- Occupation
- Licensed Electrician
Are you one of those guys who throws his ground rods in a trench instead of driving them?
Meter has rigid conduit to disconnect
- Thread starter cduke103
- Start date
- Status
DrSparks
The Everlasting Know-it-all!
- Location
- Madison, WI, USA
- Occupation
- Master Electrician and General Contractor
Also I don't know how many times I seen the Earth ground symbol on schematics rather than the chassis ground symbol
Sent from my A574BL using Tapatalk
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
...which brings us back to the point that Rob and Ethan made earlier; all levels of experience frequent this forum and it is important to use proper terminology to avoid confusing people. When you speak of a "zero voltage reference point" it propagates the myth that electricity is seeking the earth, whether EEs misuse the term or not. It's akin to saying the green finish on a main bonding jumper screw is pertinent to clearing a ground fault.
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
I'm way too lazy to dig a 30" deep trench, I just cut them about 9" long and hammer the end good.
DrSparks
The Everlasting Know-it-all!
- Location
- Madison, WI, USA
- Occupation
- Master Electrician and General Contractor
I think the definition from Wikipedia explains it best:
In*electrical engineering,*ground*or*earth*is the reference point in an*electrical circuit*from which voltages are measured, a common return path for*electric current, or a direct physical connection to the*Earth.
Electrical circuits may be connected to ground (earth) for several reasons. In*mains*powered equipment, exposed metal parts are connected to ground so that if, due to any fault conditions, a "Line" supply voltage connection occurs to any such conductive parts, the current flow will then be such that any protective equipment installed for either overload or "leakage" protection will operate and disconnect the "Line" voltage. This is done to prevent harm resulting to the user from coming in contact with any such dangerous voltage in a situation where the user may, at the same time, also come in contact with an object at ground/earth potential. In electrical power distribution systems, a Protective Earth (PE) conductor is an essential part of the safety provided by the*earthing system.
Connection to ground also limits the build-up of*static electricity*when handling flammable products or*electrostatic-sensitive devices. In some*telegraph*and*power transmission*circuits, the earth itself can be used as one*conductor*of the circuit, saving the cost of installing a separate return conductor (see*single-wire earth return).
For measurement purposes, the Earth serves as a (reasonably) constant potential reference against which other potentials can be measured. An electrical ground system should have an appropriate current-carrying capability to serve as an adequate zero-voltage reference level. In*electronic circuit*theory, a "ground" is usually idealized as an infinite*source or sink*for charge, which can absorb an unlimited amount of current without changing its potential. Where a real ground connection has a significant resistance, the approximation of zero potential is no longer valid.*Stray voltages*or*earth potential rise*effects will occur, which may create noise in signals or if large enough will produce an electric shock hazard.
The use of the term ground (or earth) is so common in electrical and electronics applications that circuits in*portable electronic devices*such as*cell phones*and*media players*as well as circuits in*vehicles*may be spoken of as having a "ground" connection without any actual connection to the Earth, despite "common" being a more appropriate term for such a connection. This is usually a large conductor attached to one side of the*power supply*(such as the "ground plane" on a*printed circuit board) which serves as the common return path for current from many different components in the circuit.
Sent from my A574BL using Tapatalk
- Location
- New Jersey
- Occupation
- Journeyman Electrician
If I have a metal CT cabinet I cannot just bang two ground rods into the earth with a conductor to the rods and say that since it's connected to "ground" it's code compliant. The metal cabinet must be connected to the neutral not the "ground". The fact that engineers use the term ground in different ways is irrelevant. I don't know how that argument adds any value to the conversation it just makes the concept of connecting all metal parts on the line side of the service disconnect to the neutral more confusing.
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
Thank God the NEC definitions aren't written by those people, I suddenly have newfound respect for the CMPs that write the definitions we must abide by (and teach apprentices by.) That article couldn't have confused the issue any more if they tried. Posting that (complete with SWER) in a discussion about grounding and bonding electrical systems under 600V displays an utter lack of understanding of the topic at hand.
DrSparks
The Everlasting Know-it-all!
