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Rayl82 said:
Power is always going to take the fastest thought to ground. That's why if you insulate yourself from ground properly you can tuch individual live conductors with no repercussions.... The case ground and ground to windings are generally the same and by adding the ground rod you've effectively created a shorter path to ground. And the breaker doesn't see it so it trips as if there were a problem.

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Ray, hopefully you did open the link that George Stolz posted in response to your misunderstanding/confusion regarding the difference between earth grounding and equipment bonding. Not to pile it on here, but it is absolutely essential that all personnel who will be servicing electrical systems (especially those under 600 volts) understand that the gec (grounding electrode conductor) and the egc (equipment grounding conductor) are two totally different things and perform vastly different functions. The gec (in most cases a ground rod) does NOT provide shock protection when exposed metal parts become energized because all current (including fault current) is always trying to find the the least resistant path back to the source (poco tranny) and the earth is NOT suitable as such a path. Ground rods are for the most part useless and the only plausible benefit one might get from a ground rod would be from lightning/and or power surges (think tree falls on primary-primary hits secondary etc.) and even then its only a sometimes thing. The egc on the other hand, is meant to provide protection against exposed metal parts which may become energized as it is bonded to the source through the service neutral, which is of course a direct connection between those egcs and the poco tranny. The earth isn't a good return path for fault current because it almost always is too resistant. Lets assume you have 10 ohms of resistance between an unbonded standard 8'ground rod and the source- doesn't sound like much does it. Now apply 120 to the rod-120 vac / 10 ohms= 12 amps- not enough to trip even a 15 amp ocpd. Now think 120 vac to that egc bonded to that service neutral which in many cases will an ohm or less- 120 vac/ 1 ohm=120 amps-more than enough to quickly trip that same ocpd. Sorry for the long windedness, but grounding and bonding is one of the most misunderstood aspects of our trade, and one that has gotten people hurt and killed.
 
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user 100 said:
Ray, hopefully you did open the link that George Stolz posted in response to your misunderstanding/confusion regarding the difference between earth grounding and equipment bonding. Not to pile it on here, but it is absolutely essential that all personnel who will be servicing electrical systems (especially those under 600 volts) understand that the gec (grounding electrode conductor) and the egc (equipment grounding conductor) are two totally different things and perform vastly different functions. The gec (in most cases a ground rod) does NOT provide shock protection when exposed metal parts become energized because all current (including fault current) is always trying to find the the least resistant path back to the source (poco tranny) and the earth is NOT suitable as such a path. Ground rods are for the most part useless and the only plausible benefit one might get from a ground rod would be from lightning/and or power surges (think tree falls on primary-primary hits secondary etc.) and even then its only a sometimes thing. The egc on the other hand, is meant to provide protection against exposed metal parts which may become energized as it is bonded to the source through the service neutral, which is of course a direct connection between those egcs and the poco tranny. The earth isn't a good return path for fault current because it almost always is too resistant. Lets assume you have 10 ohms of resistance between an unbonded standard 8'ground rod and the source- doesn't sound like much does it. Now apply 120 to the rod-120 vac / 10 ohms= 12 amps- not enough to trip even a 15 amp ocpd. Now think 120 vac to that egc bonded to that service neutral which in many cases will an ohm or less- 120 vac/ 1 ohm=120 amps-more than enough to quickly trip that same ocpd. Sorry for the long windedness, but grounding and bonding is one of the most misunderstood aspects of our trade, and one that has gotten people hurt and killed.
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Yes I did open the link and I thanked him for the info. We are always learning.. I tried to edit my posting or even remove it, but was unable to do so. I was assuming that like a arc fault breaker the natural return is monitored by the breaker and when a closer ground path is made the breaker trips. Not to say that is the complete reason the system described is faulting. There is probably still an issue with the circuit like missing wires in the original installation.

The grounded conductor and the grounding conductor are to remain separate until the service entrance panel were water, gas, rods, and slab are all connected to the service ground which has a jumper to the natural bus bar.
 
user 100 said:
Ray, hopefully you did open the link that George Stolz posted in response to your misunderstanding/confusion regarding the difference between earth grounding and equipment bonding. Not to pile it on here, but it is absolutely essential that all personnel who will be servicing electrical systems (especially those under 600 volts) understand that the gec (grounding electrode conductor) and the egc (equipment grounding conductor) are two totally different things and perform vastly different functions. The gec (in most cases a ground rod) does NOT provide shock protection when exposed metal parts become energized because all current (including fault current) is always trying to find the the least resistant path back to the source (poco tranny) and the earth is NOT suitable as such a path. Ground rods are for the most part useless and the only plausible benefit one might get from a ground rod would be from lightning/and or power surges (think tree falls on primary-primary hits secondary etc.) and even then its only a sometimes thing. The egc on the other hand, is meant to provide protection against exposed metal parts which may become energized as it is bonded to the source through the service neutral, which is of course a direct connection between those egcs and the poco tranny. The earth isn't a good return path for fault current because it almost always is too resistant. Lets assume you have 10 ohms of resistance between an unbonded standard 8'ground rod and the source- doesn't sound like much does it. Now apply 120 to the rod-120 vac / 10 ohms= 12 amps- not enough to trip even a 15 amp ocpd. Now think 120 vac to that egc bonded to that service neutral which in many cases will an ohm or less- 120 vac/ 1 ohm=120 amps-more than enough to quickly trip that same ocpd. Sorry for the long windedness, but grounding and bonding is one of the most misunderstood aspects of our trade, and one that has gotten people hurt and killed.
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Not sure why this didn't post last night. But thank you for the information, it is a good read.
 
Rayl82 said:
Not sure why this didn't post last night. But thank you for the information, it is a good read.
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Your welcome ray. Your right- we are all still learning and you will find that this site, along with electrician talk and electrical contractor.net (many of the members here are also members of those forums) is a good start that will provide almost unlimited resources and knowledge concerning all areas of the electrical trade due to the experienced professionals who post here. I would strongly recommend these sites to apprentices or any electrician looking for understanding on any electrically related topic. If you don't know don't be afraid to ask-someone will help, and almost no question is too stupid. The link Stolz posted needs to be required reading for electricians and once read needs to be read again. Welcome to the forum!
 
Does the pool have the code required equipotential bonding system and was a jumper from that system connected to the old pump motor?
 
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