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Adding a new 15A circuit to this panel

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1HandyWoman

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Hi everyone,

I need to add a new 15A circuit breaker to this breaker box and there seems to be two spots left in the panel. See pic. The question I have is...

even though there seems to be two spots left (punch outs there were already punched out) at the bottom of this panel, the bar behind the punch outs is running horizontally and not vertically.

From my recollection of many years ago when I added a new circuit breaker to a panel, the breakers latched onto that bar to make the contact with the incoming power. Maybe my recollection is erroneous (hey it was many years ago and my memory aint what it used to be).

So bottom line, do you think I can add a new circuit breaker to this panel?
 

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afjes_2016

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It is difficult to make out in any detail from the picture you have provided. Is it possible to take a clear picture.

My eyes are not so good at my age of 64 so maybe someone with better eyes can help you more but from what I can tell that seems to be a Seimens panel (going by the breakers only).

What is your skill level? If need be are you comfortable with removing the front cover of the panel? Is there a label somewhere on the front cover giving the model/brand of the panel?
 

1HandyWoman

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Sorry about the picture quality it was taken with an old digital camera (dont have a smart phone, will never have a smart phone).

I am fairly handy and COULD take the cover off but I installed a huge shelving unit that covers the screws on the left hand side so taking off the cover is going to take some time and effort (yes I know I will have to take it off to add the circuit).

I looked on the panel and I cannot take a picture... I focus and when I hit the button to take a pic, it unfocuses out of focus... damn. I will read the instructions on the damn camera again and see if I can get a nonfuzzy pic. But yes it is a seimens box, type I.
 

Snoonyb

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There won't be a horizontal buss bar, so when you remove the shelving and remove the cover you should find the neutrals connected there. You also have an example, on the right of the panel, of the type of breaker that can be substituted in place of the full sized breaker/s on the left, the choice is there for you.
 

1HandyWoman

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OK I finally got a decent pic of the information on the box (top pic).

I also looked closer at the bar running horizontally across the two punchouts and I think I found my answer.... NO.

It does not look like a breaker could go into either of these punchouts because that bar looks like it is in the way of a breaker seating (hard to see but second pic). The horizontal bar looks like a jumper of something to connect the two side vertical bars that the breakers latch onto.
 

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1HandyWoman

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There won't be a horizontal buss bar, so when you remove the shelving and remove the cover you should find the neutrals connected there. You also have an example, on the right of the panel, of the type of breaker that can be substituted in place of the full sized breaker/s on the left, the choice is there for you.
But the full sized breakers on the left are 20A circuits and the half sized breakers on the right are 15A breakers. Also on the right although they look like half size are "fused" together so two 15A breakers are fused to make the same size as the one 20A one. So I dont think that is an option on this type of box but that is why I am asking the experts here.
 

Snoonyb

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Buss bars are not connected by a jumper.

Common residential is 240V single phase, IE. two 120V- 180 degrees out of phase.

Those breakers are made that way and each is a switch that supplies 120V, 15A to a conductor, so there are two separate supplies from the same breaker, from the same buss bar.

I could go into the weeds with this, which would probably be even more confusing.

Simply put, you could just add either a single breaker, as those on the left, or replace one with the same style that is on the right, which would be feed from that buss bar.
 
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1HandyWoman

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Buss bars are not connected by a jumper.
Ok well I do not know the lingo of breaker boxes so my bad.

What it is or what it does I do not know but it is a bar that is connected to both sides of the box that has "buss bars" or whatever those bars are that run vertically and which the breakers are latched onto.

So the horizontally running bar is in the way of putting another breaker in the punch out IT SEEMS to me.

So is there anything else I can do to install a new 15A circuit? Anything? or am I fked?
 

1HandyWoman

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OK I finally got the cover off the box. Here is what it looks like inside. Again not the clearest pic but the best I could do with the camera I have.

I can now see that the bar running horizontally at the bottom (blocking the two punch outs) is definetely a jumper tying the neutrals together as the pic shows the neutral coming in the house is only connected at the top right, so the "jumper" is needed.

Ok so now I think it is certain I cannot add a new circuit breaker in this box. Is there any alternative to doing that without piggybacking the new circuit into another existing circuit?
 

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1HandyWoman

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Buss bars are not connected by a jumper.

...

Those breakers are made that way and each is a switch that supplies 120V, 15A to a conductor, so there are two separate supplies from the same breaker, from the same buss bar.

I could go into the weeds with this, which would probably be even more confusing.

Simply put, you could just add either a single breaker, as those on the left, or replace one with the same style that is on the right, which would be feed from that buss bar.
OK I THINK I follow what you are saying.

