I think you misunderstand his post ... he's ranting against those who describe the electrical requirements with a reference to "100 amp wire". So you're actually in agreement with him.
Charger FAQ/Explanation
- Thread starter hydbob
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My bad, then. Safety and enjoyment are what counts!
Hi Hydbob - Point #4 - regarding the scheduled charging. We hardwired the installation of our ChargePoint HomeFlex so that we can benefit from the discount plan from our utility company and setup the time to start charging the car. With the charging plug in the Lucid GT, we have the Chargepoint app scheduled to start at a particular time. Until it is time to start, we are getting an error message from our Lucid app. We have not been able to get the charging to start at the designated time and have to manually get the charging to start. Do you know if the current Lucid software system does not allow to schedule a start charging time or are we missing something in our set up?
Thank you for all that you do in this community. Thanks.
Current software does not.
Also, the scheduled charging via your EVSE was working with no error prior the the last few updates. It's a known bug and right now for Chargepoint, you will need to wale the car up at scheduled time or unplug and plug back in during your optimal TOU rates. Annoying. Yes. But it's a known bug that Lucid is working to fix.
Inadequate regression testing after software modification. Should be able to quickly fix this software bug introduced by another software mod.
It's a complete rewrite, so not quite the same
They probably weighed the pros and cons, and all of the faster features and everything loading up faster, faster responsiveness, was probably an accepted risk that moved onto production and they figured they'll fix the other stuff later/or a feature that just isn't implemented in 2.0.x
I agree with you, it wasn't quite end to end testing, but if it truly is a rewrite, then they don't have much to reference except comparing a list of features
Thank you. Now we wait, it would be nice to have that feature soon.
Thank you. That's what we've been doing, waking up the car and/or manually plugging it in.
Well I did hire a professional of some (local) repute, and told him I had ordered an 80 amp EV charger ( Lucid Connected Home Charging Station) that required an 100 amp hardwire line. I also told him I wanted to "future proof" the garage because the charger was bi-directional. He'd never heard of Lucid but I saw him look it up on the website. It cost me over $5000. I had the installation inspected by the municipality's hired gun and he approved the work.
I just went to check and see what he put in. 4 AWG.
This is why I should never trust a pro. This is why I usually do things myself.
Now what...
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Ask warrantee redo. #4, and 75 deg breaker (likely what you have) has ampacity 85 A. Next size breaker is allowed by code. This size is 90 A. If he set up the charger at 80 A, and your breaker is a 80 % breaker (very likely what you have), 125 % amp breaker is needed. This is 100 A breaker. The installation is an NEC violation. You could call the city inspector for your permit to verify all facts are ok.
Ouch! Now I feel doubly bad. Can you ask the inspector on what basis did he/she accept #4AWG on a 100-amp circuit?
Again, the "hired gun" township inspector barely looked behind the sub- panel. When he confirmed who did the work he pretty much signed the forms and gave me a sticker. Never looked at the main panel or the cable spec. to the garage sub-panel. The work order states "install 100 amp copper line to garage" but does not itemize or state the cable size/rating. I deliberately did not hover around or ask questions while the electrician worked. I did not think it would be necessary to explain how a car charger works, and I thought "100 amp cable to support 80 amps continuous 30 meters away" was enough clarity for a lay person talking to a professional. I was not aware that there are (at least) 4 cable sizes that are considered "100 amp", so I did not see my error in not itemizing and specifying what cable I wanted. I thought that was the reason you hired a pro. I was wrong, and I did not know that the inspector just approves any work done by an established company without even looking.
Check out this chart and see if 4 AWG is rated at 100 amps:
Table 1: American Wire Gauge (AWG) Cable / Conductor Sizes and Properties
cable size guideThis is what the inspector did not look at...he never asked to see the basement or the wiring.
I too thought everything was OK until I came back to post here and read what you folk are doing. Thanks guys. Please keep posting even if it seems obvious to you. Lots of lurkers.
I guess I could set the DIP switches inside the Lucid charger to lower the amps to 60, but I bought the Lucid charger to use ALL of it; both ways . Does anyone have a clue what the safe current is for this set-up ?
Here is from where I got my mis-information: (Lucid Insider) : prepare for your LCHCS
"Then Lucid send these details around how to get ready for the home charger unit:
“In order to future-proof your setup, please have your electrician follow the steps below,” Lucid said:
- you will want to hardwire the future wall charger to a breaker with at least 100-amp capacity (you will be drawing up to 80-amps from this setup)
- If you don’t have the capacity on your breaker, your electrician may want to proactively upsize this.
- You will want to run upsized wiring from the breaker to a junction box that’s in the area where you want to hang the future wall charger. This wiring should be rated for up to 100-amps.
- You will want to put a junction box in the area where you plan to hang the wall charger and have the upsized wiring lead to it.
- You will want to have the electrician hardwire the NEMA 14-50 outlet to the junction box and install an appropriately sized fuse.
- Once the wall charger is available, the electrician would only have to remove the junction box and NEMA outlet and hardwire the wall charger in its place. They will need to swap out the fuse to one that can accommodate up to 80-amps."
