240V outlet wiring - Standard Color code for L1, L2 Pins X, Y

[dave6288]

Is there a standard color code for the X & Y pins on a 240V connector?

Where is the color code Specified?

Where are the X & Y pins specified?

I am interested in NEMA 14-50 10-30 6-20, L6-20, L6-30 6-50

I see it wired both ways on the internet.

It makes a difference on Electric Vehicle Chargers when you create a 120V adapter. L2 is specified as neutral

 

[Little Bill]

Is there a standard color code for the X & Y pins on a 240V connector?

Where is the color code Specified?

Where are the X & Y pins specified?

I am interested in NEMA 14-50 10-30 6-20, L6-20, L6-30 6-50

I see it wired both ways on the internet.

It makes a difference on Electric Vehicle Chargers when you create a 120V adapter. L2 is specified as neutral

What do you mean by color code?
On the 14-50, If you're using 240V, the X & Y are the hot terminals and it doesn't matter which 120V line runs to either one. The W is used for neutral.

10-30 X or Y could be used for hot and the other for neutral, W would be ground

6-20 no X Y markings

L6-20 is 240/250V only, doesn't matter which line wire goes to X or Y

L6-30 same as above

6-50 no X Y designation

 

[ActionDave]

There is nothing other the standard colour code in the NEC that white and green are reserved for grounded and grounding conductors.

I think the reason you are seeing L2 for neutral is convention, we've always labeled things L1 and neutral, or L1 and L2. No one ever labels anything L2 and neutral.

 

[mbrooke]

There is nothing other the standard colour code in the NEC that white and green are reserved for grounded and grounding conductors.

I think the reason you are seeing L2 for neutral is convention, we've always labeled things L1 and neutral, or L1 and L2. No one ever labels anything L2 and neutral.

Don't forget isolated power supplies- but chances are the OP is not dealing with that.

 

[ActionDave]

Don't forget isolated power supplies- but chances are the OP is not dealing with that.

Ya think? He's asking about a car charger.

 

[infinity]

10-30 X or Y could be used for hot and the other for neutral, W would be ground

Funny that this use W for the EGC and in other configuration the W is the neutral. Also for 120 volts shouldn't the neutral always be landed on the same letter when you have X and Y?

 

[mbrooke]

Ya think? He's asking about a car charger.

:lol::ashamed1::ashamed1: Lesson learned, I will not speed read posts! :happyyes:

 

[kwired]

Funny that this use W for the EGC and in other configuration the W is the neutral. Also for 120 volts shouldn't the neutral always be landed on the same letter when you have X and Y?

10-30 is 125/250 volt non grounding configuration - three wire dryer receptacle, when used as intended the W is a neutral conductor for an appliance that is allowed to have it's frame bonded to the neutral, the W terminal is not bonded to the device yoke though.

 

[Little Bill]

Funny that this use W for the EGC and in other configuration the W is the neutral. Also for 120 volts shouldn't the neutral always be landed on the same letter when you have X and Y?

I didn't state it should because the OP asked if there was a standard or requirement. But I would think that one or the other would be used consistently. If I'm not mistaken, I've seen and used the Y as the neutral for those that are combo 125/250V.

Now you may ask "Y" not the "X" for neutral!

 

[infinity]

10-30 is 125/250 volt non grounding configuration - three wire dryer receptacle, when used as intended the W is a neutral conductor for an appliance that is allowed to have it's frame bonded to the neutral, the W terminal is not bonded to the device yoke though.

Ah that make sense, there is no EGC with that configuration. I don't think that I have ever installed one of those.

 

[kwired]

Ah that make sense, there is no EGC with that configuration. I don't think that I have ever installed one of those.

My best recollection is most of those only have the neutral terminal identified with W, the other two don't matter and usually are not even marked with anything.

Add: if using it for it's intended purpose.

 

[dave6288]

Electric Vehicle Charger (EVSE) - Adapter wiring 120/240 Volt L2 is Neutral

Electric Vehicle Charger (EVSE) - Adapter wiring 120/240 Volt L2 is Neutral

How does this look?

The EV charger also called Electric Vehicle Service Equipment (EVSE) J1772 connector spec states that L2 is Neutral when operating on 120V. This creates a problem when using a 120V adapter if the 240V connector is not wired consistently. We typically use 6-20, L6-20, 6-50, 10-30 and 14-50 plugs and receptacles. Also need a consistent x & Y designation

below is the convention that I am using to manufacture adapters but I want to make sure that it is correct.

120 V Connector​	240 V Connector - 4 pin​	240 V Connector - 3 pin​
Hot​	Black​	Hot L1​	X​	Black​	Hot L1​	X​	Black​
Neutral​	White​	Hot L2​	Y​	Red​	Hot L2​	Y​	Red​
		Neutral​	W​	White​
Ground​	Green​	Ground​	G​	Green​	Ground​	G​	Green​

I didn't state it should because the OP asked if there was a standard or requirement. But I would think that one or the other would be used consistently. If I'm not mistaken, I've seen and used the Y as the neutral for those that are combo 125/250V.

Now you may ask "Y" not the "X" for neutral!

