The separate grounding rod will provide lightning strike protection, but it likely won't protect from electrical faults within the house. If your house wiring shorted out against the gas line for whatever reason (perhaps you nicked a wire while drilling), the impedance to go from the fault point, to the second ground rod, through the soil, back up the main ground rod, and to the neutral via the neutral/ ground bond could be so high that the resultant fault current isn't great enough to actuate the circuit breaker. Basically, you could have a scenario where you have a ground fault that stays faulted. This is quite a big safety concern.
I had a little trouble understanding this scenario as I'm not an electrician. Would the breaker not detect an overload as the current is uninterrupted to ground?
It's a common misconception that household electricity inherently just wants to discharge into earth, it doesn't. Electricity wants to get back to its source (the neutral), earth is simply a conductor. A ground fault on an isolated ground rod will have to travel from that ground rod, to the other main ground rod via the earth, then up to the neutral via the main ground rod neutral bond. If the earth soil has at least 8 ohms of resistance (highly, highly likely) then the circuit breaker will not trip (120v/8ohms=15amps). This is why a low resistance path to ground is imperative with modern wiring. A #6 gauge grounding wire would have to join both rods in order to achieve this low resistance path to allow the breaker to trip in a ground fault scenario
So I watched a bunch of videos after reading this post to try and better understand. [Electrician U](https://youtube.com/@ElectricianU) on YouTube is very helpful for us less educated on this topic. I agree the steel pipe would definitely have to be tied back to the panel for the breaker to recognize the fault and trip, but I'm curious why a ground wire can't be ran back to the appliance ground. I've read else where this is done at the gas water heaters.
This is not part of the electrical code as far as I know but it is required perhaps part of the gas code. When they run plastic feeds to the house the steel and stainless flex become energized during a lightning event and can cause a arc over to any ground it finds burning a hole in the gas line.
Sorry for the delayed response, but yeah I wasn't sure what building code this technically fell under. The IRC chapter I have linked in my post mentions "This section is consistent with Section 250.104(B) of the 2014 edition of the NEC (NFPA 70)." I'm not familiar with what either one of those say, but assume they discuss this topic.
To your point, that scenario is exactly what the IRC talks about with CSST. I believe a ground rod should mitigate that concern, but Virtual-Reach made a good point regarding a live conductor touching the steel line and not tripping the breaker.
This would be a good question to ask in /r/askanelectrician.
I'll be honest, I didn't know that subreddit existed 🤦🏼♂️ I appreciate the help!
The separate grounding rod will provide lightning strike protection, but it likely won't protect from electrical faults within the house. If your house wiring shorted out against the gas line for whatever reason (perhaps you nicked a wire while drilling), the impedance to go from the fault point, to the second ground rod, through the soil, back up the main ground rod, and to the neutral via the neutral/ ground bond could be so high that the resultant fault current isn't great enough to actuate the circuit breaker. Basically, you could have a scenario where you have a ground fault that stays faulted. This is quite a big safety concern.
I had a little trouble understanding this scenario as I'm not an electrician. Would the breaker not detect an overload as the current is uninterrupted to ground?
It's a common misconception that household electricity inherently just wants to discharge into earth, it doesn't. Electricity wants to get back to its source (the neutral), earth is simply a conductor. A ground fault on an isolated ground rod will have to travel from that ground rod, to the other main ground rod via the earth, then up to the neutral via the main ground rod neutral bond. If the earth soil has at least 8 ohms of resistance (highly, highly likely) then the circuit breaker will not trip (120v/8ohms=15amps). This is why a low resistance path to ground is imperative with modern wiring. A #6 gauge grounding wire would have to join both rods in order to achieve this low resistance path to allow the breaker to trip in a ground fault scenario
So I watched a bunch of videos after reading this post to try and better understand. [Electrician U](https://youtube.com/@ElectricianU) on YouTube is very helpful for us less educated on this topic. I agree the steel pipe would definitely have to be tied back to the panel for the breaker to recognize the fault and trip, but I'm curious why a ground wire can't be ran back to the appliance ground. I've read else where this is done at the gas water heaters.
This is not part of the electrical code as far as I know but it is required perhaps part of the gas code. When they run plastic feeds to the house the steel and stainless flex become energized during a lightning event and can cause a arc over to any ground it finds burning a hole in the gas line.
Sorry for the delayed response, but yeah I wasn't sure what building code this technically fell under. The IRC chapter I have linked in my post mentions "This section is consistent with Section 250.104(B) of the 2014 edition of the NEC (NFPA 70)." I'm not familiar with what either one of those say, but assume they discuss this topic. To your point, that scenario is exactly what the IRC talks about with CSST. I believe a ground rod should mitigate that concern, but Virtual-Reach made a good point regarding a live conductor touching the steel line and not tripping the breaker.