Right but how does the Suretest read the resistance for instance. In my mind, I am thinking that if it has two of the variables it can figure for the other. But the menus give impedance for hot, neutral, and ground. I suppose you had get RMS voltage for all three. But then you need current.
Besides all that though. I am beginning to believe that most of the homes in Dallas have high voltage drops, and I to have seen voltage drops in the teens and no explination as far as distance from the panel. I am getting the hang of troubleshooting with it. I am paying attention to the circuit and the reading going along in series to differentiate where an issue may be between the receptacle and panel, or maybe a bad receptacle, or bad install (stablock). I found it interesting that in a kitchen where the client complained about a GFCI nusience tripping, that the 20A test would trip the Outlet and the voltage drop however was not off the chart. In that case I believe the GFCI was masking a reverse polarity issue. It went into the report recommending a licensed electrician look into it.
I think it is a valid service to offer if you choose to offer it. Is it outside the scope? Not going to go there. I understand the builders are very cavalier about voltage drops, in their minds it is right if its a 14 gauge wire for a 15A circuit or 12 for 20A. They will smirk, and show the client voltage reading at the panel and then one at the outlet and call it good. Of course without a load its all irrelevant, but the client does not know the difference. Bottom line though is that I have found some big drops between 14 and 19 more than once and that is a dangerous drop.
But HI’s really have a hard time doing what they don’t understand (even when it is important to do), but on the other hand rant about stuff that isn’t needed or done correctly…
I was not trying to set a precedent as to who, what, when or where. Rather when it should be considered (if at all). If you don’t how/why to do it, you should not be doing it.
So you are not sure what other circuits are mandatory for 20A?
Somewhere along the line, in my studies to pass the state as well as the national professional inspector exam, it got stuck in my head that certain locations should be on 20A. For example: Outside outlets, bathrooms, garages, and of course kitchens. It has always been a point of confusion for me because you never really see the 20A outlets with the “T” post. Maybe it was just a suggestion. I cannot seem to find anything except that kitchens need to have two 20A circuits. I think maybe one was to be non-GFCI for the fridge at least?
As it stands I tend to inspect the outside first and the garage is my first room, 90% of the time I get to the service panel here and make note of the 20A circuits.
I have been on there this morning. I have been dreading to say this because it just provokes all the sneers, bologna bravado pointed questions. But I have a decades old AS degree in EE that I never really used and have forgotten most of. I’m learning but I really like to know to whole big picture to understand the various components. Its starting to come into focus for me though.
On the safety front: If a circuits voltage demand exceeds the voltage provided due to a voltage drop then current is going to make up the different and the result is heat in the wires? :-k
On the efficiency front… well actually the same as above and then the power factor plays a part also right?
Would appreciate any insight although I need to get to doing some reports and get ready for inspections tomorrow. (and my never ending honey-do list) I may jump back in LATE tonight on my tablet.
The funny thing about VD is that if the load at the end is purely resistive (like a heater) then the overall current will go done proportionally to the voltage.
That makes sense. A very good and valid point when discussing the risk of conductors over heating. But say a motor for example would cause an inverse relationship voltage to current right?
Yes it would. The motor is always trying to run at synchronous speed so it will draw more current as the voltage decreases due to VD. The heater will just have a lower heat output.
Hi. Can anyone offer a proper narrative for old home with Voltage Drop in the most remote outlets above the suggested 5%, mentioning possibility for plugged upstream devices and link to respected source, stating concrete number as “excessive” drop?
Something like: “According to example.com - 6.7% voltage drop is not considered as excessive”
There’s a distinct difference between explaining how to operate something (useful for first time homebuyers, perhaps) and explaining how something operates. When someone asks you for the time they don’t want to know how to build a watch! Report defects, NOT how something operates properly.
Many do not understand the concept of current and voltage. There is no voltage drop if there is no current flow. In fact the terms ‘voltage drop’ imply voltage used during normal operation so there must be a complete circuit and hence a load that causes current flow and voltage drop.