[BAZINGA]

We are building a new house and want to future proof it, so I have asked the builder to install a 240V/50amp circuit to the garage. What's nice is the main panel will be located in the garage and the outlet will require about 20 feet of 6/3 Romex. They quoted me $250. But I have some decisions I need to make by Monday.

Some additional info, I currently own a 2017 Volt with a CC LCS-25 hardwired in my garage, but if the retirement gods are good to me I plan on trading the Volt for a CPO Model S.

Now my questions:

1. Should I have them install a NEMA 14-50 outlet or just a box to allow for a hardwire install?

2. If I opt for the NEMA 14-50 outlet where does it get located. The CC HCS-50P comes with a 12' pigtail with a plug. The total assembly is about 30" top to bottom. Allowing for enough space for the 25' cable to be draped over the unit I calculate the plug would have to be about 36" to 40" up off the garage floor. They say that's legal.

3. I can always forgo the NEMA outlet and just asked for a junction box for a hardwire installation which I believe the Tesla HPWC has as standard.

4. I currently own a CC LCS-25 hardwired model, could that be wired to the 50amp circuit and just protected with a 20amp breaker for the time being?

I'm leaning towards Opt 4 since I already on a Level II EVSE and having a junction box for a 50amp line makes upgrading super easy.

Thoughts/comments/suggestions.

Thanks in advance

 

[Steverino]

I prefer a plug to hard wired. Gives you flexibility to remove/replace the unit as needed. My Siemens went Red fault after 7 years. While I'm waiting for them to determine the cause, I unplugged it and plugged in the original 240V Voltec unit I had rebuilt using OpenEVSE. Hardwired would not have allowed this quick and easy action.

The location of my outlet was specified by the Siemens installation manual either behind the unit (a pain) or below it about 16" which is the length of the cord. Below was my choice. It's 28" off the floor.

As long as that 50A circuit has nothing else on it except the EVSE, yes, you can downsize the breaker. The 50A wire may be heavier gauge than needed, but that's not really an issue.

 

[BAZINGA]

You answered all my questions, in fact I just ordered a CC HCS-50P and will stop by my house today and mark where I want the NEMA 14-50 outlet (about 36" off the garage floor). I'm also asking that the breakers for the EVSE be located in the lower left hand corner of my panel somewhat isolated from the normal house breakers.

Appreciate the detailed response, it was immensely helpful. Cheers

 

[Whatstreet]

My HCS-50P is installed outside so the outlet is in a covered box. The plug wire must exit from the bottom of the outlet box so the HCS-50P had to be installed next to the outlet. The Plug wire is 12" and does reach but barely. If the outlet wasn't in a box it would be possible to place the HCS-50P above the outlet with the plug wire exiting up. I suppose you could do that in a garage.

I had two 50A circuits installed and plan to get another HCS-50 for the other circuit, but the next one will not have the plug. I can switch off the breaker and use a screw driver to disconnect it if necessary.

 

[FI Spyder]

You can plug in a smaller amperage device into a higher amperage circuit, you do it all the time every time you plug in a floor lamp into a 15 amp circuit. Even things like clothes dryers, ovens, dish washers can come with plugs although sometimes they are hard wired in (either/or). Hardwiring just removes one possible instance of resistance while hampering the ease of unplugging. Pros and Cons of a minor/seldom needed convenience. Requiring a 20 amp circuit breaker to protect the circuit in case a 16 amp EVSE blows/shorts out isn't going to necessarily trip the circuit breaker. It might but it might not as the EVSE can well burn out before the breaker switches off. In short there are pros and cons to hard wiring vs plugs, nothing of any real consequence. If you are using the plug method just be aware they (high amperage plugs) aren't really meant to be plugged in/unplugged with the frequency of your AC clock radio.

