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Earth Ground Resistance Test Houston Texas

Earth Ground Resistance Test Houston Texas

Wayne Rogers This is a very serious issue. A Gross misunderstanding of the National Electrical Code force many violations to exist in New Home Construction. The finger pressing the test button, is the finger of a very upset home owner. He now knows his electrical system is not protected by a proper electrical ground system.

We know many Electrical Inspectors and Builders, working as the "Authority Having Jurisdiction", are requiring Electricians and Electrical Contractors to install this method of service-entrance grounding. They think this method is an example of the Ufer ground method, developed during world war II, but they are very wrong. The installation they require is not what Mr. Ufer demonstrated to be a successful grounding method. I have included a picture of the test meter, so you can see the readings close up. I hope this information will be of use to you. We cannot allow the uninformed electrical trade to continue placing unsuspecting home owners in grave danger of cracked slabs, burns, and electrical shock or electrocution.

Good Day All,
     Yesterday I conducted an "Earth Ground Resistance Test" for a client at his new home (7 months old), because he was having electrical problems that the Electrical Contractor could not fix. The client has endured the Electrician making numerous go backs on this home. A Home Inspector here in Houston referred him to me. I conducted an electrical inspection and found many Code violations.

As a part of my inspection I used a Biddle Ground Resistance Tester Model 3620 to test the ground resistance of the So Called "Concrete Encased Electrode". The concrete slab and enclosed steel was installed on top of a "Vapor Barrier". Therefore "direct contact with earth" was not made to the earth as required by the National Electrical Code to QUALIFY as a "Concrete Encased Electrode". This type of installation is typical to all new homes in the greater Houston, TX Area.

I connected the earth ground tester and asked the client to push the test button. The reading was a tad under 200 Ohms. I will show you the photographed test below. The National Electrical Code, for many years, has used the value of 25 Ohms or less as a bench mark for the earth ground test. 200 Ohms is totally unacceptable.
Ground Resistance Tester MODEL 3620. The installation tested, is the grounding method Electricians now install to Ground the Electrical Service-Entrance of your home. A proper earth ground is necessary to protect your home and equipment from lightning and other destructive electrical events. This method is often called the Ufer Ground Method or "Concrete Encased Electrode". The National Electrical Code describes the highest resistance to ground should be not more than 25 Ohms to ground, as a measure of the quality of your installed "Grounding Electrode". (People in the electrical field know what I am saying.) As you can see by the reading of this actual test, performed on Monday, April 4, 2016 at a NEW HOME, the resistance is tested at 200 Ohms of resistance to ground. This measurement is a violation of the National Electrical Code, when the maximum resistance should NOT be over 25 Ohms. This grounding method is most likely the method used in your New Home. Have your "Earth Ground Resistance" tested, with the proper tester and a QUALIFIED ELECTRICIAN.

Wayne Rogers Electrical Consultant, Master Electrician

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