ABYC E-8.17.4 (L2 conductor label)

[smac999]

the only place you would see L2 and neutral marked together is on a dual 30a 120v boat.

it would have an L1 hot and L1 neutral wire. and an L2 hot and L2 neutral entering the boat. with 2 separate double pole main breakers and 2 seperate neutral buses. and the buses would need to be designated as to which hot pairing they belong too.

on a 240v both you'd simply have L1 (hot), L2 (hot), and neutral.

most panels and volt gauges are marked as such. IE many 240v gauges on boat panels alow you to see L1 voltage, L2 voltage, and L1-L2 voltage. which would be 120v,120v, 240v

[Dockhead]

For whatever (little) it may be worth -- in the U.K., "L" wires must NOT be grounded. "L" means "Live" and it's the OPPOSITE of grounded.

The conductors of single phase AC power are designated L, N, and PE for Live, Neutral, and Protective Earth. "L" is live, and "N" is grounded.

The conductors of three phase AC power are designated L1, L2, L3, N and PE. Three live conductors and one grounded one, plus the protective earth wire.

Can you call a Neutral in a single phase system "L2" in North America? I don't know. I'm sure not going to argue with Rod about it -- I will immediately hear how ignorant I am, and I know that already without his telling me. But I do know something about the UK standards (which follow IEC 60364), and you sure as heck cannot call them that in the UK -- over here, "L" is Live, and Live is Live, and a Grounded conductor cannot be called "L" anything. Over here, Live and Grounded are opposites. North America might have its own different reality, where logic is less important, but I wouldn't know about it, and wouldn't venture an opinion.


As to L1 and L2 referring to the two split phases of a NA split phase system, as described by smac999, so that each one has its own "hot" (i.e. "live") and neutral -- that also seems to me like an abuse of the letter "L", but at least there is some necessity for it.

[DotDun]

Originally Posted by smac999

the only place you would see L2 and neutral marked together is on a dual 30a 120v boat.

it would have an L1 hot and L1 neutral wire. and an L2 hot and L2 neutral entering the boat. with 2 separate double pole main breakers and 2 seperate neutral buses. and the buses would need to be designated as to which hot pairing they belong too.

on a 240v both you'd simply have L1 (hot), L2 (hot), and neutral.

most panels and volt gauges are marked as such. IE many 240v gauges on boat panels alow you to see L1 voltage, L2 voltage, and L1-L2 voltage. which would be 120v,120v, 240v

Why label (2) 30A shorepowers as L1 and L2? Is that an ABYC standard? Why not SP1 and SP2?

[ramblinrod]

Originally Posted by evm1024

Actually this thread is about ABYC E-8.17.4 and the labeling of the neutral conductor L2.

This thread is not about any specific individual.

Post 11 makes it personal, and about a specific individual (moi).

It is a follow on to the other thread that got closed with this stated reason:

Too many people have neglected the "be respectful and be nice" parts of the community rules. Thread closed.

As I said.

That you self-identified as the Tech is your call.

I was the only one identified in that thread as ABYC certified, so it was poorly veiled ambiguity.

[john61ct]

I did not realize you had revealed your offline IRL identity, must have missed that thread.

I apologize for expressing my skepticism about your certification, and belatedly congratulate you on that achievement.

[DotDun]

Originally Posted by evm1024

I think that this is definitive....

E-8.17.4 Power wiring for receptacles shall be connected so that
the grounded (white) conductor attaches to the terminal identified
by the word "white" or a light color (normally white or silver).
The ungrounded conductor(s) shall be attached to the terminal(s)
identified by a dark color (normally brass or copper) and,
optionally, the letters X, Y, and Z or L1, L2, and L3.

Searching for a consensus on this topic from both SDOs and regulatory agencies. None of them support labeling the grounded conductor L2.

ABYC: L2 is ungrounded, attached to the dark color terminal

International Electrotechnical Commission (IEC), adopted by most of Europe: L2 is one phase of the 3, ungrounded, black (or brown)

UK AC power circuit wiring code: L2 is one phase of the 3, ungrounded, black (or yellow)

USA AC power circuit wiring code: L2 is one phase of the 3, ungrounded, red (or orange)

Canada AC power circuit wiring code: L2 is one phase of the 3, ungrounded, black (or red)

China AC power circuit wiring code: L2 is one phase of the 3, ungrounded, black (or yellow)

India AC power circuit wiring code: L2 is one phase of the 3, ungrounded, yellow

[evm1024]

I think that I may have come across one possible source of the confusion.

Words have meaning and power. At least in my experience if I understand a word incorrectly or use a word imprecisely then I get results at odds with the real world.

(step 1)

Lets take the quote below. At first reading we see what it means - there is a bundle of 3 wires to supply AC power. But the trap is that we have assigned an untruth to the white wire.

... reference to the 2 line voltage connectors to a 120 Vac GFCI, as “L1 (hot or black) and “L2 (neutral, white) ....

The untruth is that the white wire is at line voltage. The white wire is grounded and is thus at 0 volts in reference to the ground.

