Grounding I beams on doublewide

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Ballvalve

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Pretty much automatic already, unless we are discussing power to a 240v well in conduit that will never use a neutral anyway.

When later the pumphouse gets built and they want a heater and a light, the neutral would be welcome. Saw a lot of grounds as neutrals in that situation.
 

Jetlag

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Pretty much automatic already, unless we are discussing power to a 240v well in conduit that will never use a neutral anyway.

When later the pumphouse gets built and they want a heater and a light, the neutral would be welcome. Saw a lot of grounds as neutrals in that situation.

If you have the power coming in to a lighting outlet , you can no longer run a 14/2 or 12/2 switch leg down to the switch , you must run 12/3 or 14/3 and leave an unused neutral in the switch box . I know what you mean on the pump houses 10/2 w/g was all all people used to use . I ve seen them drive a ground rod and bond it to a small panel in the pump house and say ok that 10/2 w/g is my power co and I grounded it just like they do . so whats wrong with connecting a 110 circuit ? . I had to admit two hots and a ground is two hots and a ground not matter how you get it .
 

JWelectric

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I know what you mean on the pump houses 10/2 w/g was all all people used to use . I ve seen them drive a ground rod and bond it to a small panel in the pump house and say ok that 10/2 w/g is my power co and I grounded it just like they do . so whats wrong with connecting a 110 circuit ? . I had to admit two hots and a ground is two hots and a ground not matter how you get it .

But their statement of “two hots and a ground is two hots and a ground not matter how you get it†is incorrect.

What the power company supplies to a dwelling is two hots and a grounded conductor. The definition of ground by the NEC is simply, “earth†as shown here
Ground. The earth.
Now couple this with the requirement found in 250.56 concerning the resistance of a rod and using Ohm’s Law we can see that two hots and a ground equals not much of anythihg.
250.56 Resistance of Rod, Pipe, and Plate Electrodes. A single electrode consisting of a rod, pipe, or plate that does not have a resistance to ground of 25 ohms or less shall be augmented by one additional electrode of any of the types specified by 250.52(A)(4) through (A)(8).

Using E=IXR and the 25 ohms mentioned above we can see that at 120 volts the earth would only carry 4.8 amps. In most cases connecting this 100 watt bulb to a 120 volt circuit using ground as a return path and the bulb will not burn.

When connecting this two conductor with ground to a 120 volt circuit what happens is the equipment grounding conductor is elevated to a potential of 120 volts. Anything connected to this equipment grounding conductor becomes energized to a potential of 120 volts.

The purpose of the equipment grounding conductor is outlined in 250.4 which states
(2) Grounding of Electrical Equipment. Normally non–current-carrying conductive materials enclosing electrical conductors or equipment, or forming part of such equipment, shall be connected to earth so as to limit the voltage to ground on these materials.
but what has happened is the voltage has been elevated and not limited.

Using this two conductor with ground to connect a 120 volt load to a 240 volt circuit using the EGC as the grounded neutral conductor in no way resembles what the power company delivers to a dwelling unit. It is nothing less than a death trap that will end up hurting or killing someone. The only question is when.
 

Jetlag

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But their statement of “two hots and a ground is two hots and a ground not matter how you get it” is incorrect.

What the power company supplies to a dwelling is two hots and a grounded conductor. The definition of ground by the NEC is simply, “earth” as shown here
Now couple this with the requirement found in 250.56 concerning the resistance of a rod and using Ohm’s Law we can see that two hots and a ground equals not much of anythihg.


Using E=IXR and the 25 ohms mentioned above we can see that at 120 volts the earth would only carry 4.8 amps. In most cases connecting this 100 watt bulb to a 120 volt circuit using ground as a return path and the bulb will not burn.

When connecting this two conductor with ground to a 120 volt circuit what happens is the equipment grounding conductor is elevated to a potential of 120 volts. Anything connected to this equipment grounding conductor becomes energized to a potential of 120 volts.

The purpose of the equipment grounding conductor is outlined in 250.4 which states but what has happened is the voltage has been elevated and not limited.

Using this two conductor with ground to connect a 120 volt load to a 240 volt circuit using the EGC as the grounded neutral conductor in no way resembles what the power company delivers to a dwelling unit. It is nothing less than a death trap that will end up hurting or killing someone. The only question is when.

I never said I would do it but connected that way the bare ground becomes the grounded conductor back to the house panel . As far as it not being insulated their argument was the power co wraps their hots around the bare messenger wire which is grounded current carrying conductor .
 

Jetlag

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I forgot to say they used a GFCI receptacle in the pump house and protected the light with the GFCI feed out terminals . As far the power co neutral it is grounded at the meter or disconnect to the ground rod . Same as the panel at pump house .
 

JWelectric

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No my friend there is no grounded neutral at the pump house.

The bare wire that the power company is supplying is almost like the chassis connection on your car except the car is not grounded or connected to earth. The bare wire that the power company connects to earth at the transformer and the electrical contractor reconnects to earth at the service is one of the conductors that completes the path back to the transformer.

The bare wire at the pump house is an “Equipment Grounding Conductor” it is not a grounded neutral conductor and for someone to compare it to what the power company does shows a complete lack of knowledge of an electrical system.

This Equipment Grounding Conductor is to never have current on it. Should it have current on it this current would return to the grounded neutral and complete the path back to the transformer through the main bonding jumper in the service equipment and open the overcurrent device protecting the conductors ran with the EGC. The power company uses the earth as their equipment grounding conductor. With as much push as is delivered to the primary of the poco (power company) the resistance of earth can be overcome. Using E=IxR we can see that at 25 ohms as required by 250.56 of the NEC can be overcome by 7200 volts. Most transformers for residential dwellings will be protect by no more than 10 amps so 7200 volts divided by 25 ohms equals 288 amps which would be more than enough to open the primary of the transformer.

It is not a question of will someone get hurt but instead it is a question of WHEN will someone get hurt or killed by this connection at the pump house. Any one who would make a connection such as this should be prosecuted in a court of law for endangering the life of the public.
 
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