Two Remote Ground Electrodes

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electrofelon said:
Is this a typical metal pole on a concrete base? IF so isnt it already earthed?
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Some of them are on concrete base but some of them are directly driven to the ground for a couple feet.
In either case, there is a ground electrode fir grounding the pole and lights and other electronic equipment on the pole.
 
Sometimes it is the lighting fixtures and sometimes it is a breaker to feed electronic equipment.
Does it make a difference?
 
Electriman said:
Sometimes it is the lighting fixtures and sometimes it is a breaker to feed electronic equipment.
Does it make a difference?
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bThe difference:

If the conductors feed only a load, they're a branch circuit, and no electrode is required.

If the conductors feed a breaker panel, they're a feeder; the panel triggers the electrode.
 
We’re all over the place, the circuit conductors you have ran for the light poles. Do they go directly to the light poles and terminate?

Do they go into a sub panel that from there feeds the light poles?

What is your set up?

Either way the he’s working with a customer that thinks as many do and believes a ground rod is a vital role at a big pole probably connected to a big chunk of concrete and steel with way more surface area than a 5/8” rod.

Either way wether it’s a non-needed “auxiliary electrode” or a needed separate structure electrode for a sub panel. Wouldn’t the circuit EGC be sufficient for bonding the electrodes back to the service electrodes.?
 
Electriman said:
Some of them are on concrete base but some of them are directly driven to the ground for a couple feet.
In either case, there is a ground electrode fir grounding the pole and lights and other electronic equipment on the pole.
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I may have missed something.
Is there a ground wire from the panel to the lighting pole? Or are you using the ground rod inlue of the ground wire?
 
They were pretty standard back in the day, Mike Holt has a whole video on why not to do it, but that’s what they did. Anyone else remember why they had such a penchant for doing this back then? Almost seems like a waste of money and time resources.


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Electriman said:
Yes. the EGC is going with the to lighting pole.
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It is an auxiliary electrode.

250.54 Auxiliary Grounding Electrodes One or more grounding electrodes shall be permitted to be connected to the equipment grounding conductors specified in 250.118 and shall not be required to comply with the electrode bonding requirements of 250.50 or 250.53(C).

This is what silly equipment manufacturers like CNC machines require. They do not quite understand how to establish a new ground reference point using a separately derived system. You can bond the EGC to auxiliary electrodes and there are no requirements to follow other than the EGC must be run with circuit conductors used to clear a fault.

You can use Cat-5 cable or baling wire for the bonding jumper to the rod.

FWIW at 800 feet distance, the voltage drop between Neutral and Ground will be excessive and can wreak havoc on filters and sensitive electronics. It is a misguided attempt to reference the EGC to earth. The best way to accomplish this is to treat the circuit like a service only running line and neutral so a new ground reference is created when ground and neutral are bonded. Codes use to allow that method, today would take an isolation transformer configured SDS.
 
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dereckbc said:
It is an auxiliary electrode.

250.54 Auxiliary Grounding Electrodes One or more grounding electrodes shall be permitted to be connected to the equipment grounding conductors specified in 250.118 and shall not be required to comply with the electrode bonding requirements of 250.50 or 250.53(C).

This is what silly equipment manufacturers like CNC machines require. They do not quite understand how to establish a new ground reference point using a separately derived system. You can bond the EGC to auxiliary electrodes and there are no requirements to follow other than the EGC must be run with circuit conductors used to clear a fault.

You can use Cat-5 cable or baling wire for the bonding jumper to the rod.

FWIW at 800 feet distance, the voltage drop between Neutral and Ground will be excessive and can wreak havoc on filters and sensitive electronics. It is a misguided attempt to reference the EGC to earth. The best way to accomplish this is to treat the circuit like a service only running line and neutral so a new ground reference is created when ground and neutral are bonded. Codes use to allow that method, today would take an isolation transformer configured SDS.
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True. Isolation transformers are used on lots of medical equipment. We used them when I worked factory. We had X-rays and spectrometers.

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infinity said:
The way I'm reading the OP there is no "structure" electrode at the pole and with a single circuit one is not required. That leaves a ground rod for lightning protection at the pole or can we call it an auxiliary electrode? Come to think of it there seems to be no lightning protection system at the pole.
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Call it an auxiliary electrode and stop misleading people into thinking that they are installing meaningful lightning protection if they are not doing so in accordance with a lightning protection code or a design by a lightning protection professional.
 
DrSparks said:
True. Isolation transformers are used on lots of medical equipment. We used them when I worked factory. We had X-rays and spectrometers.

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not trying to be a smart alec but an x ray not used for medical purposes is not medical equipment. But yes some items with sensitive electronics seem to want such isolation and their own grounding electrodes and "supplemental electrodes" are permitted in code. Isolation however generally means you are creating a completely separate ungrounded system. Though non current carrying components on an ungrounded systems still are supposed to be bonded together and to the GEC in some way or another.
 
tom baker said:
We will be dead and gone and there still will be ground rods installed at lighting poles that serve no purpose.
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somehow the electrons know there is only a single branch circuit going to the pole or a shed so they behave, unlike if there is a feeder going there. then they will misbehave unless there is a ground rod present, which makes them behave.
 
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