Nice to find there are many sloppy ways to avoid using the proper terminology. You can use "amps" or "temperature" or just say, "hire an electrician" and blindly trust them to pick the correct wire. Nobody will check. Or, if you want to be safe, do your own research and post here for confirmation. The more I look the worse it gets. I thought I'd be good lowering the DIP switches, but according to the chart below I'd have to lower the amperage to fourth level down from max.
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This may vary by location, but where I live, exposed wiring must be in conduit of one type or another.
Your contractor installed #4 Romex which is equivalent to NM-B, rated at 70A. Now, you have to downgrade that by 20% which leaves you at 56 amps. Find the setting that is the closest LOWER number on the Lucid charger. You're not done yet. The #4 Romex wired to a 100A breaker violates the electrical code. You need to replace that with a 70A (or lower number) breaker to meet code.
If your space is still exposed and you want maximum juice from your Lucid charger, you need to replace the #4 Romex with #3 THW or equivalent. I believe they need to be in conduit but not sure, probably depends on your local power company or codes. The ground wire can be a smaller size. The #3 will handle 100A and exactly matches your 100A breaker. That will provide 80 amps to your Lucid charger.
I think I have this right, but others please chime in.
I reread your message and your intent is to have two-way power sharing from your Lucid charger. If so, you will have additional hardware (and expense) such as an isolation (transfer switch), along with associated wiring. Those on the forum with Tesla wall chargers can give you the details. More wiring to come if that's your plan, but the wiring from/to the Lucid charger and isolation switch should be short. If you plan on a battery power wall, more wiring but should be internal between the switch and the power wall.
You weren't wrong at all. When a non-electrical person says 100 A wire, he/she means the load needs 100 A CB -- a 100 A circuit. (There's no such thing as a xxx A wire but dependent on the wire and its installation conditions and NEC.) The electrician is then to verify load nameplate -- Full Load Amperes. Let's say it says 80 A. The electrician is now to determine whether it's continuous (more than 3 hours) or non-continuous load. Since the charging will frequently take more than 3 hours, it's continuous load. Now, due to continuous and by NEC, you must do 80 A x 125 % = 100 A circuit. The CB and cable (and whatever else you have) must have 100 A rating.
The cable in your photo is NM-B. It's rated to 90°C (before insulation gets damaged). Per NEC, such a cable has 95 A ampacity. Per NEC you may use next size up CB, which is 100 A, given the CB is rated for 90°C. The CB in your photo is only rated for 75°C (and by far the most typical; 90°C CBs are very unusual). Thus, you need to use the lowest rating of the cable and CB. And this is 75°C. Your cable and for 75°C has ampacity 85 A. Next size up CB is allowed. This is 90 A. Thus, your installation is a NEC violation. The aforementioned is based on cable ambient max 30°. For higher ambient derating applies. For example, if you expect 108°F (for example, at the ceiling in the summer), the derating is 0.87 x 95 A = 83 A. Thus, max 90 A CB is allowed. One day per year heat 30°+C wave wouldn't necessitate derating; however, a few weeks per year of 30°+C would. The language is: likely, frequently, decently long continuous duration, etc. to occur.
Since a charger may draw the 80 A for hours at end, the next size up CB is not a good practice albeit allowed by NEC due to thermal heat buildup that may affect lifetime. A good gauge for 80 A continuous load with 100 CB is #3 (given max 30°C ambient), which is less commonly available, and next size #2 is often used instead. As an extra plus, #2 is now also rated for 108°C ambient.
To be NEC compliant for your present installation, you'd need to replace the CB to 90 A (given max 30°C ambient) and set the dip switches to 72 A or less. As not to use the next size up CB, I'd replace the CB to 80 A (given max 30°C ambient) and the dip switch to 64 A or less -- I'd do this if it were my house. This way you'd not promote long term meltdown at the lugs of the CB or charger or for the very worst causing a fire.
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Your electrician should have gotten this right. I would force him to come back out and fix it.
You could be right, but I assumed 90°C. Yes, for 60 °C that column needs to be used in the screenshot. I just looked up a typical NM-B up online and got 90°C. Cable part # and then data sheet would be needed to be absolutely sure or if printed on cable. I believe it used to be 60°C for (older) NM-B. See screenshot for Ampacity for redlined AWGs and temps and copper cable. Ampacity isn't to be confused with circuit ampere or CB ampere rating. Ampacity (for non-electrical people) can be viewed as maximum current the cable can carry under "ideal" installation conditions. Ampacity gives a hint of "maximum possible". Typical Ampacity deratings are ambient temp (above 30°C), number of current carrying wires in cable/conduit/raceway, installation on top of roof in direct sunlight, etc. Voltage drop for long runs is another consideration but typically not needed for 240 V and within a normal house size.
For a continuous load such as a charger, the CB need to be at least 125 % ampere larger than the Full Load Amperes as per charger nameplate. And now (a derated) Ampacity needs to be matched (exceed) that of the CB rating." Also, CB temp rating needs to be considered as per my previous post.