 

[MAC702]

Since pins 1 and 2 will both be 120V-to-ground when 240V to each other, I doubt that the device cares which one is 0V when the other is still 120V. This would be normal on welding machines (my world) that can operate on 120V or 240V input power. L2 is probably just spec'd as available to be N just to avoid describing all that.

That said, I don't see why a 120V adapter to the EVSE would have trouble keeping a neutral conductor on pin 2, unless someone broke the ground and plugged it in upside-down, something that can be done with many 120V devices that are abused.

Your chart looks correct, and the neutral wire would not even need to exist in the 4-prong adapter from NEMA 14-30 or NEMA 14-50 devices. You can still make that adapter with a 3-wire cord. You can even assemble the plug without that prong in many cases, which also makes it easier to insert and remove. We do it all the time in the welding machine world.

 

[jaggedben]

How does this look?

Below is the convention that I am using to manufacture adapters but I want to make sure that it is correct.

120 V Connector ​	240 V Connector - 4 pin​	240 V Connector - 3 pin​
Hot​	Black ​	Hot L1​	X​	Black​	Hot L1​	X​	Black​
Neutral​	White ​	Hot L2​	Y​	Red​	Hot L2​	Y​	Red​
		Neutral​	W​	White ​
Ground​	Green​	Ground​	G​	Green​	Ground​	G​	Green ​

]

Maybe this...

120 V Connector ​	240 V Connector - 4 pin​	240 V Connector - 3 pin ​
Hot​	Black ​	Hot L1​	X​	Black​	Don't ​	do ​	it. ​
Neutral​	White ​	Hot L2​	Y​	Red​	Don't ​	do ​	it. ​
		Neutral​	W​	White ​
Ground​	Green​	Ground​	G​	Green​	Don't ​	do ​	it. ​

Can you explain the purpose of these adapters you're making? Why would someone want to charge at 120V when 240 is available?

 

[jaggedben]

...
This creates a problem when using a 120V adapter if the 240V connector is not wired consistently.
...

It shouldn't. If you're using one hot and one neutral, it doesn't matter if the hot is black or red, just that it's a hot.

What does create a problem is if you want 120V and you don't have a neutral to work with.

 

[dave6288]

EVSE Electric Car Charger 240V - L1 L2 and Neutral - Adapter problem

EVSE Electric Car Charger 240V - L1 L2 and Neutral - Adapter problem

Here is the problem with the 120V Neutral and EVSE adapter.

For a given EVSE the wired relationship between L1/L2 at the (J1772) car plug end and X & Y at the 240V connector end is already established.

If you custom make an adapter you can make L2 at the J1772 the Neutral on the 120V plug

But if you want a general purpose adapter then the EVSE must be wired the same all the time. ie Y always goes to L2 on the J1772

Is there any standard that specifies the Wire Color for X & Y on a 14-50 range plug? (I have one that Black is on Y)

 

[MAC702]

...Is there any standard that specifies the Wire Color for X & Y on a 14-50 range plug? (I have one that Black is on Y)

No. While it is just very common that we will grab Black for X, there is no need to do so. Electrically, though maybe poor practice, you could reverse it at the other end of the cord, and it would make no difference.

 

[MAC702]

...Why would someone want to charge at 120V when 240 is available?

I'm guessing those specific ones are for those who may not have 240V available without adding a new circuit from the panel. That's common around here for homes built with gas service.

 

[jaggedben]

Here is the problem with the 120V Neutral and EVSE adapter.

For a given EVSE the wired relationship between L1/L2 at the (J1772) car plug end and X & Y at the 240V connector end is already established.

If you custom make an adapter you can make L2 at the J1772 the Neutral on the 120V plug

But if you want a general purpose adapter then the EVSE must be wired the same all the time. ie Y always goes to L2 on the J1772

Is there any standard that specifies the Wire Color for X & Y on a 14-50 range plug? (I have one that Black is on Y)

I still don't get what you are adapting to what. I think it would help to explain. Tell us exactly what can't plug into what without an adapter.

I ask because I think you're either worrying about a problem that doesn't exist or else doing something that no one should be doing.

 

[SceneryDriver]

How does this look?

The EV charger also called Electric Vehicle Service Equipment (EVSE) J1772 connector spec states that L2 is Neutral when operating on 120V. This creates a problem when using a 120V adapter if the 240V connector is not wired consistently. We typically use 6-20, L6-20, 6-50, 10-30 and 14-50 plugs and receptacles. Also need a consistent x & Y designation

below is the convention that I am using to manufacture adapters but I want to make sure that it is correct.

120 V Connector​	240 V Connector - 4 pin​	240 V Connector - 3 pin​
Hot​	Black​	Hot L1​	X​	Black​	Hot L1​	X​	Black​
Neutral​	White​	Hot L2​	Y​	Red​	Hot L2​	Y​	Red​
		Neutral​	W​	White​
Ground​	Green​	Ground​	G​	Green​	Ground​	G​	Green​

The charger is looking for a potential difference, nothing more. It actually shouldn't care which line is the neutral; the power supply is auto-ranging, like your laptop's power supply. You can plug it into 120V or 240V, and either pin can be the neutral.

Have a look at the connector standard:
https://en.wikipedia.org/wiki/SAE_J1772

SceneryDriver