False Ground / Bootleg Ground

In the last 5 inspections, I found bootleg grounds. I am using an Ideal Suretest. But up till the last 4 my analyzer never reported this. In some of these houses, there are a few outlets that are OK. But most are getting reported as a false ground. Some of these houses are new construction some are several years old. Anyone want to toss in their .02?

Have you actually checked the ground to verify that it has been “bootlegged?”

The SureTest measures the resistance between the grounding conductor and the grounded conductor. If there is not enough resistance (as determined by the meter) the SureTest will indicate a “false” ground. This can (and often does) occur when the receptacle is close to the panel (where the neutrals and grounds are bonded).

In newer systems, even in long runs, there is very little resistance and you may get this reading even on the other side of the house (I find it most often in GFCI receptacles). This is, in part, due to quality materials and quality installations.

The indications given by our SureTest meters has to be interpreted. It requires an understanding of the meter and the electrical system in order to make accurate interpretations.

Read through your manual and you may get a better understanding of what your meter is really telling you.

Yeah, might have some angry homeowners in your future.

So, why do you not simply think your SureTest is out of calibration, i.e. “broke” and just needs to be serviced or repaired?

Thank you Jeff.

Michael. Thats was my fear, but after reading the manual I found there was more to it than just a broken tool.

Mat- as usual, Jeff is right on the money. The sure test is much less effective in new buildings because of the generally greater ground integrity. I’ve found the bootleg function most useful in older buildings with box to yolk grounding or systems grounded through conduit. No matter what- you cant use the sure test as the gospel… consider it more as a gauge. Either way- who doesn’t LOVE to find those buggers!

I have a question and I think this has been brought up before. I used my tester on a GFI and it didn’t trip, when I pushed the button it did, this was in a house that was 20 years old and had other GFIs that where stuck in the open position.

What’s the calibration date on your GFCI tester? It’s probably reasonable to say that the GFCI device itself was defective, and not your tester. I just have a problem with folks that condemn equipment without calibrated test equipment. From the standpoint of an electrician, I’d encourage you to report this as a device that “may” have a problem, so that you don’t look foolish in case it’s fine. There is equipment on the market that will test the exact trip point, in milliamps, at which a GFCI trips.

That’s how I wrote it in my report, there where no GFIs at the kitchen sink and that was included as well.

I’ve test it out in other receptacles at my house and it checks out so I’m thinking it was the outlet.

I have both the more expensive Ideal Suretest tester and the much less expensive Commercial Electric one that I had bought when I first started out. Usually I use the Suretest, but there are times when the other one comes in handy because of its smaller size. When I have come across GFCI’s that don’t trip properly using the Suretest, I try it with the Commercial Electric to make sure its not my equipment that is faulty but the receptacle itself.


Chris, That’s a good point, I’ll get a back up tester to keep on hand.

Thanks, Pete



The SureTest does this. . .