Panelboard Usage

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As an independent building inspector/consultant, I must admit that many of the code violations and amateur wiring I've come across over the years never ceases to amaze me. In fact what amazes me the most is what people actually get away with without suffering the consequences. The most recent case involves what appears to be a home owner installed 30A 120/240V single-phase subpanel. Only thing is, the person who installed it decided to use it as a 120V subpanel by jumpering the line side lugs. The panel is essentially supplied by 2-#10 AWG copper conductors in conduit, i.e., one ungrounded and one grounded conductor. I have to admit that the person/s were at least smart enough not to use multi-wire branch circuits since each branch circuit consists of one ungrounded and one grounded conductor. Regardless, my contention is that this still remains an unorthodox, improper and potentially unsafe installation since another amateur done the road could easily add multi-wire branch circuits without realizing that this is an accident looking for a place to happen. I should also add that the person/s who installed this panel bonded the neutral busbar to the enclosure (not allowed) not to mention that there are a total of (6) 15A 120V circuits being supplied by this 30A 120V subpanel.
All said, am I wrong in flagging this installation? I've also added a photo for further clarification. All comments and feedback regarding this matter are appreciated.
 
As an independent building inspector/consultant, I must admit that many of the code violations and amateur wiring I've come across over the years never ceases to amaze me. In fact what amazes me the most is what people actually get away with without suffering the consequences. The most recent case involves what appears to be a home owner installed 30A 120/240V single-phase subpanel. Only thing is, the person who installed it decided to use it as a 120V subpanel by jumpering the line side lugs. The panel is essentially supplied by 2-#10 AWG copper conductors in conduit, i.e., one ungrounded and one grounded conductor. I have to admit that the person/s were at least smart enough not to use multi-wire branch circuits since each branch circuit consists of one ungrounded and one grounded conductor. Regardless, my contention is that this still remains an unorthodox, improper and potentially unsafe installation since another amateur done the road could easily add multi-wire branch circuits without realizing that this is an accident looking for a place to happen. I should also add that the person/s who installed this panel bonded the neutral busbar to the enclosure (not allowed) not to mention that there are a total of (6) 15A 120V circuits being supplied by this 30A 120V subpanel. All said, am I wrong in flagging this installation? I've also added a photo for further clarification. All comments and feedback regarding this matter are appreciated. For some odd reason, the image in my original post didn't take, so I have added it to this reply. Sorry, but this appeared to be the only way to do this.
DSCF3064.jpg
 

Sierrasparky

Senior Member
Location
USA
Occupation
Electrician ,contractor
I don't belive this is entirely a code violation.
A load calc would determine if the panel is overloaded. As far as using the panel a 120v only I don't see this as a issue as you claim. There could be another reason for a violation. other than the bond and the white tape on the black
 

Jim W in Tampa

Senior Member
Location
Tampa Florida
120 Part is legal
6 breakers may be fine
white tape is violation
the jumper if cut is illegal
bond strap needs removed
Your partly correct so yes tag
Dont really see the white tape as a biggy but that bond needs removed
3rd breaker on left is not being used. It can stay
What is the orange glow on right from ? Camera or is it overheated ?
 

Chamuit

Grumpy Old Man
Location
Texas
Occupation
Electrician
Is the feeder lug rated for more than one conductor?

I'd agree that the "feeder" wire is bigger than #10.

If it's a subpanel as you say, the neutrals and ground have to be seperated.
 
Panelboard Usage

In answer to replies:

The orange glow in the photo is due to the camera lighting. No signs or indications of overheating were present. I stand corrected, the supply conductors are #8 AWG THHN,THWN Copper.

That said, I don't see how the 30A supply is adequate for (6) 15A 120V circuits. Also, as mentioned in my initial post, what if someone later decides to fill the panel let alone install multiwire circuits, i.e., two ungrounded conductors paired with one grounded neutral. Can't happen since both bus bars are supplied by one and the same wire. This in turn could overload and burn up the neutral conductor. Also, what about original equipment design? I really don't think that this is what the equipment manufacturer had in mind when they designed and manufactured this panel. Once again, doesn't equipment design and intended usage have any bearing whatsoever on the installation, especially with regard to safety? If we just go by the code and remove the bonding strap from the neutral bus, am I to believe that all is well and forget about what may happen done the road? In all due respect, based upon what I have seen over the years, this is a hard pill to swallow.
 
Panelboard Usage

In answer to 'Is the feeder lug rated for more than one conductor?'

Don't really know. This was also an older ITE panel (with a 125A 120/240V rating) serving a dwelling built back in 1948. Nothing anywhere to indicate that the lug was designed, rated and approved for more than one conductor. So I would have to say, No. As we all know the labels on older equipment are a far cry from what they are today.

While we're at it, I should also add that the main service panel was also an older ITE panel, supplied by #3 AWG copper SE conductors with a 100A 2-pole breaker. Interestingly enough, they soon ran out of space given room for only (20) single pole devices. So someone then decided to install single pole tandem breakers to accommodate additional circuits. Only thing is, I read labels no matter how old and for this particular panel, the bus diagram on the label does not indicate single pole tandem devices. What's really interesting about this whole situation is that the dwelling is less than 1,200 S.F. and one doesn't have to do a load calc to know that the 100A service is adequate as there is only 1-240V circuit for the AC unit. It's seems obvious that whoever did this would have been better off updating the main service panel to begin with.
 

pete m.

Senior Member
Location
Ohio
That said, I don't see how the 30A supply is adequate for (6) 15A 120V circuits.

It may not "look" right having a 30 amp feeder for 6 - 15 amp branch circuits, but apply the same thinking to the 100 amp service panel that is filled with 15, 20 and 30 amp breakers.

A load calculation needs to be performed on the sub-panel (once the other defects are corrected) to determine whether or not it is in fact overloaded.

Pete
 
One does not add the circuit breaker value up to find the load of the panel.
One or more of the circuits may be supplying receptacle circuits with no loads plugged in. That would be the reason for a load calculation

If this is a subpanel, there is no restriction as to the number of circuit breakers without a main breaker.
 
I would question if the main lugs are listed for use with more than a single conductor. The panel also appears to be recessed more than 1/4" in the wall.
 
Panelboard usage

Panelboard usage

> One does not add the circuit breaker value up to find the load of the panel.
> One or more of the circuits may be supplying receptacle circuits with no loads >plugged in. That would be the reason for a load calculation

The above is agreed and clearly understood. However, I was going by the six or more circuits rule which I gather does not apply to the sub-panel. I'm still surprised that no one has bothered to comment about this installation with regard to the possibility of adding more circuits let alone multi-wire circuits and the ramifications thereof.
 
> If this is a subpanel, there is no restriction as to the number of circuit breakers without a main breaker.

In this particular instance, I agree but such may not always be the case in referring to NEC section 384-16(a) pertaining to Overcurrent Protection of panelboards.
 

acrwc10

Master Code Professional
Location
CA
Occupation
Building inspector
> If this is a subpanel, there is no restriction as to the number of circuit breakers without a main breaker.

In this particular instance, I agree but such may not always be the case in referring to NEC section 384-16(a) pertaining to Overcurrent Protection of panelboards.

What does 384-16(a) have to do with this installation? You may want to check your code numbers again.:)
 
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