- Location
- Madison, WI, USA
- Occupation
- Master Electrician and General Contractor
K8MHZ
Senior Member
- Occupation
- Electrician
Big Wiki fail!!
DrSparks
The Everlasting Know-it-all!
- Location
- Madison, WI, USA
- Occupation
- Master Electrician and General Contractor
You keep saying that I am wrong and that this article is wrong but yet you offer no reasons why. My whole point is that many Professionals in the trade use the term ground to mean a common return path. I am well aware that electricity from a Transformer does not dissipate to the Earth but returns to the Transformer. If you don't understand this fact and then you don't belong in the trade. I think an apprentice would be more confused when after studying out of a book they get into the real world and someone mentions ground when they meant Bond
Sent from my A574BL using Tapatalk
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
This is an NEC forum. Use the terms from the NEC wrong and, well, you're wrong. Dropping anchor and insisting you're right simply makes you a fool, not right. The name of Part V of Article 250 is what? The name of 250.92 dictating the requirements is called what? Posting inaccurate Wikipedia articles (as pertaining to bonding of services) doesn't place you on high ground in this discussion.
DrSparks
The Everlasting Know-it-all!
- Location
- Madison, WI, USA
- Occupation
- Master Electrician and General Contractor
DrSparks
The Everlasting Know-it-all!
- Location
- Madison, WI, USA
- Occupation
- Master Electrician and General Contractor
Also the NEC refers to ground all the time. What about the term ground fault what do they call the green wire Inside the Box? I don't think the code is insinuating that these are literally connected to Earth ground
Sent from my A574BL using Tapatalk
Sent from my A574BL using Tapatalk
- Location
- Windsor, CO NEC: 2017
- Occupation
- Service Manager
The way of a fool is right in his own eyes,
But a wise man is he who listens to counsel.
-Proverbs 12:15
K8MHZ
Senior Member
- Occupation
- Electrician
You are confusing the name of the conductor with the function of the conductor, and I blame the NEC for most of that.
The function of the conductor is to provide a low resistance path back to the source of the electricity so that enough current will be drawn to trip an over current protection device. This function does NOT depend on a connection to the earth to work properly in any way shape or form. I have complained about this discrepancy for years to no avail.
The earth does not provide a low enough impedance path for the purpose at less than 600 volts.
DrSparks
The Everlasting Know-it-all!
- Location
- Madison, WI, USA
- Occupation
- Master Electrician and General Contractor
I know all this. I'm not making any such claim. My whole point is everyone uses the term ground to mean different things, even the NEC itself
Sent from my A574BL using Tapatalk
Then why did you post a bunch of nonsense from wiki and state you thought it was the best explanation?
Roger
K8MHZ
Senior Member
- Occupation
- Electrician
That may be one reason why, in addition to schooling, registered work hours are required in an apprenticeship.
Actually, my apprenticeship training was very concise on what each conductor's purpose was for and also very candid about the use and what seems to be mis-use of the term ground.
I would like to also stress not to use Wiki as a basis for argument with professionals. Wiki is a great starting point, but has a reputation for stating myths as fact.
DrSparks
The Everlasting Know-it-all!
- Location
- Madison, WI, USA
- Occupation
- Master Electrician and General Contractor
Okay perhaps Wikipedia was a bad source. The reason why I chose that article is because the author mentions that the term ground is often used to mean many different things. I wasn't aware that the article was claiming that a ground wire needs a physical connection to Earth ground to facilitate the operation of an ocpd. I will be more careful about what I post from now on
Sent from my A574BL using Tapatalk
Sent from my A574BL using Tapatalk
K8MHZ
Senior Member
- Occupation
- Electrician
It was probably the best explanation of his confusion. I don't mean that disrespectfully. I remember being confused about this when it came up in the apprenticeship along with most of the class. There were many bright people in our class that would point out things like the use of 'ground' in 'ground fault' when the ground isn't even needed for the ground fault protection device to work.
For some reason, the NEC, and the trades, refuse to address the inconsistencies that occur from today's use of the term 'ground'. I wish I knew why.
- Status