In everyday conversation we would not even think about it and in fact I did not think about it even after the 6 th reading but then it jumped out at me as I was trying to understand why you might label that conductor L2.

(Step 2)

In the first image we see a pretty hefty motor and a diagram of how to wire it up. On first look you see that the AC white wire is labeled L2 Hot or White Neutral. Many people especially if they are not thinking critically will equate L2 with Neutral. But of course that is not what this diagram says.

It says that this wire may be connected to L2 hot or White neutral.

It also says that this motor may be a 120 volt motor or a 240 volt one. It does not indicate L1 and we are likely to assume that L1 connects to the speed selection terminals.

The major point being that this diagram is an abstraction and is not definitive. L2 does not equal neutral. But if I were not thinking critically I just might make is so in my reading.

(step 3)

In the last image we see another motor and it appears that the black (ungrounded) and white (grounded) AC supply conductors come up from the bottom.

These conductors then connect to the motor starter "device" with the black wire to terminal L1 and the white wire to terminal L2.

Ah, L1 is the ungrounded (hot) conductor and L2 is the grounded (neutral) conductor one might think. But the transference of the name of the connector to the name of the conductor is false.

Specifically the names of the line side terminals of a motor starting device are required to be named L1, L2, L3, L4 by code. One such code is NEMA standard ICS 2-321A.60 but that is neither here or there. The point is that the terminal names do not name the conductor.

(conclusion)

Frequently when reading I am not reading much deeper that a quick skim. I have far too often read thinks like "L2 hot or white neutral and left off the OR. And somewhere in the back of my mind I remember that L2 can be neutral. Do this often enough and I might just forget to think that L2 is not neutral.

Words have power, power to set how we think about things. On the street it is a stop light because it is there to tell us when to stop. On a drag strip it is not a stop light because it is there to tell us when to go. We look at those lights differently. If you go when a stop light just turns green you may be hit by someone who runs the light. At least a prudent driver does.

By the same token. The use of conductors labeled L1, L2, L3 as carriers of lethal voltages as the dominate use of that label preempts their use for neutral conductors. At least for the prudent.

[evm1024]

As a side note I've looked at at least 50 images and spec sheets for GFCI. I have found that none of them (zero, nada, zip) label their neutral terminals L2 either on the line or load side.

None of them.

[evm1024]

Originally Posted by smac999

the only place you would see L2 and neutral marked together is on a dual 30a 120v boat.

it would have an L1 hot and L1 neutral wire. and an L2 hot and L2 neutral entering the boat. with 2 separate double pole main breakers and 2 seperate neutral buses. and the buses would need to be designated as to which hot pairing they belong too.

on a 240v both you'd simply have L1 (hot), L2 (hot), and neutral.

most panels and volt gauges are marked as such. IE many 240v gauges on boat panels alow you to see L1 voltage, L2 voltage, and L1-L2 voltage. which would be 120v,120v, 240v

Many inverter/chargers have dual AC inputs and dual AC outputs.

The AC inputs are for L1 and L2 either in split phase or dual AC feeds (50 amp or two 30 amp feeds).

The AC outputs on the inverter/charger are labeled L1 and L2 at least in older models. And the key is that only one of the outputs is connected to the internal transfer switch (and thus can be powered by the inverter).

On boats that have a single 30 amp shore power feed it is not uncommon to wire the shore power to both the AC inputs to the inverter/charger.

The AC outputs from the inverter/charger are often labeled L1 and L2. On my boat the inverter/charger had the L2 circuit wired through the transfer switch and inverter supplied power.

The transfer switch fed AC wiring goes to anything that you want run from the inverter when there is not shore power and the other AC wiring goes to things you never want fed from the inverter, Space heaters, Air Conditioning units, hot water tanks (you pick).

I was somewhat confused by this when I first came across an L2 in a single shore fed boat. A bit of conversation with Xantrex support took care of that confusion.

[DotDun]

The nice things about standards, there are so many.

NEMA defines the standards for terminal markings on electric motors, they do not define distribution wiring standards.

https://law.resource.org/pub/us/cfr/....mg-1.2009.pdf

(see section 2.2 - page 86 in the pdf)

NEMA has their own set of requirements/reasons for terminal marking.

An engineer that understands both sides of that demarcation point (motor/distribution wiring) will clearly understand why the labels can't be shared across that demarcation.

But it is reasonable why/how a technician might get confused.

[evm1024]

Originally Posted by ramblinrod

SNIP


I then posted a link to a booklet of electrical wiring diagrams produced by Schneider Electric...

https://download.schneider-electric....Ref=0140CT9201

...that clearly illustrates the connections to a 120Vac single phase electrical power supply as "L1" and "L2" where it identifies that L1 is always the ungrounded conductor, so by inference for a supply with a ground conductor, it is connected to "L2" which may commonly be referred to as "neutral".

Conclusion 2: The other poster was "incorrect", in the declaration that "L2 is never white or neutral".

You then link to a book by Schneider that clearly shows wiring connections to Motor starting devices which as has been noted in this thread have nothing to do with the connector names. They are set by code.

