FAQ: Home Tesla charging infrastructure Q&A

[comegetme]

Thanks, FlasherZ!
I slightly misphrased my original question. I meant the maximum number of bends between pull points, not the minimum bending radius. I was told that while 360 degrees is the general maximum, for thicker conductors it's less, e.g. maximum two 90 degree elbows for #2. Can someone confirm this? What is the maximum number of bends for #6 wires?

 

[FlasherZ]

Thanks, FlasherZ!
I slightly misphrased my original question. I meant the maximum number of bends between pull points, not the minimum bending radius. I was told that while 360 degrees is the general maximum, for thicker conductors it's less, e.g. maximum two 90 degree elbows for #2. Can someone confirm this? What is the maximum number of bends for #6 wires?

No Code limit except the 360 degree number (352.26). Electricians may avoid a lot of bends because it's harder to pull through, but with the right traps and pull ropes you won't have a problem.

 

[vinnie97]

Newbie questions here (which may be answered elsewhere, so apologies in advance), but does HWPC require a NEMA 14-50 for installation, or are they two separate methods of charging (i.e. is having a NEMA 14-50 installed a wasted effort if you're planning on going the HWPC route)? What are the advantages of the HWPC in comparison to just the standard plug? Better power management, faster charging?

 

[TexasEV]

Newbie questions here (which may be answered elsewhere, so apologies in advance), but does HWPC require a NEMA 14-50 for installation, or are they two separate methods of charging (i.e. is having a NEMA 14-50 installed a wasted effort if you're planning on going the HWPC route)? What are the advantages of the HWPC in comparison to just the standard plug? Better power management, faster charging?

HPWC is hard wired. NEMA14-50 is an outlet the UMC plugs into. As for pros and cons, please do a search. Lots of threads on this.

 

[FlatSix911]

Newbie questions here (which may be answered elsewhere, so apologies in advance), but does HWPC require a NEMA 14-50 for installation, or are they two separate methods of charging (i.e. is having a NEMA 14-50 installed a wasted effort if you're planning on going the HWPC route)? What are the advantages of the HWPC in comparison to just the standard plug? Better power management, faster charging?

HPWC is hard wired. NEMA14-50 is an outlet the UMC plugs into. As for pros and cons, please do a search. Lots of threads on this.

Correct.
You can install both the NEMA 14-50 outlet and the HPWC for a small incremental cost.

 

[Cosmacelf]

Usually you would install either the 14-50 receptacle for use with the UMC, or the HPWC. As to which is better, well, the UMC is smaller, and the 14-50 receptacle could be used for an RV plug in (but not while the car is charging). The HPWC is more reliable, and provides a faster charge rate if you have a dual charger Model S or a regular Model X.

 

[vinnie97]

Thank you all. I'm hoping the Model 3 will use the same HPWC interface. Don't have an EV yet so maybe I'll just hold off on adding any electrical hardware...plenty of time before the release of the next model.

 

[vinnie97]

Would it be prudent to have an HWPC installed now in preparation for the Model 3 or is there a risk of obsolescence? I guess the safer (and more economical) path would be to just "settle" for a NEMA 14-50 now and worry about faster charging options when the Model 3 launch is nearer. I'm just wondering how likely it would be for battery tech developments between now and 2017 to result in changes in charging requirements/equipment.

 

[TexasEV]

Would it be prudent to have an HWPC installed now in preparation for the Model 3 or is there a risk of obsolescence? I guess the safer (and more economical) path would be to just "settle" for a NEMA 14-50 now and worry about faster charging options when the Model 3 launch is nearer. I'm just wondering how likely it would be for battery tech developments between now and 2017 to result in changes in charging requirements/equipment.

If you don't have an EV and you aren't buying one imminently and have the specs for it, I would wait to install anything. It you are doing a construction project and need to do something now, I would just have a conduit run from your electrical panel to an empty junction box in the garage wall. Then when you buy an EV the electrician can come back and install whatever circuit is needed. That's what my electrician did when we remodeled four years ago, and I'm glad for that advice. At that time I was considering a Leaf in the future and ended up buying a Model S!

 

[vinnie97]

I've actually got such a box installed from a previous house improvement (to provide power for a tankless electric water heater). Hopefully, it will have enough capacity remaining for an eventual EV. If not, I'll likely just tolerate slower charging.

