SureTest

[MMustola]

A couple of weeks ago I bought a SureTest analyzer from an inspector who was going out of business. I have never used one before. For the last couple of weeks I have been using it at all my inspections trying to figure out how to use it.

Here's the question. I have been finding a lot of outlets with excessive voltage drop. In a house today many outlets had a 12 to 15 percent drop under a 15 amp load and 17 to 19 percent drop under a 20 amp load. This seems extreme. I often find 6 to 7 percent drops

The instructions I down loaded for the SureTest indicates that the maximum voltage drop recommend by the NEC is 5 percent. I understand that the drop can be the result of many different wiring problems like: poor splices, too many splices, too many outlets on the circuit, etc.

How do some of you report voltage drop and what do you recommend?

[Eric B]

Mark:

I rarely use the SureTest. I seem to stay with just a few tried and true items for regular use - though it's worth having some of the extra stuff. Anyway, a reliable source for electric info has told me that we can fudge on the voltage drop up to about 10 percent - that 5 is a bit low for the real world.

On the few times that I do find a high drop I write it for what it is - a voltage drop of ----% was found at ---, have electrician .......

Now, do I expect that the electrician will know what I'm talking about? Not really - it's one reason I don't measure for VD.

[Bain]

I have something called the Inspector II that measures voltage drop, but I hardly use the thing anymore. Several years ago, when I used it on every job, I always felt really clever when I busted a house's outlets for excessive voltage drop.

Problem was, the electricians who came in behind me didn't have devices to confirm or deny the problem, and/or didn't know what portion of the system to check out, and/or told the seller that I was a buffoon.

I had about ten separate and meaningless conversations with ten separate and clueless electricians before I decided I no longer checked outlets for voltage drop. Don't pile on. I realize I chose the path most favored by wimps.

As a slight aside, I caught heat a few weeks ago from a woman who bought an 80 year old house that I checked out for her. She was feeling a little raw because every time she turned on the dining room chandelier and plugged her vacuum into the lone dining-room outlet, the breaker tripped, apparently because the chandelier and outlet were wired into the same circuit.

In my experience, instead of using a SureTest or an Inspector II, it may be more prudent to lug around a vacuum cleaner to test the outlets.

[Jeff Remas]

Stop checking voltage drop. Easy answer. It is beyond your expertise and standard of practice.

I am aware of an inspector who would exceed the standards to a point where an arbitrator found him reporting at the expert level. He missed something that was beyond the scope of his normal home inspector practice but because his reports for framing were in such detail like an expert they held him accountable for a $35,000. claim.

You can exceed the SOP, we all do but unless you are an expert, don't start reporting things your little gadget tells you if you really are not an expert in that area.

Hint #1 you bought if from an inspector going out of business.

[Jim Katen]

Originally posted by MMustola

A couple of weeks ago I bought a SureTest analyzer from an inspector who was going out of business. I have never used one before. For the last couple of weeks I have been using it at all my inspections trying to figure out how to use it.

Here's the question. I have been finding a lot of outlets with excessive voltage drop. In a house today many outlets had a 12 to 15 percent drop under a 15 amp load and 17 to 19 percent drop under a 20 amp load. This seems extreme. I often find 6 to 7 percent drops

You're going to find voltage drop above 10% somewhere on pretty much every house you inspect. You can bet that the electrician who follows you will not have a Suretest. He'll have a multimeter. He'll stick it in the receptacle, read 120v and announce to everyone that the home inspector didn't know what he was talking about. (Just so you know.)

The instructions I down loaded for the SureTest indicates that the maximum voltage drop recommend by the NEC is 5 percent.

That's simply not true, though it's a great way to sell Suretests. The NEC has what's called a Fine Print Note (FPN) in section 210.19(A) that recommends branch circuit conductors be sized to prevent a voltage drop in excess of 3%, or a total drop of 5%, including feeder losses, to provide "reasonable efficiency of operation." FPNs are *not* enforceable.

