Questions about setting up a wall connector

[Mooeymoose]

Can I ask a new question about Tesla charging. I just ordered the new Tesla Universal charger and I have become so confused about max amp draw for a setup and have seen mixed information.
This is what I have done.
A) Tesla hardwired wall charger has two hot wires (Red an black) and ground (green). White or neutral is not needed.

B) I spend a while setting up my detached garage running 11/4 rigid conduit underground (live in Chicago area) and at a junction box split to two 3/4 conduit to two separate sites in my garage to "future proof" my setup since I will only need one now.

C) I am using 6awg THHN / THWN-2 wire from a 60 am non-ground fault breaker going 120 feet without interruption directly to a wall charger. I installed 6 wires. Two red, two black and 2 green.

D) I read this from Tesla,

• For sites with multiple Wall Connectors, each Wall Connector must have its own branch circuit with L1,
  L2/N, and Ground.

E) I will be tightening the wires accounting to the torque requirements.


My questions are as follows.
1) what is L2/N. I are mostly confused about the /N. Do I need a neutral?
2) Being less than 150ft at 220V I believe the amp rating is unchanged but can my setup pull 48 amps continuous? I have seen so many different rating for Romex, THHN at 6awg that I am confused. 80% max limitation for continuous load but what is my max?
3) Any issue with putting two 60amp circuits on the same 200 amp Panel next to one another?
4) Should I have used 4awg to get the full 48 amps continuous? if so I would need to change the 3/4 conduit to 1 inch.

Help.

 

[jjrandorin]

There are people who are much more versed in this than I am, but I believe that 6AWG THHN is fine for 60 amp circuit / 48 amp charging. The 80% rule means you setup a 60 amp circuit for 48amp charging (and need to be buying a Long Range or Performance vehicle to get that 48amp charging since RWD only charges at 32amp max).

Your setting up one wall connector, right? If so, ignore instructions for more than one.

 

[Cosmacelf]

Can I ask a new question about Tesla charging. I just ordered the new Tesla Universal charger and I have become so confused about max amp draw for a setup and have seen mixed information.
This is what I have done.
A) Tesla hardwired wall charger has two hot wires (Red an black) and ground (green). White or neutral is not needed.

B) I spend a while setting up my detached garage running 11/4 rigid conduit underground (live in Chicago area) and at a junction box split to two 3/4 conduit to two separate sites in my garage to "future proof" my setup since I will only need one now.

C) I am using 6awg THHN / THWN-2 wire from a 60 am non-ground fault breaker going 120 feet without interruption directly to a wall charger. I installed 6 wires. Two red, two black and 2 green.

D) I read this from Tesla,

• For sites with multiple Wall Connectors, each Wall Connector must have its own branch circuit with L1,
  L2/N, and Ground.

E) I will be tightening the wires accounting to the torque requirements.


My questions are as follows.
1) what is L2/N. I are mostly confused about the /N. Do I need a neutral?

Ignore the N. The two hots from the breaker go to L1 and L2 in the Wall Connector. you don’t use a neutral. The green wires are connected to ground.

2) Being less than 150ft at 220V I believe the amp rating is unchanged but can my setup pull 48 amps continuous? I have seen so many different rating for Romex, THHN at 6awg that I am confused. 80% max limitation for continuous load but what is my max?

You can charge at 48A.

3) Any issue with putting two 60amp circuits on the same 200 amp Panel next to one another?

No, that’s fine.

4) Should I have used 4awg to get the full 48 amps continuous? if so I would need to change the 3/4 conduit to 1 inch.

No.

 

[Mooeymoose]

There are people who are much more versed in this than I am, but I believe that 6AWG THHN is fine for 60 amp circuit / 48 amp charging. The 80% rule means you setup a 60 amp circuit for 48amp charging (and need to be buying a Long Range or Performance vehicle to get that 48amp charging since RWD only charges at 32amp max).

Your setting up one wall connector, right? If so, ignore instructions for more than one.

One setup to start but I want to wire it with six wires (2 sets of 3) incase in the future I had two electric cars. However, for now there is only going to be one charger connected.

 

[Mooeymoose]

Ignore the N. The two hots from the breaker go to L1 and L2 in the Wall Connector. you don’t use a neutral. The green wires are connected to ground.