Once again you claim that this book which has nothing at all to do with boats, GFCI, AC conductor naming conventions etc as proof of your position.

As has been said more than once in the past - saying it over and over does not make it true.

You know that this book does not apply and does not support your position.


Proper labeling of conductors will help prevent confusion and potential dangers. Ron surely you can see that we need to use proper names. A wrong name is a bit jarring.

[evm1024]

Hi All,

Rather than debating back and forth forever I sent an email off to ABYC. I asked them if under ABYC rules if it would be permissible to mark the neutral line L2 to which one of their Asst Directors of Education responded:

You would want to mark the neutral appropriately as neutral not L2.


Short, sweet and to the point. Marking a neutral "L2" is incorrect according to the ABYC.

[DotDun]

Originally Posted by evm1024

Hi All,

Rather than debating back and forth forever I sent an email off to ABYC. I asked them if under ABYC rules if it would be permissible to mark the neutral line L2 to which one of their Asst Directors of Education responded:

You would want to mark the neutral appropriately as neutral not L2.


Short, sweet and to the point. Marking a neutral "L2" is incorrect according to the ABYC.

That works for me....

[DotDun]

To summarize this debate.....

There are two standards development organizations (SDOs) that produce the majority of the guidelines for the world for AC electric wire distribution, NPFA (mostly North America) and IEC (mostly EU and Asia). Regulatory agencies take the output of these SDOs and codify them into regulation at the Country/State/Local levels. Some niche market segments like boats are covered by ABYC/others and may or may not be codified.

Electric motor standards are yet another organization, NEMA. Since these appliances have a different level of complexity, it's typical that a single organization (like NPFA and/or IEC) doesn't cover the complete spectrum, hence different organizations of like minded engineers are formed to define standards for the different disciplines. NEMA standards are codified by the USA at the Federal level (as referenced in an earlier post).

The example used earlier in this and the now closed thread was to extrapolate the terminal marking(s) from an electric motor and declare a label for the distribution wire feeding the motor. The example was that it's perfectly OK to label the neutral/grounded wiring conductor as 'L2' when it connects to the an electric motor terminal marked 'L2'. It's been shown in earlier posts that 'L2' has a completely different meaning in the wiring world and by 're'-labeling the wire using an electric motor terminal marking, it could confuse someone in the future and be a potentially dangerous situation.

Hopefully by explaining that these 2 sets of standards are derived from different organizations, and yes they may seem to disagree, you can now see they actually are not in conflict with each other. 'L2' simply has a different meaning for wire distribution than an electric motor terminal marked as 'L2'. There is a demarcation between the end of the wire and the terminal on the motor from a standard labeling perspective.

The correct statement is:

The neutral/grounded conductor from the AC electric wire distribution connects to the electric motor terminal marked L2.

The wire shall be labeled as 'N' as it is the neutral wire. The motor terminal is already marked 'L2'. A diagram showing wire 'N' connecting to motor terminal 'L2' is what should be documented/provided. I have witnessed tags on wires stating "connects to motor terminal L2", which seems to be OK, IMO.

[ramblinrod]

Originally Posted by evm1024

I think that I may have come across one possible source of the confusion.

Agreed, there appears to be some confusion...(it's just not on my part).

Originally Posted by evm1024

Lets take the quote below. At first reading we see what it means - there is a bundle of 3 wires to supply AC power.

Error 1: For a single phase AC electrical supply, there is not a bundle of 3 wires to supply AC power.

Tutorial 1:

A single phase AC power source typically has two terminals that "supply power".

If the connected AC electrical distribution system has a safety ground (a "grounding" wire per ABYC), under normal operation it does not carry current, therefore, it does not "supply power" to connected circuits.

Only two "wires" supply power in a single phase AC electrical distribution system.

Originally Posted by evm1024

The untruth is that the white wire is at line voltage.

Error 2: You have created the "untruth". I certainly have never claimed a "white wire is at line voltage".

Tutorial 2:

A single phase AC power source typically has two terminals that "supply power".

When these terminals are connected to an AC electrical distribution system, the two conductors may be referred to as "Line Voltage Conductors".

Scenario A) If the "Line Voltage Conductors" are floating, the 2 line voltage conductors are "at line voltage" with respect to one another.

Scenario B) If one of the two "Line Voltage Conductors" (typically "L2") is grounded, there is still "Line Voltage" between the 2 conductors.

The only difference is, one conductor (typically "L1") is at "Line Voltage Potential" with WRT (with respect to) ground, and the other conductor (typically "L2") is at 0 Vac (or near 0 Vac) WRT ground.

There is still "Line Voltage" between the 2 conductors, and the 2 conductors together are still commonly referred to as "Line Voltage Conductors". For differentiation purposes, one of the "Line Voltage Conductors" may be referred to as "Line", and the other "Line Voltage Conductor" may be referred to as "Neutral". (Neither of the 2 "Line Voltage Conductors" can conduct "Line Voltage" (under normal circumstances) without the other.)