voltage drop

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voltage drop can occur anywhere -- new or old..... we had a new custom home with a voltage drop problem caused by the power company-service underground feeder was undersized and actually caused a fire......
 
Short answer, Yes.

Short answer, Yes.

Just tonight, went and looked at a breaker box upgrade. One of the bedrooms showed an 11.3% drop for a 20A load. My mother's house has a circuit with almost 11% at the end in the upstairs bathroom. I have seen quite a many over 5%.
 
Rewire said:
Has anyone encountered a voltage drop issue when wiring a new house
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We have had service calls to new homes, and found voltage drop, the electrician that wired the lighting the home had 14g going to both outlets, and fixtures, the owner said she ran the vaccum cleaner all the lights dimmed.
 
What type of volatge drop are you refering to? Load issues or distance? I have dealt with voltage drop because of wire size and load issues and have had to plan panel/sub-panel location in larger homes for branch circuit and HR distances. We started a 3-story 9000 sqft home this week and I am figuring panel location and wire size to minimize VD potential.
 
satcom said:
the owner said she ran the vaccum cleaner all the lights dimmed.
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That doesn't necessarily mean voltage drop. It could just mean that the circuit wasn't layed out properly to begin with and put too many lights on the circuit with the receptacles, not figuring in a larger load like a vacuum.
 
GilbeSpark said:
That doesn't necessarily mean voltage drop. It could just mean that the circuit wasn't layed out properly to begin with and put too many lights on the circuit with the receptacles, not figuring in a larger load like a vacuum.
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Poor design, and poor layout usually results in voltage drop, most of the production homes we see today, are designed for install cost not efficent design.

When you run a vaccum on a 15A general lighting circuit, in most of the production homes, you can bet your going to get voltage drop.

Expect to see more homes with reduced wire sizes, as copper prices sore.

"too many lights on the circuit with the receptacles,"
The reason we don't make a practice of putting lighting circuits on general receptacles, again cost is a big reason many combine the circuits.
 
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an area of concern with lights dimming is the invention of the "scroll" compressor in a/c units. the design if the scroll places an induction motor starting under a full load. oversizing the a/c feed helps but doesn't completely eliminate the problem because it effects voltage drop on the service itself due to the high inrush current....
 
Rewire said:
Has anyone encountered a voltage drop issue when wiring a new house
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Yes you can have a voltage drop issue. It depends on your load and the length and size of the conductors you used. Maybe some electrical practitioner do not include VD in their computation. It is also an important aspect to compute for VD just like the short circuit calculation.
 
If I do lighting in 14g, I ususally never do so in conjuction with general P receptacles for the ol' vaccuum/dim lights routine. I always design circuits and place panels to avoid the possibility of VD that interferes with satisfactory operation. However, there are times when it is more practical to run #12 and put on a 15A breaker if the meter/loadcenter is coupled together and you have HR's that have to travel a ways...
 
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