You can charge at 48A.



No, that’s fine.

No.

Next time, please start a new thread, don’t hijack an existing one.

Thank you

 

[Rocky_H]

1) what is L2/N. I are mostly confused about the /N. Do I need a neutral?

There are two types of electrical systems in the U.S. For residential, that is split phase, and it has that usual Line1 and Line2, that have a 240V difference between them. That's what you would use, and neutral isn't needed. For commercial/industrial properties, they are frequently supplied from a 3 phase system, where a hot line to neutral is 208V, so that is why the wall connector says it might be Line1 and neutral for the two sides of the voltage connection.

2) Being less than 150ft at 220V I believe the amp rating is unchanged but can my setup pull 48 amps continuous? I have seen so many different rating for Romex, THHN at 6awg that I am confused. 80% max limitation for continuous load but what is my max?

For individual wires in conduit, like you are using, that is THHN, and 6 gauge of that does have a 65A rating, so a 60A circuit is allowed there, and it can draw 48A continuous.

3) Any issue with putting two 60amp circuits on the same 200 amp Panel next to one another?

Shouldn't be any problem.

One setup to start but I want to wire it with six wires (2 sets of 3) incase in the future I had two electric cars. However, for now there is only going to be one charger connected.

You're going to a detached garage. The simpler way that people usually do this (which I think is also cheaper on wire cost) is to run a single set of wires of thicker gauge to get that supply into a subpanel in the garage. The requirement of being two separate branch circuits doesn't mean they have to be separate homeruns ALL the way back to your main panel. You can just branch them from the subpanel in the garage.

 

[FireFighterHil]

Like Rocky_H says, I believe you would be much better served by running a 100amp sub panel to the garage and then branching off from it. This will also allow you to do things like install regular outlets, lighting, and in the future hook up another Wall connector.

 

[ATPMSD]

what is L2/N. I are mostly confused about the /N. Do I need a neutral?

Just to fully answer your question, the L2/N post serves one of two purposes:

In a 240V circuit, the L1 and L2/N and where you connect to the two “hot” wires

In a 120V circuit, which the connector supports, you connect the “hot” to L1 and the “neutral” to L2/N

 

[Mooeymoose]

Just to fully answer your question, the L2/N post serves one of two purposes:

In a 240V circuit, the L1 and L2/N and where you connect to the two “hot” wires

In a 120V circuit, which the connector supports, you connect the “hot” to L1 and the “neutral” to L2/N

Thank you for that missing link. I get it now.

 

[Mooeymoose]

Like Rocky_H says, I believe you would be much better served by running a 100amp sub panel to the garage and then branching off from it. This will also allow you to do things like install regular outlets, lighting, and in the future hook up another Wall connector.

I did not think of that but yes that would have been better. I guess with 11/4 I can always upgrade provided my pipe does not rust through. Since it is RMC it should last a little while.

 

[davewill]

You could also choose to replace your junction box with a small subpanel, and run two wall connectors off of the single 60a feed from the main panel using load sharing, if you don't want to pull new wires to the garage. In that case, one car plugged in would still get the full 48a, but two cars would split it.

 

[Mooeymoose]

There are two types of electrical systems in the U.S. For residential, that is split phase, and it has that usual Line1 and Line2, that have a 240V difference between them. That's what you would use, and neutral isn't needed. For commercial/industrial properties, they are frequently supplied from a 3 phase system, where a hot line to neutral is 208V, so that is why the wall connector says it might be Line1 and neutral for the two sides of the voltage connection.


For individual wires in conduit, like you are using, that is THHN, and 6 gauge of that does have a 65A rating, so a 60A circuit is allowed there, and it can draw 48A continuous.


Shouldn't be any problem.


You're going to a detached garage. The simpler way that people usually do this (which I think is also cheaper on wire cost) is to run a single set of wires of thicker gauge to get that supply into a subpanel in the garage. The requirement of being two separate branch circuits doesn't mean they have to be separate homeruns ALL the way back to your main panel. You can just branch them from the subpanel in the garage.

Yes, thinking about it now that does make more sense and is something I may change. I do have a grounding question if it do this. I understand the reason to only bond neutral and ground at the main panel but do I need to ground the sub panel locally since it’s in a different building or can I just run a ground back to my main panel? And I imagine the ground should be able to handle the full amp rating of the entire sub panel?