 

[ohaq]

I already created a post and then remembered this, need input on my setup before i fail inspection

http://www.teslamotorsclub.com/show...-Tesla-Please-Inspect-before-inspection-fails

 

[FlasherZ]

I already created a post and then remembered this, need input on my setup before i fail inspection

http://www.teslamotorsclub.com/show...-Tesla-Please-Inspect-before-inspection-fails

I posted my response there.

 

[TampaRich]

Groves Electric in Tampa did this setup for me. NEMA 14-50 as a backup in case the HPWC ever fails on me. They did a nice job running the wires through my attic and down inside the block wall. Super clean install. Highly recommend these guys. Very reasonable price. Half of what Tesla recommended electricians wanted to charge.

 

[FlatSix911]

Price?

Groves Electric in Tampa did this setup for me. NEMA 14-50 as a backup in case the HPWC ever fails on me. They did a nice job running the wires through my attic and down inside the block wall. Super clean install. Highly recommend these guys. Very reasonable price. Half of what Tesla recommended electricians wanted to charge.

View attachment 99770

 

[mknox]

Groves Electric in Tampa did this setup for me. NEMA 14-50 as a backup in case the HPWC ever fails on me. They did a nice job running the wires through my attic and down inside the block wall. Super clean install. Highly recommend these guys. Very reasonable price. Half of what Tesla recommended electricians wanted to charge.

Curious to know if that is to code. I assume you are running a 50 amp circuit. What happens if someone tries to use the HPWC and the NEMA 14-50 at the same time?

 

[TampaRich]

Curious to know if that is to code. I assume you are running a 50 amp circuit. What happens if someone tries to use the HPWC and the NEMA 14-50 at the same time?

Yep, 50 AMP circuit. Can only use one or the other, but not both at the same time. $850 installed for a 60' run.

 

[mknox]

Yep, 50 AMP circuit. Can only use one or the other, but not both at the same time. $850 installed for a 60' run.

I get that in practical terms you could only use one or the other... I just wonder if it's to code to wire it up that way. Maybe it is, and I don't doubt you know how it works, but down the road, someone may decide it's okay to plug an RV into the 14-50 while a car is charging at the HPWC (for example).

 

[FlasherZ]

I get that in practical terms you could only use one or the other... I just wonder if it's to code to wire it up that way. Maybe it is, and I don't doubt you know how it works, but down the road, someone may decide it's okay to plug an RV into the 14-50 while a car is charging at the HPWC (for example).

It's legal based on the non-concurrent load rules. It will trip the circuit breaker. I would place a sign there, myself.

It's not legal to install the HPWC configured to anything more than 40/50A, though, or connect that receptacle to a circuit with > 50A rating. I say that because there have been some questions about running a 100A circuit to an HPWC and simply tapping the 100A conductors for the 50A receptacle.

 

[Cottonwood]

It's legal based on the non-concurrent load rules. It will trip the circuit breaker. I would place a sign there, myself.

It's not legal to install the HPWC configured to anything more than 40/50A, though, or connect that receptacle to a circuit with > 50A rating. I say that because there have been some questions about running a 100A circuit to an HPWC and simply tapping the 100A conductors for the 50A receptacle.

That is analogous to how I run my Boulder garage. I have a 200 Amp sub-panel in the garage dedicated to EV charging. It contains a 100 Amp circuit breaker feeding an 80 Amp HPWC, a 90 Amp circuit breaker feeding a 70 Amp Roadster HPC, and a 50 Amp circuit breaker feeding a 14-50. There is no way that I could run all three at once, but the 14-50 is there only for testing and backup/occasional use, and the HPWC and HPC are there for regular use. I therefore meet the non-concurrent load rules.

Of course, I could not resist a test, and once plugged in three Teslas with currents adding up to 160 Amps to test the sub-panel. All worked well, but the sub panel did have a nice 60 Hz buzz going...

 

[FlasherZ]

Of course, I could not resist a test, and once plugged in three Teslas with currents adding up to 160 Amps to test the sub-panel. All worked well, but the sub panel did have a nice 60 Hz buzz going...

In the cool weather, you can hear my conduit buzzing rather loudly at 60 Hz for the first 3 minutes, until the conductors warm up a bit.