The NEC does recommend in 110.3(B) that listed equipment be installed according to its instructions. Lots of equipment out there includes instructions that require voltage to be within 10% of the label voltage. That's kind of a round about way to the NEC though.

I understand that the drop can be the result of many different wiring problems like: poor splices, too many splices, too many outlets on the circuit, etc.

Poor splices, backstab connections and small-gauge wire, yes.

Too many outlets and too many splices, no.

Most of the voltage drop that you'll find will be because the circuit is long and the wire is thin. This is a harmless, but wasteful condition. If the voltage drop is very great, it might damage sensitive equipment, particularly motors.

Some of the voltage drop will be the result of a series of high-resistance connections, such as the backstab connections on receptacles. These can occasionally be a hazard, but most often, they're just like the thin-wire condition above -- wasteful but not particularly harmful.

Occasionally, you'll find a lot of voltage drop from one receptacle to the next. This is usually caused by a bad connection and, if the circuit is burdened with a large load, the bad connection could overheat and cause a fire.

The problem with a Suretest that's used in the context of a home inspection is that you're likely to end up flagging lots & lots of harmless conditions while the chance of actually catching a real problem is slim.

How do some of you report voltage drop and what do you recommend?

I gave up on testing for voltage drop years ago. It's too much of a hassle, it *always* results in arguments with electricians later, and it distracts me from looking for real problems.

To do it properly, you've got to figure out how the circuits run and test them in sequence so that you can monitor the drop as it increases. You need to look out for sudden large differences in drop, not steady incremental ones.

When I used to test for voltage drop, I included the attached explanation. It helped, but not enough.

- Jim Katen, Oregon

Download Attachment: VOLTAGE DROP.doc

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[hausdok]

Hi,

I've had a SureTest for about 8 years. For about the first year or so after I bought it I too used to test for voltage drop; then I learned about Jim's roundabout way of getting to the NEC and I thought about that a little bit. 10% voltage drop - if the voltage is supposed to be 120 volts delivered to the fixture but the allowable range of voltage is 108 to 132 volts, then you're allowed 120 volts + 10% anyway, no?

So, logic dictated to me that if I'm checking the circuits in a house and my suretest tells me near the panel that there's about 119 to 120 volts then I just ignore the voltage drop readout and keep my eye on the voltage reading as I move farther away from the panel and ensure that it never drops below 108 volts at any receptacles I'll be fine. Now, maybe that's an over simplification; but, being an electrical systems moron it makes sense to me so I went with it. So far, it's never bitten me.

I mean, let's be realistic, if you tell an electrician that there's excess voltage drop how is the electrician going to verify it if he doesn't have a SureTest - he'll just use his multimeter and test it at every outlet as he moves away from the panel. Won't he only be looking to ensure that it never drops below 108 volts (a 10% drop below optimum)? Yeah, yeah, I know, if there are a bunch of things plugged into the circuit and you're at the end of a circuit with excess drop you could have readings below what you need, and the SureTest wouldn't have detected those in an empty house or with everything off on the circuit, so there's no practical use for this voltage drop test in the context of a home inspection as far as I can see. Anyway, Yung knows to come straight to me if voltage reading ever drop below 116 volts or exceed 124 volts; otherwise, she considers them normal and doesn't write them up. So far, it's worked great for most of the last 6 years.

ONE TEAM - ONE FIGHT!!!

Mike

[SonOfSwamp]

Writing up voltage drop because a SureTest says there's too much voltage drop is a perfect way to start an endless argument.

When I used a SureTest, I snuck and did it when nobody was looking. I never wrote up voltage drop.

WJ

[MMustola]

It's always fun when you get a new tool. The SureTest was providing me with a lot of information that I never had before and a found it very interesting. I have no burning desire to do a technical exhaustive electrical inspection, I'm just trying to figure out if any of this new information would be helpful to me and if it's worth reporting.

