Double tapped breaker question

Location
New York
Occupation
Electrical apprentice
Does anyone see an issue with taking two circuits off separate breakers and splicing them together with a single tail off to one breaker to make space for adding a ckt to that panel?

Or is adding a tandem the better option? I’ve seen both plenty of times.

Of course as long as each ckt you combine is a small load and each ckt has their own neutral. A multiwire splice would overload the neutral on one phase but the other method you’d have a separate neutral return for both hots
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
So you have an existing "double tap" and you want to correct it by combining the two conductors in a splice a pigtail a single conductor to the CB? That would correct the double tap condition but there could be other issues with what that circuit is actually for.
 

retirede

Senior Member
Location
Illinois
Technically, what you’re describing is not a double-tap, which is defined as landing two wires on a single breaker (no prior splice to a single conductor).

Like Infinity says, you need to make sure combining those circuits is allowed. Example, if one is a SABC or bathroom receptacle, it likely can’t be combined with another circuit.
 

ammklq143

Senior Member
Does anyone see an issue with taking two circuits off separate breakers and splicing them together with a single tail off to one breaker to make space for adding a ckt to that panel?

Or is adding a tandem the better option? I’ve seen both plenty of times.

Of course as long as each ckt you combine is a small load and each ckt has their own neutral. A multiwire splice would overload the neutral on one phase but the other method you’d have a separate neutral return for both hots
Either way is fine unless your combined load would trip a single breaker if they were tied together. In that case, you would use a tandem and keep the hots and neutrals separate. If you tie the hots together with a pigtail, you could do the same with the neutrals, as they would carry the same current as the hot conductors. If they are side by side in the panel, I would verify what they serve, to be sure they aren't feeding a 240 volt load and someone forgot to use a handle tie and also as retirede said, make sure they aren't bathroom, laundry, kitchen, etc. that can only serve those loads.
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
If it's just about space, and the panel accepts tandems, then the tandem is the better option since you're not doing anything that changes the overcurrent protection in a way that would cause a breaker to trip.
 

mtnelect

HVAC Contractor
Location
Southern California
Occupation
Contractor
Either way is fine unless your combined load would trip a single breaker if they were tied together. In that case, you would use a tandem and keep the hots and neutrals separate. If you tie the hots together with a pigtail, you could do the same with the neutrals, as they would carry the same current as the hot conductors. If they are side by side in the panel, I would verify what they serve, to be sure they aren't feeding a 240 volt load and someone forgot to use a handle tie and also as retirede said, make sure they aren't bathroom, laundry, kitchen, etc. that can only serve those loads.
That is why I am proposing a change to the NEC 2026. See attached.
 

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jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
That is why I am proposing a change to the NEC 2026. See attached.
That is already covered by 200.4(B). It's one of the more important code sections that I see routinely ignored and not enforced. But if it's already in the code and people ignore it, adding more language probably won't change that. :rolleyes:
 

kwired

Electron manager
Location
NE Nebraska
That is already covered by 200.4(B). It's one of the more important code sections that I see routinely ignored and not enforced. But if it's already in the code and people ignore it, adding more language probably won't change that. :rolleyes:
Agree it already covered in section you mentioned. And entering the box via a separate cable is a way of grouping it with it's associated ungrounded conductor(s) so no additional identification method is needed in that situation.
 

acrwc10

Master Code Professional
Location
CA
Occupation
Building inspector
I’m going with zombieland when it comes to “double tap”
 

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Location
New York
Occupation
Electrical apprentice
Either way is fine unless your combined load would trip a single breaker if they were tied together. In that case, you would use a tandem and keep the hots and neutrals separate. If you tie the hots together with a pigtail, you could do the same with the neutrals, as they would carry the same current as the hot conductors. If they are side by side in the panel, I would verify what they serve, to be sure they aren't feeding a 240 volt load and someone forgot to use a handle tie and also as retirede said, make sure they aren't bathroom, laundry, kitchen, etc. that can only serve those loads.
@ammklq143 what would the point be to tie the neutrals together? Im assuming you mean in the panel so that only one neutral of the two goes on the neutral bar? Maybe to free up a slot or for the rsn that the neutrals are really one since you doubled two ckts under one ?
 

tom baker

First Chief Moderator
Staff member
Home inspectors frequently cite “double tap”. Some breakers are listed for two wires under one lug, to determine if that’s allowed requires removing the breaker to see what the labeling on it states
 

kwired

Electron manager
Location
NE Nebraska
Home inspectors frequently cite “double tap”. Some breakers are listed for two wires under one lug, to determine if that’s allowed requires removing the breaker to see what the labeling on it states
Or having previous knowledge of what it does permit ;)

30 amp and less QO and Homeline breakers have always been listed for one or two conductors. Others I would generally need to look at though simply because I don't deal with them as often.
 
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