 

[Don M]

If you are going to be using an EVSE which is rated significantly smaller than the 50 amp outlet, you should downsize the breaker to match the requirement of the EVSE. Not doing so would not be legal, it could result in a fire and your homeowners insurance would not like it if a malfunction in the EVSE was proven to be what caused the fire

I'm using my wife's 240 volt, 40 amp outlet to charge the Volt with a 16 amp EVSE and since I could not downsize the breaker (it would no longer run her kiln) I installed a pair of 20 amp fuses in the pigtail I plug into that outlet which powers my EVSE

Don

 

[FI Spyder]

If you are going to be using an EVSE which is rated significantly smaller than the 50 amp outlet, you should downsize the breaker to match the requirement of the EVSE. Not doing so would not be legal, it could result in a fire and your homeowners insurance would not like it if a malfunction in the EVSE was proven to be what caused the fire

I'm using my wife's 240 volt, 40 amp outlet to charge the Volt with a 16 amp EVSE and since I could not downsize the breaker (it would no longer run her kiln) I installed a pair of 20 amp fuses in the pigtail I plug into that outlet which powers my EVSE

Don

Better unplug all your appliances then because as they use less than the 15 amp breaker they would be illegal and could burn your house down.

 

[CcoastVolt]

My HCS-50P is installed outside so the outlet is in a covered box. The plug wire must exit from the bottom of the outlet box so the HCS-50P had to be installed next to the outlet. The Plug wire is 12" and does reach but barely. If the outlet wasn't in a box it would be possible to place the HCS-50P above the outlet with the plug wire exiting up. I suppose you could do that in a garage.

I had two 50A circuits installed and plan to get another HCS-50 for the other circuit, but the next one will not have the plug. I can switch off the breaker and use a screw driver to disconnect it if necessary.

@Whatstreet, if I read you right, you have a plug-in EVSE on an outside weather proof/resistant box? I'm hoping to be able to use an LCS-20P or LCS-24P with an outside plug, but have the upside of a plug-in version that Steverino speaks of. Are there any Code considerations with that type of set up?

 

[Steverino]

Better unplug all your appliances then because as they use less than the 15 amp breaker they would be illegal and could burn your house down.

We are talking about right-sizing wiring and a breaker for a DEDICATED circuit that feeds an EVSE and nothing else. High, continuous draw for 4-5 hours or more.

Similar, but not the same as a 15A circuit that feeds multiple outlets and that many things (TV's, lights, stereo's, etc.) could be plugged into. In that case, the breaker is mostly there to trip when too many things are plugged in (hair dryer + microwave + floor heater) that in combination are pulling too much current through the wires potentially causing wire charring, shorts, fire.

The combination of all those appliances overtaxing the circuit would be similar to a malfunctioning EVSE drawing too much power from its circuit. Same result in either case, the breaker trips and prevents a hazardous situation form escalating.

 

[jcanoe]

I believe this has been previously discussed. The EVSE is fused so if there is an internal failure within the unit the fuse would open. The electrical code makes an accommodation for a plug-in EVSE. Using the Clippercreek series LCS-20 EVSE as an example, the installation manual specifies a 20 amp breaker for a hard-wire installation of the LCS-20 EVSE but specifies either a 30 amp breaker or a 50 amp breaker when the LCS-20P is configured with a 6-30 or 14-30 plug or when configured with a 6-50 or 14-50 plug, respectively. Surprisingly, CC does not offer the LCS-20P in a 6-20 plug configuration. If you use a 20 amp breaker with a 14-50R and LCS-20P with 14-50 plug it would work but it would not meet code. The breaker and the receptacle have to have the same amperage rating.

 

[Don M]

Better unplug all your appliances then because as they use less than the 15 amp breaker they would be illegal and could burn your house down.

Any appliance which comes with a 50 amp plug contains wiring in it rated for 50 amps, so if there is a short somewhere, that 50 amp breaker will trip before there is a fire within the appliance. Now, if you plug a 20 amp EVSE into that outlet which has 16 and 14 and 12 gauge wire in it and you have a short, you could very well start a fire within the EVSE

Even the lamp with the 40 watt bulb that you plug into your 15 amp household outlet has wire sized to be safe when powered by a 15 amp breaker. EVSE's rated for 20 amps do not have wire rated for 50 amps

Don

 

[FI Spyder]