For the record, I searched the archives for SureTest. There was a lot of information but most if it was from 2005 and 2006. I wanted to see if peoples view on voltage drop reporting had changed.

[Chris Bernhardt]

Years ago I had a complaint that I missed a weak breaker in the electrical panel. When ever the client plugged their vacuum into one of the living room receptacles it would throw the breaker.

After that I put together my own test equipment using a hand held hair dryer, ammeter and voltmeter to load test circuits and measure voltage drop.

I used the equipment for a few weeks and then gave up on it. Every house I checked had voltage drops in the 10% area at the end of the longest circuit as has been pointed out already.

Later I got a Suretest, used it a couple of times, shrugged my shoulders and went back to just using a three light tester.

Every once in a while I will break out the Suretest to confirm something. In my opinion the Suretest, at least the one I have is a piss poor design of an electrical tester. The thing is unreliable, and reports conditions like ungrounded receptacles that are indeed grounded.

Chris, Oregon

[Jeff Remas]

In my opinion the Suretest, at least the one I have is a piss poor design of an electrical tester. The thing is unreliable, and reports conditions like ungrounded receptacles that are indeed grounded.

Yes, yes and yes.

The suretest uses a calculation when it places a small load on a receptacle. According to the literature it is very accurate but in my opinion, not placing a full load is not very accurate.

My suretest sits in my bag and looks pretty.

[Chad Fabry]

I use the SureTest and it's not yet given me any reason to doubt the results it provides.

When I instruct, I'm provided with a receptacle board of errors wired by Douglas Hansen and the SureTest identifies all problems except for the particularly deviant reverse polarity with a false ground. That dangerous and nefarious combination is extremely unlikely to ever be achieved in real life.

Only a truly warped mind would do it.

[Bain]

Originally posted by Chad Fabry

That dangerous and nefarious combination is extremely unlikely to ever be achieved in real life.

Only a truly warped mind would do it.

Who ratted me out?

[hausdok]

Yeah,

I still use it too; I don't look for excess voltage drop but it finds the excess voltage, too low voltage, bootleg grounds, open grounds, excessive ground impedance, reversed polarity, no neutrals or hot/grounds reversed just fine.

I think it's biggest deficit is that it can't spot two errors at the same time as Chad has stated. Other than that, it's earned its keep.

I'll never trust a 3-light tester anymore; not after a licensed electrician didn't believe my SureTest when I'd identified more than a dozen open grounds and the electrician used a 3-light tester to confirm that the SureTest was wrong. I handed him a screwdriver and told him to open up a receptacle, and then another, and then another; all of them had the EGC snipped away! That 3-light tester said all was fine though.

If I didn't have the SureTest, I'd use a Wiggy or a multimeter before I'd use a 3-light tester.

ONE TEAM - ONE FIGHT!!!

Mike

[Chris Bernhardt]

I'll never trust a 3-light tester anymore; not after a licensed electrician didn't believe my SureTest when I'd identified more than a dozen open grounds and the electrician used a 3-light tester to confirm that the SureTest was wrong. I handed him a screwdriver and told him to open up a receptacle, and then another, and then another; all of them had the EGC snipped away! That 3-light tester said all was fine though.

Interesting. I came to my conclusion because I did pull covers and recepatcles when I started getting conflicting indications between the three light test and the Suretest that I own and found the Suretest to be the one that was wrong.

Usually if there's some leakage that's causing the three light tester to appear to be indicating correctly I can tell but it doesn't take but a few volts to get those indicators fully on and indistinguishable.

I would do what Jim K. does. Uhh, How does Jim K. test the receptacles?

Chris, Oregon

[Eric B]

I think that the meter can be useful when you're looking for a little additional info to something else already found.

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[randynavarro]

Every time I read a thread about using a SureTest, there are equally valid arguments for and against. Every time.

The confusion remains. . .