electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
no the neutral would take it back to the transformer winding
3 phase 4 wire
- Thread starter mdecastro
- Start date
- Status
no the neutral would take it back to the transformer winding
MAC702
Senior Member
- Location
- Clark County, NV
It's a grounded conductor.
- Location
- Lockport, IL
- Occupation
- Retired Electrical Engineer
That does not mean that dirt is part of the current's path. It means that the center point of the 120/208Y transformer secondary is intentionally connected to dirt. There are a number of good reasons for doing this, but giving current a path to planet Earth is not one of them.
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
Which has nothing to do with current flow under normal conditions. Current would return to the tranny whether or not that conductor is grounded or not.
That establishes a reference. 250.4(A)(1).
MAC702
Senior Member
- Location
- Clark County, NV
And I didn't say it was. Ground is a potential point at the transformer. The grounded CONDUCTOR is the best way to get there. This wasn't a thread about grounded conductors, but about pole current, hence the lack of detail. But I should have known better.
No. The neutral is. Grounded or otherwise.
But, as I already posted, the OP's question has been answered. Succinctly I was told.
Now, can we leave it at that? We don't want to confuse the issue, do we?
MAC702
Senior Member
- Location
- Clark County, NV
Not all grounded conductors are neutrals. But we usually refer to them as such for convenience.
We are done. Move on.
jumper
Senior Member
- Location
- 3 Hr 2 Min from Winged Horses
Prolly best.
kwired
Electron manager
- Location
- NE Nebraska
Only if a grounding electrode is installed and a grounding electrode conductor ties it to that point at the transformer.
Art 100
MAC702
Senior Member
- Location
- Clark County, NV
Could a system without such have a neutral? I hadn't considered that.
kwired
Electron manager
- Location
- NE Nebraska
As a general rule NEC requires a system with a neutral conductor to be the conductor that gets grounded when the system is grounded.
Outside of such rules you can ground any point of the system that you wish, you just don't want to ground more then one point or you get objectionable current, solid bonding of two different points in a source leads to short circuit levels of current.
Connecting two different grounding electrodes to two different points will result in current flowing between those points also, but will be limited by impedance of the grounding electrode(s) to earth connection if not otherwise solidly bonded together.
ggunn
PE (Electrical), NABCEP certified
- Location
- Austin, TX, USA
- Occupation
- Consulting Electrical Engineer - Photovoltaic Systems
Theoretically, yes, of course. You could, for example, have a transformer with multiple hot conductors and a neutral on the secondary and not ground any of them and it would work just fine. It might not be safe or legal but it would work. The neutral in a split phase system is merely the midpoint between the two phase voltages; it doesn't need to be grounded to act as the neutral.
Grounding provides a voltage reference to ground but usually no current flows into (or out of) it.
kwired
Electron manager
- Location
- NE Nebraska
"Hot conductors" leads to some misunderstanding sometimes. What most people call "hot conductors" is generally referred to as "ungrounded" if using proper terminology.
Many get confused with corner grounded systems and don't understand that you can ground a "phase conductor" - as I said before you can only ground one point of the system, NEC typically wants it to be whatever point leaves you with lowest potential to other points of the system, which a true neutral is equal to all other points of the system and will be lowest potential
ggunn
PE (Electrical), NABCEP certified
- Location
- Austin, TX, USA
- Occupation
- Consulting Electrical Engineer - Photovoltaic Systems
I will only argue with your "lowest potential" term. A neutral will at any point in time have a potential which is lower than one phase conductor and equally higher than the other in a split phase system. Three phase gets a little more complicated.
kwired
Electron manager
- Location
- NE Nebraska
Which is why I said "true neutral".I will only argue with your "lowest potential" term. A neutral will at any point in time have a potential which is lower than one phase conductor and equally higher than the other in a split phase system. Three phase gets a little more complicated.
Neutral of a high leg delta isn't a true neutral to the entire system, and NEC never used to call this particular use a neutral until sometime in the last 10 -15 years.
ggunn
PE (Electrical), NABCEP certified
- Location
- Austin, TX, USA
- Occupation
- Consulting Electrical Engineer - Photovoltaic Systems
That's not what I was saying. In, for example, in a "normal" 1P3W service where the neutral is grounded, at any point of time other than a zero crossing, one phase is at a higher relative voltage (potential) than the neutral/ground and the other is at a lower (negative) voltage. The neutral does not have the lowest potential of all the conductors. If you were to say that a grounded neutral has the lowest absolute value voltage of all the conductors, I would agree with that.
kwired
Electron manager
- Location
- NE Nebraska
Fair enough, I guess that lowest absolute value voltage of all the conductors is what I was trying to say.
SceneryDriver
Senior Member
- Location
- NJ
- Occupation
- Electrical and Automation Designer
I can relate to that.
My 1st exam had questions concerning color of plug fuses and western union splices
I just had to do some Western Union splices on a control panel project last week. Granted, they were splices carrying 3.3VDC, on 24ga wire, but it' still a very valuable skill to have. A little solder, a little heatshrink, and you get just about the lowest-profile splice possible.
SceneryDriver
- Status