Any appliance which comes with a 50 amp plug contains wiring in it rated for 50 amps, so if there is a short somewhere, that 50 amp breaker will trip before there is a fire within the appliance. Now, if you plug a 20 amp EVSE into that outlet which has 16 and 14 and 12 gauge wire in it and you have a short, you could very well start a fire within the EVSE

Even the lamp with the 40 watt bulb that you plug into your 15 amp household outlet has wire sized to be safe when powered by a 15 amp breaker. EVSE's rated for 20 amps do not have wire rated for 50 amps

Don

Except you have EVSE rated at 16 amps plugged into 20 amp circuits (or 12 amp EVSE's plugged into 20 amp circuits). The electrical standards now have gone from split receptacle 15 amp circuits for counter top outlets to 20 amp circuits that the old devices can still plug into. Assuming the EVSE shorts, it is going to burn out leaving an open circuit without burning up either through a fuse, fusable link or electronic component. If it doesn't it's not going to get an UL certification.

 

[Don M]

I would be very careful ignoring the NEC and depending on a UL sticker not to burn my house down. The made in China Duosida EVSE I use to charge the Volt (from the 40 amp outlet, with 20 amp fuses in the pigtail) doesn't have a UL sticker on it, neither does the Open EVSE I built myself that I use to charge our two iMiEV's - The Panasonic EVSE that came with them (120 volts @ 8 amps only) does have a UL sticker. Just for the heck of it, I checked the Kobalt lithium charger for the electric lawn mower I bought at Lowes . . . . no UL sticker on that either

It's best to follow the code and not depend on someone who designed and built the object you're plugging in to your outlet not to catch fire - Fuses and circuit brealers are there for good reasons and should be sized accordingly

Don

 

[BAZINGA]

FYI my project has been decided, romex 6/3 protected by a 50amp breaker powering a Clipper Creek HCS-50P which draws no more than 40amps.

And should I get a Tesla the gen II UMC only draws a max of 48amps.

So I'm legal and safe for either option.

 

[Whatstreet]

@Whatstreet, if I read you right, you have a plug-in EVSE on an outside weather proof/resistant box? I'm hoping to be able to use an LCS-20P or LCS-24P with an outside plug, but have the upside of a plug-in version that Steverino speaks of. Are there any Code considerations with that type of set up?

The outlet box was inspected by the city, we have building permits for the installation. The covered outlet box ix the same one that is used in RV parks and meets the city code requirements. You can use a plug but 12" cord isn't long enough when plugged into a covered junction box. I recommend buying a cord and attach it to the terminal block in the charger with a screw driver.

 

[FI Spyder]

I would be very careful ignoring the NEC and depending on a UL sticker not to burn my house down. The made in China Duosida EVSE I use to charge the Volt (from the 40 amp outlet, with 20 amp fuses in the pigtail) doesn't have a UL sticker on it, neither does the Open EVSE I built myself that I use to charge our two iMiEV's - The Panasonic EVSE that came with them (120 volts @ 8 amps only) does have a UL sticker. Just for the heck of it, I checked the Kobalt lithium charger for the electric lawn mower I bought at Lowes . . . . no UL sticker on that either

It's best to follow the code and not depend on someone who designed and built the object you're plugging in to your outlet not to catch fire - Fuses and circuit brealers are there for good reasons and should be sized accordingly

Don

You can always use a device that doesn't pull as much power from the line (everybody does it all the time), standard operating procedure , you just can't use a device that pulls more than 80% of the power (against electrical code). Using a non UL device can and probably will invalidate your fire insurance. Check it out.

 

[ItsNotAboutTheMoney]

FYI my project has been decided, romex 6/3 protected by a 50amp breaker powering a Clipper Creek HCS-50P which draws no more than 40amps.

And should I get a Tesla the gen II UMC only draws a max of 48amps.

So I'm legal and safe for either option.

Tesla Gen 2 UMC allows max of 32A.
HPWC allow up to 80A.
But:
Model 3 LR max 48A AC so would be able to draw 40A using the J1772 adapter that's supplied with their cars.
Model 3 MR and SR are max 32A AC.