Bonding water and gas lines at the meter panel.

[losmolinos2016]

Hi.

I am new to the forum so please forgive me if I raise a question that was raised in the past.
We are bonding water and gas lines to the neutral/ground bar in the meter panel as per local requirements.
The way I see it if the service drop from the power co. has a problem on the grounded line we are introducing line voltage
on everything that is bonded, what am I missing?.

 

[don_resqcapt19]

Hi.

I am new to the forum so please forgive me if I raise a question that was raised in the past.
We are bonding water and gas lines to the neutral/ground bar in the meter panel as per local requirements.
The way I see it if the service drop from the power co. has a problem on the grounded line we are introducing line voltage
on everything that is bonded, what am I missing?.

You are not missing anything and that happens no matter where the bond is made.

 

[losmolinos2016]

Bonding.

Bonding.

Then why are we bonding the water and gas pipes at all, if those pipes are not, the way I see it, the likelihood of getting electrocuted is smaller in the event that the grounded conductor from the power co. fails.

 

[ActionDave]

Then why are we bonding the water and gas pipes at all, if those pipes are not, the way I see it, the likelihood of getting electrocuted is smaller in the event that the grounded conductor from the power co. fails.

Because if they become energized from a fault we want the overcurrent protection to trip rather than sitting there waiting to give somebody a shock.

 

[tom baker]

Typically gas lines are not required to be bonded. 250.104 allows the egc for the equipment connected to the gas line to do the bonding.

 

[jeffgreef]

Losmolinos- the reason is that most or all current takes the shortest, lowest impedance path back to the transformer. If there is a short to the utility neutral, little if any current will go toward the house, it's all going to go the other way to the transformer. But if one or another EGC is somehow connected back to the transformer with a low impedance path, say by touching the GEC coming down the utility pole from the transformer, then yes, that EGC would take some current before the transformer fuse blew. This is why you want the ground/neutral bond as close to the transformer as possible, so that path is more likely the path that all or most current will take in a fault event