Voltage drops reading on the suretest

[pkunk]

I get voltage drop readings on the suretest over 5% all the time but when I check the volts from the panel and at the outlet I see 120 aprx. should I ignore the voltage drop reading?[:-bigmout

[hausdok]

The acceptable range for voltage is 108 to 132 volts. They used to say that a 10% drop was unacceptable. 108 is a 12 volt drop from 120 volts or 10%, no? I guess that's where they came up with the 108 volts.

Anyway, I've mellowed over the years. I think I'd only report it if it was in excess of 10% and reading less than 108 volts. I don't think you're going to see that with new wiring but you might see it with K & T or some of the older post-WWII stuff.

ONE TEAM - ONE FIGHT!!!

Mike

[Scottpat]

That is one of the problems (not really a problem, but just too much information) with a ShureTest tester. I use to report voltage drops, but I got so tired of electricians saying that they could not really do anyting about it because it was an issue with the utility company. Then everyone would look at me for an answer.

I stopped looking voltage drops many years back.

[Jim Morrison]

You should do a search of these forums for that info, because it has been discussed at length in the past. Jim Katen had a nice treatise on the subject as I recall.

[Ben H]

I had a bathroom the other day with 12.8vd @20amp. The house had many other eletrical issues as well, no grounds on half of the plugs, doubletaps, ect.... Time to call old Sparky!

[Marc]

That is one of the problems (not really a problem, but just too much information) with a ShureTest tester. I use to report voltage drops, but I got so tired of electricians saying that they could not really do anyting about it because it was an issue with the utility company. Then everyone would look at me for an answer.

A while back, there was a thread about feeding sub-panels from other sub-panels. That's one type of wiring practice that can result in voltage drop issues because the impedances add up. But the utility? Not a chance. Need another electrician. If you still think it's the utility, check the voltage drop on an outlet that is very near, or attached to the main panelboard.

I've never bothered with checking voltage drops but my eye is always on the lookout for light bulbs that suddenly dim for a few seconds. When I see it, the focus of the inspection is adjusted a little closer towards the electrical installation.

Marc

[Garet]

I had a bathroom the other day with 12.8vd @20amp. The house had many other eletrical issues as well, no grounds on half of the plugs, doubletaps, ect.... Time to call old Sparky!

Chances are good that Sparky won't have a clue. The voltage drop provisions are an unenforceable "fine print note" in the NEC. I used to routinely measure voltage drops of 10-20% before my Suretest got stolen.

My advice is to throw away your Suretest.

[Ben H]

I had a bathroom the other day with 12.8vd @20amp. The house had many other eletrical issues as well, no grounds on half of the plugs, doubletaps, ect.... Time to call old Sparky!

Chances are good that Sparky won't have a clue. The voltage drop provisions are an unenforceable "fine print note" in the NEC. I used to routinely measure voltage drops of 10-20% before my Suretest got stolen.

My advice is to throw away your Suretest.

I was referring to the rest of the issue's not the VD. Besides, wouldn't selling it be a better route?[]

[Richard Saunders]

If you eliminate voltage drop, the suretest is basically giving you the same info as a 10$ 3 lite tester.

[Jim Morrison]

No, that's not so. Suretests just give more information than the average HI -or electrician for that matter- can accurately interpret. They're good, but like a hammerdrill, they're just not great tools for HI's.

Jimmy

[plummen]

Do any of you guys check the voltage at the main coming into the panel? that would tell you which side the voltage drop is coming from,or am I thinking like a contractor again? [:-slaphap

[Marc]

Do any of you guys check the voltage at the main coming into the panel? that would tell you which side the voltage drop is coming from,or am I thinking like a contractor again?

Relax Jim. We're both contractors.

You're right on cue about checking voltage drop near the panel to get an idea how much of the impedance at a problem VD location is due to the premises wiring and how much is due to utility line impedance.

Marc

[kurt]

This is one of those things that's not enforceable (per Garet's explanation), so is it a defect? Is there anything we can go to that says it's a real problem?

Not really.

I stopped reporting it years ago. Every house has it, at least every house I've looked at.

[hausdok]

I wouldn't toss the SureTest. It comes in really handy when you have a house with aluminum wiring for pinpointing excessively high voltage drop that can indicate a corroded copper-to-aluminum connection.

ONE TEAM - ONE FIGHT!!!

Mike

[kurt]

True, but if I find aluminum wiring, I'm already going into danger mode and will be recommending all sorts of things.

I really don't need the Suretest to tell me that. And yes, I do have a carry a Suretest. Use it every day. Just not for determining voltage drop.

[Chris Bernhardt]

Maybe it's just mine, but I don't trust the suretest. It often seems to give me bogus readings.

One of my plans this year is to spend more time looking at a homes electrical system under load with my IR camera. I wonder what correlation exists between what the suretest says vrs infrared?

My guess is the correlation is poor.

Chris, Oregon