 

[dafish]

Ground back to the main panel.

The ground can be downsized one size as i recall.

 

[Rocky_H]

I understand the reason to only bond neutral and ground at the main panel but do I need to ground the sub panel locally since it’s in a different building or can I just run a ground back to my main panel?

That one is getting a bit out of areas I am familiar with, so I had to Google for it. Normally, within a house, any subpanels just have to continue the neutral and ground connections independently through them. But it looks like this is an additional condition for a separate detached building that it does also need its own separate ground rod. Here's a page from the Mike Holt forum about it:

Ground rods on sub panel detached garage

My inspector is telling me I'll need ground rods on a sub panel in a detached garage. I want to run a four wire feeder to the sub panel. 250.32(B)(1) states - "an equipment grounding conductor shall be run with the supply conductors and connected to the building or structure disconnecting means...

forums.mikeholt.com

And I imagine the ground should be able to handle the full amp rating of the entire sub panel?

Ground lines are done smaller.

The ground can be downsized one size as i recall.

It's more than just one step down. It has its own separate table in NEC.

For example, let's look at a 100A supply line to a garage:

Cerrowire Resources - Ampacity Charts

Ampacity is the maximum current that a conductor can carry continuously under the conditions of use without exceeding its temperature rating. Cerrowire's ampacity chart helps calculate the load requirement for a circuit.

www.cerrowire.com

From that table for hot conductors, THHN wire in conduit would need to be 3 gauge copper.
The ground size table is NEC 250.122

Size of Equipment Grounding Conductors | UpCodes

Explore a searchable database of US construction and building code. Code regulations are consolidated by state and city for easier navigation.

up.codes

It shows that for a 100A supply, the copper ground can be 8 gauge.

 

[davewill]

You could also choose to replace your junction box with a small subpanel, and run two wall connectors off of the single 60a feed from the main panel using load sharing, if you don't want to pull new wires to the garage. In that case, one car plugged in would still get the full 48a, but two cars would split it.

I just reread the first post and just realized he's already run two sets of 6ga THHN from the main panel to the garage, so no need for load sharing or a subpanel.

 

[gfunkdave]

There are two types of electrical systems in the U.S. For residential, that is split phase, and it has that usual Line1 and Line2, that have a 240V difference between them. That's what you would use, and neutral isn't needed. For commercial/industrial properties, they are frequently supplied from a 3 phase system, where a hot line to neutral is 208V, so that is why the wall connector says it might be Line1 and neutral for the two sides of the voltage connection.

Three phase wye systems are 120V line to neutral and 208V line to line. Unless it's a high leg delta system (uncommon) then there's one phase that's 208 line to ground, the other two are 120V to ground, and all phases are 240V phase to phase.

Just to fully answer your question, the L2/N post serves one of two purposes:

In a 240V circuit, the L1 and L2/N and where you connect to the two “hot” wires

In a 120V circuit, which the connector supports, you connect the “hot” to L1 and the “neutral” to L2/N

The wall connector's specified input voltage is 200-240V. It does not support 120V operation. The neutral marking is for systems with 200-240V line to neutral. I bet they just use the same plastic plate (with the same labels) in Europe, where that makes more sense.

 

[ATPMSD]

The wall connector's specified input voltage is 200-240V. It does not support 120V operation.

I stand corrected. Thank you.

 

[kimwin]

My Wall Connector is 2 feet below the main panel. Making installation simpler. Don't have to run long wires.
In your case, the idea for adding a subpanel seems to be the best as it gives you more flexibilities when adding more breahers and circuits as you need.

 

[Eric33432]

. . . . For commercial/industrial properties, they are frequently supplied from a 3 phase system, where a hot line to neutral is 208V, so that is why the wall connector says it might be Line1 and neutral for the two sides of the voltage connection. . . .

In the US, a 208 Y system is 208 volts line to line and 120 volts line to neutral, not 208 volts line to neutral.

 

[Rocky_H]

In the US, a 208 Y system is 208 volts line to line and 120 volts line to neutral, not 208 volts line to neutral.

There are a few different types and configurations of 3 phase systems, and yes, that is the most common.