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How many electricians feel grounding a service is necessary for operation, not bonding, but grounding to an electrode?

It seems that some electricians feel a connection to earth is a necessity for an AC power system to operate.
 

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Well I’ll go first, I get a little nervous without driving a few rods. I go overboard on my grounding on r-mix plants, in some fashion due to the silo makes a real big target for lightning.
ETA as far as operating, no, safety in my rough and tumble world of concrete, I will say yeah. A few copper clad rods flogged in the ground are cheap and easy.
 

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How many electricians feel grounding a service is necessary for operation, not bonding, but grounding to an electrode?

It seems that some electricians feel a connection to earth is a necessity for an AC power system to operate.
I'm certain that I have always know that the system will operate without grounding.
 

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Discussion Starter #4
Well I’ll go first, I get a little nervous without driving a few rods. I go overboard on my grounding on r-mix plants, in some fashion due to the silo makes a real big target for lightning.
ETA as far as operating, no, safety in my rough and tumble world of concrete, I will say yeah. A few copper clad rods flogged in the ground are cheap and easy.
100% agree with that aspect of grounding.
 

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Brian you should have put a finer point on it. Does connecting to a ground rod help or cause breakers to trip? No. Will connecting to the ground rod help with lightning protection, voltage stabilization, & cause the POCO fuse to blow if the xfmr shorts to the secondary? I believe so.
 
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How many electricians feel grounding a service is necessary for operation, not bonding, but grounding to an electrode?

It seems that some electricians feel a connection to earth is a necessity for an AC power system to operate.
Yes, for voltage stability as noted in both NEC 250.4(A)(1) and CEC 10-002 a).

:D
 

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What the heck, there's no ducking smilie?
 

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How many electricians feel grounding a service is necessary for operation, not bonding, but grounding to an electrode?

It seems that some electricians feel a connection to earth is a necessity for an AC power system to operate.
If that was true, then how could we have ungrounded systems, resistance and impedance grounded systems?
 

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If you have no grounding electrode, what happens in an open neutral situation?
Well, depending on where the neutral is broken, and the condition of your ground conductors, you might have neutral current on both a portion of your neutral and your ground conductor.

But that's not normal operation of your electrical system.
 

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Please explain how driving an electrode provides voltage stability?
Unless you have a ground connection to the neutral all you have is a center tap, not a neutral.
 
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Unless you have a ground connection to the neutral all you have is a center tap, not a neutral.
The way the NEC defines neutral, the center tap / center of wye is a neutral point whether or not it is grounded.

Neutral Point. The common point on a wye-connection in a polyphase system or midpoint on a single-phase, 3-wire system, or midpoint of a single-phase portion of a 3-phase delta system, or a midpoint of a 3-wire, direct-current system. (CMP-5) Informational Note: At the neutral point of the system, the vectorial sum of the nominal voltages from all other phases within the system that utilize the neutral, with respect to the neutral point, is zero potential.
 

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The way the NEC defines neutral, the center tap / center of wye is a neutral point whether or not it is grounded.
Correct. And the only way to ensure that center point/neutral maintains 0V in relation to ground is to connect it to said ground.

Current just doesn't magically break all the rules of electricity when flowing on a neutral conductor. A neutral must have a voltage on it for current to flow however small that voltage might be. Grounding the neutral ensures it is at ground potential.
 
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Discussion Starter #18
Unless you have a ground connection to the neutral all you have is a center tap, not a neutral.
You do not need a ground for a neutral. Take a Wye transformer, Where you have removed the neutral to ground bond and test phase, neutral current then do a zero sequence measurement. You will see the neutral is working like a neutral.
 

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Discussion Starter #19
Correct. And the only way to ensure that center point/neutral maintains 0V in relation to ground is to connect it to said ground.

Current just doesn't magically break all the rules of electricity when flowing on a neutral conductor. A neutral must have a voltage on it for current to flow however small that voltage might be. Grounding the neutral ensures it is at ground potential.
That does not make it a neutral, and the system will operate without this neutral ground bond. And even when you do bond it, you do not need a grounding electrode for normal operation.
 

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That does not make it a neutral, and the system will operate without this neutral ground bond. And even when you do bond it, you do not need a grounding electrode for normal operation.
FWIW
The ground rod driven at the service and connected to the neutral extends the POCO ground system from the pole. The Brits do it differently. IIRC they run a hot, neutral & ground to the service from the POCO xfmr.
 
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