So then my followup question would be (if I am at all understanding what you said) ....

can I replace one of the 20A breakers on the left side with a smaller (half sized) 20A breaker (to supply the existing 20A circuit) and a new half sized 15A breaker for the new 15A circuit????
 

geochurchi

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Correct, remove 1 full size breaker from the left and install 15/20 breaker. number for it should be on the panel cover.
Geo
 

WyrTwister

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Is there a reason you wish to install a 15 amp circuit , in stead of a 20 amp circuit .

Were it me , I would run a 12/2 W/ground Romex for the circuit , remove one of the 20 amp circuit breakers and install a 20/20 twin circuit breaker in its place . Terminate the origional wire to one of the terminals on the new circuit breaker . Terminate the black wire of the new Romex on the other terminal of the new twin circuit breaker . Terminate the new white wire to the neutral bar and the new bare ground to the ground bar .

God bless
Wyr
 

Jeff Handy

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In some boxes, the mini breakers are only allowed in certain positions.

The info panel on the door might indicate where they are allowed.

And yes, why not run 20 amp breakers and 12 ga wire?
Very small cost increase and much more future proofed.
More juice is more better.

Just remember, when you turn off the main breaker, there is still deadly power in the box.
The exposed ends and connections of the two line wires are always hot.
And there can be a small nick anywhere in their insulation that can kill you if you touch exposed wire.

Wear gym shoes, and put a piece of carpet or wood under you, use insulated tools, don’t handle any wires by hand.
Never touch the box while wiring with the other hand.

Get a better camera, they are so cheap now, even on eBay, Nextdoor local app, etc.
Good old ones for $20.00.
 

Jeff Handy

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You can also get an old used smartphone with a decent camera for $20.00 or so.
You can offload the pics with a usb cable, or in some a mini SD card can pop out and plug into your computer, sometimes you need a card adapter to hold the mini card.

Just to use it for the camera, and no need for cell service.

Wrap it in foil if you are paranoid.
You can get Faraday cage phone covers also, to block all wavelengths.

You can still dial 911 even with no paid phone plan, very handy in emergency or to carry in your car.
 

tomtheelder2020

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If most slots already filled, is there a concern about the new breaker exceeding the total amp capacity of the box? Thinking about this, I looked at my own box and found it is rated for 200 amps, has 20 slots for breakers, and has 9 breakers totaling 310 amps (including 2@50 amps and 2@40 amps). It has had that configuration for something like 20 years. Should I be on the phone with an electrician?
 

Jeff Handy

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If is very unlikely that 2/3 of your breakers will be loaded at max capacity all at once.

My former house got by on 100 amps with eight people living there, including a/c and four girls with hair dryers.
With electric range, and double wall oven.
Yes, the lights dimmed a little when the a/c was starting up.

One of your big dual breakers is likely your a/c, the other is pbly your oven, stove, range, or clothes dryer.

If you have natural gas, you can switch a big draw appliance to that, to remove some load from the breaker box.
 

Johnboy555

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If most slots already filled, is there a concern about the new breaker exceeding the total amp capacity of the box? Thinking about this, I looked at my own box and found it is rated for 200 amps, has 20 slots for breakers, and has 9 breakers totaling 310 amps (including 2@50 amps and 2@40 amps). It has had that configuration for something like 20 years. Should I be on the phone with an electrician?
After seeing the picture of the box I seem to remember (from 100 years ago) that there was something in the building codes about "total amps of breakers" allowed in the box. If I remember correctly, that problem could be addressed by adding a "side box". You need to speak with a full licensed electrician, or city building inspector.
 

Jeff Handy

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Adding a sub panel to avoid over-filling the main box would not reduce the load on the home electrical system’s capacity.

But it might avoid a code violation for too many breakers in a box, or for using mini breakers if not allowed, or too many of them or in the wrong slots.
 

tomtheelder2020

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Johnboy and Jeff, the two 50 amp breakers feed the 100-amp fuse box that was original to the 1951 house and is now a sub-panel. The two 40-amp breakers feed the AC - and the reason the new panel was installed 30 years ago.
Jeff, thanks for pointing out that what matters is actual load, not possible load (though City inspector might think differently). My 100-amp fuse panel will never again come close to capacity as the garage and major kitchen appliances are now on new circuits I installed, and house lights are all now compact fluorescent and LED, Thanks for putting my mind at ease.
1HandyWoman, however, might not be so lucky and should check what her actual loads might be before adding a new circuit.
 

WyrTwister

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If you are worried about the total connected load , use a clamp on amp meter and leasure the load , on both phases / hots , coming into the panel . If you are qualified to do that , safely .

God bless
Wyr
 
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