20 am

Shannon wrote:
Fri Dec 07, 2018 6:52 pm
You stated that you changed the circuits in the kitchen a few weeks ago to 14/2 circuits and stated they were grand fathered. Technically if you changed them they should have been brought up to current code IMO?
I guess changed wasn't the right word, they were segmented. Basically the feed was going from the attic to the basement (weird I know) then back up from a few junction boxes split into 5, so I kept the original wires in the exterior walls and threw them on their own circuit. There was one that I re-ran a new wire, but kept that at 15a because I had no 12awg and 20a breakers, that I should of changed for sure though.

May not be the best way, but absolutely better than what it was previously, as they used an outlet as a feed. The fridge outlet had 2 hots, one on top and bottom of the outlet then spliced from the outlet again to the next plugs. The outlet was melting slowly over time. They are all on their own independent line now. The electrician who helped me swap from the panel said he's never seen anything quite like it.

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by emtnut » Sat Dec 08, 2018 1:29 pm

Aaron wrote:
Fri Dec 07, 2018 5:38 pm
emtnut wrote:
Fri Dec 07, 2018 5:27 pm
Some guys run a short 6" of AC to a blank face AFCI, then feed the circuit from there. It's a bit more labor, but saves a few bucks on the AFCI breaker.
Ha! That is ridiculous.

Now I'm thinking you could just have a 9-gang box chase-nippled to the panel, with 9 gangs of faceless AFCIs.
It's usually done on older panels, where AFCI breakers aren't allowed or are way too expensive.
Usually they put 2 per 4square box.

If you needed 9 and had the space, then a new subpanel may be a better option :mrgreen:
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by Aaron » Sat Dec 08, 2018 2:51 pm

I think that EMT/MC/AC provision for AFCI exists here in the US too.

No I'm just saying that the AFCI devices are probably a lot cheaper than the AFCI breakers. So if you could just buy cheap $5 standard breakers and run nine standard circuits into raceway to a 9-gang box (that's the most gangs I've seen in a box) to nine AFCI devices, then you could run your circuits from that 9-gang box to wherever AFCI circuits are required.

I mean it's a cheapskate way to go, but it's legal and safe.

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by emtnut » Sun Dec 09, 2018 6:54 pm

Aaron wrote:
Sat Dec 08, 2018 2:51 pm
I think that EMT/MC/AC provision for AFCI exists here in the US too.

No I'm just saying that the AFCI devices are probably a lot cheaper than the AFCI breakers. So if you could just buy cheap $5 standard breakers and run nine standard circuits into raceway to a 9-gang box (that's the most gangs I've seen in a box) to nine AFCI devices, then you could run your circuits from that 9-gang box to wherever AFCI circuits are required.

I mean it's a cheapskate way to go, but it's legal and safe.
Depending on the panel, the blank faces are a LOT cheaper. I'd do it in my own place ... well, if I thought AFCIs actually did anything :mrgreen:
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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by Aaron » Mon Dec 10, 2018 2:12 am

Ha ha ha, yeah! Ugh, they are such an annoying requirement.

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by jeb101 » Mon Dec 10, 2018 8:39 am

So unfortunately, budget didn't allow me to do complete AFCI in the basement, 100$ vs 600+$ for the breakers absolutely kills the budget unfortunately, but the panel is going to be configured where all basement breakers are going to be on their own breaker, and upstairs is going to go on tandem. Bedroom and living room where ppl may crash are both AFCI, but the other 5 circuits, 4 are required for AFCI are going to be upgraded around spring time, when the inspection is due (I have 6 months to do renos). It's a temp solution until I can do it all to the new code...

I will also make room below the panel in case I need to add blank face AFCI upstairs / new circuits as I will run out of panel space, from what I can see, blank face AFCI satisfies the same code, 30$ cheaper than the breaker, but at least allows you to save on panel space.

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Re: Capacity vs Quantity. 15a vs 20a circuits

Post by emtnut » Mon Dec 10, 2018 9:13 pm

Sounds like a plan.
The blank face often works out to be a good option !
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