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Voltage Drop at receptacles?

Voltage Drop at receptacles?

New postby RobShepp on Tue Nov 18, 2014 10:26 am

Good morning,
recently I have started using a Suretest 61-165 Circuit Analyzer on all interior and exterior receptacles. As you know, this device will test for voltage drop to the receptacle during testing. I have had mixed reactions to this from Electricains...but all have pretty much agreed that the problem could not be fixed and was part of "normal operation". One electrician, of whom I do trust, likended it to a car having a speedomoter that reads 180mph when the car can only go 120mph since the receptacle would most likely never have anything plugged into it that would draw what the meter is testing for. I didn't agree and use my own interpretation of VD from the NEC fpn and a written statement about the concerns relating to a decrease in voltage. This has come to a head on a recent inspection of the brand new 4 million dollar SFR in Broward County, Florida. Roughly 75% of the receptacles tested for 14%+ VD with some over 20% VD. The contractor's electricain stated that this wasn't a problem and was actually in an unenforceable location of the NEC. No repair was made from there. My question is...what, if any, language do you use or recommend to relate this issue to the client and keep from being impeached by uneducated contractors? thank you in advance.
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Re: Voltage Drop at receptacles?

New postby Jerry Peck - Codeman on Tue Nov 18, 2014 7:18 pm

The electrician is correct that voltage drop is unenforceable, however, high voltage drop readings are a result of inadequate planning and (oftentimes) cost savings and poor workmanship.

I always referred to 90.1(B)
- 90.1 Purpose
- - (B) Adequacy. The code contains provisions that are considered necessary for safety. Compliance therewith and proper maintenance results in an installation that is essentially free from hazard but not necessarily efficient, convenient, or adequate for good service or future expansion of electrical use.

"but not necessarily efficient, convenient, or adequate for good service"

And electricians and electrical contractors think that meeting the minimum requirements of the NEC is a real big deal - the NEC itself says it that meeting the NEC might not be adequate, efficient or convenient.

On any house over a entry level production house ... the NEC should never come up as penny-pinching only goes on in entry level-production houses.

Now to the actual problems:

The most likely cause is that they likely used back stabbed devices on their 15 amp circuits and back stabbing if a major cause of voltage drop.

Another likely cause (after backstabbing devices) is they likely have all the panels in one location (the garage) and now have to run 200 feet of wire to the other end of the house ... if they do not up-size the wire size they WILL have voltage drop issues.

The speedometer being off is not an applicable analogy, maybe this is - your car uses more fuel the faster you go, and saves fuel by driving slower, unless the car's computer is set wrong and then it drinks fuel like it's Kool-Aid ... and that is what voltage drop is doing - you don't have to be using the circuit at its maximum capacity to waste energy with voltage drop.

Additionally, may appliances and computers (and many appliances have computers in them) give a maximum range for the voltage, and the lower range may not be met if there is voltage drop. Let's say the circuit has 120 volts on it, a 15% voltage drop is 18 volts, which means the voltage is really only 102 volts ...

Voltage drop enforceable? Only after you get your clients to understand what voltage drop does to them and their appliances, and then THEY "enforce it" with the builder, and after the builder has to correct it a couple of time, the BUILDER "enforces it" with their electrician. I went through this with some high end builders in Palm Beach County, a few of them realized that the cost of pulling in #12 wire for 15 amps circuits was not much compared to the flack they got from their clients for having pulled in #14 and now had voltage drop.

Another solution is to go back to installing remote panels, one in the downstairs hall, another in the upstairs hall, that means the circuit length was dramatically reduced and voltage drop due to the length of the circuits was dramatically reduced.

The language I used to address voltage drop was 90.1(B), especially this part "but not necessarily efficient, convenient, or adequate for good service".

The NEC is about "safety", and "not necessarily efficient, convenient, or adequate for good service".
Jerry Peck - CodeMan
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Re: Voltage Drop at receptacles?

New postby RobShepp on Thu Nov 20, 2014 12:02 pm

Thank you Jerry.

I have been lucky enough to have Jeff Hooper as my mentor lately, and I recently meet Ron Sabac and have had a couple phone conversations with him about my reports and inspections. I can honectly say, it feels like nobody is watching what's going on out there.
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Re: Voltage Drop at receptacles?

New postby Jerry Peck - Codeman on Thu Nov 20, 2014 4:55 pm

RobShepp wrote:I have been lucky enough to have Jeff Hooper as my mentor lately, and I recently meet Ron Sabac and have had a couple phone conversations with him about my reports and inspections.


I must say that you are hanging around excellent company.

Jeff, Ron, and I used to be the three in the top end of the market in South Florida, Ron retired and moved, I retired and moved, and that left Jeff to keep the market up and going - you need to meet Tom Glynn too, he took over some of the business Ron and I had that Jeff didn't get.

I'm not sure who has the top end of the market down there now, Jeff has some, Tom has some, but most other inspectors don't venture into that market, or venture into that market but their inspections and reports don't fulfill the expectations of those clients.

Keep in touch with those three, Jeff, Ron, and Tom, as (contrary to what some think) there is room in that market, in fact, it takes those types of inspectors to get together to maintain and expand that market ... a few more top of the line inspectors leads to more clients for everyone.
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Re: Voltage Drop at receptacles?

New postby RobShepp on Thu Nov 20, 2014 5:44 pm

I meet Tom glynn at the last FABI conference, i'm using part of his genral information section in my report(with his permission). Good guy, really good reports....
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