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Photos of how I grounded an older home's TV and telephone services.   Click for The Home Page

Photos of Grounding and Bonding for Power, Telephone, and TV

Dear Mr. Electrician: My neighbor was blown out of her chair when lightning hit her TV.  How can I prevent this from happening to me?

Answer:
Basically everything needs to be properly grounded and bonded in such a manner as to provide a good direct path for lightning to flow to the earth.  The photos below depict an actual job of mine correcting the grounding for a 1940's single family detached house.  Article 250 in the National Electrical Code concerns grounding and bonding.  Some relevant sections are: 250.8, 250.52, 250.90, 250.94, 250.104.  Also read article 800.100 on grounding communication circuits and 820.100 which concerns the grounding of cable TV systems.
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Very old grounding and bonding conductors that were installed for this Cable TV and Telephone service
 
This is how I found the TV and telephone lines grounded.  It turns out that this pipe was not connected to anything.  It was in the ground several inches and contained a cut off electrical cable, the remains of which is protruding from the pipe.  Needless to say, this would not be adequate protection if lightning were to strike.  NEXT

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Close shot of old ground wire connection to a broken pipe
 
This was the existing ground connection for the cable TV service to the house.  I ran a new number 10 copper wire to the grounding electrode conductor which was connected to the water pipe inside of the house. NEXT

Click for the "After" photo

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The old ground wire for the cable TV service

Here is the newer telephone demarcation box with a ground connection that is not very good.  NEXT

Click to see the new ground bonding conductor for this.

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Close shot of the interior of the telephone demarcation box.
 

The arrow indicates the existing grounding terminal on the original telephone demarcation point.  It was still active with it now being fed from the new outside telephone demarcation box.  The existing ground wire was attached to a water pipe at a sink in the back of the basement instead of the water main near the water meter.  NEXT

Click to see the "After" photo

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Close shot of the old telephone demarcation block.
 
Inside of the main electrical panel.

Inside of the main electrical panel.  The arrow points to the grounding electrode conductor.  NEXT

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A close shot of the grounding electrode conductor as it enters the main electrical panel.  NEXT

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Close shot of the grounding electrode conductor as it enters the main electrical panel
 

Here is a close shot of the neutral and ground terminal bar inside of the main electrical panel for the entire house.  The arrows point to the grounding electrode conductor and the terminal screw where it is connected.  NEXT

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Close shot of the neutral and ground terminal bar inside of a main electrical panel.  The grounding electrode conductor is highlighted with arrows.
 

This is the old water main with the old grounding electrode conductor still attached.  The old water main is not connected to any interior metal piping.  NEXT

Click to see the new clamp

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Close shot of old water main with old water pipe ground clamp and old armored grounding electrode conductor.
 

This is the new water main just after it enters the basement.  This is also the new and current grounding electrode connection to the main water service.  NEXT

Click to see the new clamp

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Close of the current water pipe ground connection with an old rusted ground clamp.
 

This photo depicts the water meter and the bonding jumper connection points on each side of the meter.  You can also see the old water main.  NEXT

Click to see everything bonded together

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Water meter without any bonding jumper
 

I cleaned the water pipe with  emery clothEmery Cloth to get it ready for the new water pipe ground clamp   NEXT

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Cleaned section of water pipe ready to accept a new ground clamp
 
Close shot of water meter bonding jumper ground clamp and wire.
 

The same pipe section as above, but with a new water pipe ground clamp and wire attached.  NEXT

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This is how a water meter should be jumped out with a ground bonding jumper.  #6 copper wire is sufficient, but it is #4 in the picture.  The purpose of the water meter bonding jumper is to maintain grounding continuity on the water pipes in case the current brass water meter is ever changed to a plastic meter.  NEXT

Click to see the "Before" photo

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Water meter with bonding jumper installed on each side of it
 

The new  water pipe ground clamp connecting the grounding electrode conductor to the water main just after it enters the basement.  NEXT

Click to see old ground clamp

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Close shot of new water main with a new ground clamp.
 

The cable TV and telephone demarcation points have now been properly grounded to protect from lightning strikes.  NEXT

Click to see the "Before" picture

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Telephone and Cable TV demarcation points with proper grounding to protect from lightning strikes
 

The new number ten green, copper, ground bonding conductor was brought into the house via a new drilled hole because there were none existing nearby.  NEXT

Click for the "Before" photo

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Close shot of the new ground connection for the cable TV service.
 
The new number ten green, copper, ground bonding conductor is connected to the ground terminal screw inside of the main telephone demarcation box for the house.  I installed the new wire through the existing phone wire tube to avoid another hole in the wall.  NEXT

Click to see the "Before" picture.

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Close shot of the new telephone demarcation box with a new ground wire connection.
 
I clamped the TV and telephone ground bond wires to the grounding electrode conductor that is connected to the water main pipe at one end and to the main electrical panel at the other end. 

As an alternative, I could have installed an Intersystem Bonding Termination as required in article 250.94 of the National Electrical Code.  All of the ground wires would then just terminate together there. NEXT

Click to see my photos of an intersystem bonding termination

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Close shot of the ground wires clamped together.
 

In addition to the other bonding and grounding, I also bonded all of the interior metal piping which includes the cold water pipe to the hot water pipe and the gas pipe as required in article 250.104 (A) and (B) of the National Electrical Code .  If this house contained a hot water baseboard heating system with metal pipes, those would have to be bonded to the cold water pipe as well.  It is very convenient to bond all three pipes at the water heater and they are accessible for the inspector to see.  Please note that some areas of the country may not permit the gas pipe to be bonded.  You should check with your local building department.  NEXT

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Water heater with bonding jumper installed.
 

Here's a close shot of the same water heater bond.  Each pipe was cleaned with emery clothEmery Cloth before the ground clamps were attached.

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Bonding jumper between cold water, hot water, and gas pipe at the water heater

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Updated December 15, 2015

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