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Your generator's transfer switch might have load shedding capability. Lots of the bigger ones do. When the load on the generator gets too big it drops a selected load, like water heater or AC or maybe even EVSE. Your electrician should be able to help you.
Generac load shedding is a joke. The only thing smart about their load shedding is that it cuts off the AirCon loads by interrupting the low voltage demand signal. If it detects an actual overload it cuts everything off, then starts again.
 
Short version: Is it legal to install an EVSE in a bedroom?

Long version: Not sure where to post this, but I have a question about possible workarounds for condo charging. All the condo charging threads focused on getting the HOA approval to install charge equipment or at least outlets in a shared garage. I've already been told I cannot make any permanent modifications to the exterior of the building or run conduit or do any trenching. The board was very clear on this, no exceptions. Plus there is no garage, just outdoor parking. The assigned covered spots (long open carport) are on the other side of the parking lot, away from the building. Spots against the building are unassigned but I can usually but not always get an open spot right outside my unit. The head of the HOA told me to "throw your cord out the window" so I did just that with my Leaf's trickle charger. I live on the 2nd floor, and my bedroom window is the only one that faces the parking lot (only other windows face the courtyard on the opposite side of the building). I don't know if it's technically legal but at least so far the HOA which is very picky about stuff hasn't said anything. I will need to charge at most twice a week so while inconvenient this is tolerable for me but when I get my ≡ I would like to charge at a faster rate. I have many questions about legality.

Is it legal to install an EVSE in a bedroom?

Also, is a 14-50 permitted or would it have to be hardwired? Just asking this because I want flexibility in my charging options for both EV's.

Finally, since I might not always have access to the closest parking spot, I was curious about charge cable extensions. The OP's FAQ's specifically said these are illegal, but there is a very reputable looking site that I suspect has ties to a TMC member that is selling J1772 extension cords. Are we sure it is forbidden or is it a legal gray area, a do-it-at-your-own-risk situation? Personally I think the risk is minimal if it conforms to the J1772 safety standards on both ends.
 
Short version: Is it legal to install an EVSE in a bedroom?

There are no restrictions on where the HPWC could be installed. The Code has a provision which states you can't run power cords through windows or doors, but it would be arguable as to whether it applies to the cord on the HPWC.

Also, is a 14-50 permitted or would it have to be hardwired? Just asking this because I want flexibility in my charging options for both EV's.

The FAQ covers this. Bottom line is that it's not illegal Code-wise, but Tesla has told me that it isn't intended for connecting with a plug. Some people have done it.

Finally, since I might not always have access to the closest parking spot, I was curious about charge cable extensions. The OP's FAQ's specifically said these are illegal, but there is a very reputable looking site that I suspect has ties to a TMC member that is selling J1772 extension cords. Are we sure it is forbidden or is it a legal gray area, a do-it-at-your-own-risk situation? Personally I think the risk is minimal if it conforms to the J1772 safety standards on both ends.

It is indeed illegal per the code. Tesla says in its instructions that extension cords are not to be used, and NEC 110.3 says you have to follow manufacturer's instructions.

If it's a J1772 extension cord, then it likely violates the 25 foot maximum length provision of article 625.

As to whether it's a safety violation? It's relatively safe if well-built. But there may be insurance and liability implications if it is involved in a fire. I know plenty of people who use them.

All code violations are performed at your own risk. Typically, each day you use it is a separate violation and is eligible for a fine. In some local codes, its a misdemeanor offense - beyond a citation. But will an inspector bust your door down and write you a ticket? It's unlikely unless you're doing this in a commercial environment where OSHA might come through.
 
@FlasherZ Thanks for your response. I think my best bet would be to go with a hard wired J1772 EVSE for now and then use an adapter for the Tesla. If in the future I get rid of the Leaf (gf was going to drive it but I think she already has range anxiety) and my panel is sized for it I could go with a higher powered Wall Charger. I just need to find an electrician who interprets the cord out the window thing as being legal and is comfortable doing it.
 
Had my 14-50 outlet installed today — by swapping out the previous L6-20 outlet — View attachment 164967


I don't understand what I see in your attached pic. You have what appears to be a POCO meter connected to the box that contains your 14-50 outlet, which is in turn connected to your panel. Of course, we can't see the wiring inside those conduits (that appear to be 1" EMT, so too small for main entrance), so the function is unclear. Are you metering the power going through the 14-50 for some reason?
 
I don't understand what I see in your attached pic. You have what appears to be a POCO meter connected to the box that contains your 14-50 outlet, which is in turn connected to your panel. Of course, we can't see the wiring inside those conduits (that appear to be 1" EMT, so too small for main entrance), so the function is unclear. Are you metering the power going through the 14-50 for some reason?
Yes, I have a meter to track my EV charging. You can buy a refurb utility meter from Hialeah Meter for relatively little. My power co-op has a net metering smart meter on my house, since I have solar panels. [I currently have a credit balance with them of 914 kWh, built up over the last few years, despite the tiny size of my solar array (2170 watts).]

I no longer track my EV usage but the numbers are there if I need them. As you may know, the energy pulled from "the wall" is more than the energy that gets to the battery (charging efficiency). A meter can be used to measure that number if it is of interest. Since I already had the meter in place — mounted and wired it myself — it was trivial to connect it when I made the switch to the 14-50 outlet.

While it was of interest to measure the charging efficiency of my LEAF — being an "early adopter" — with my Model S I am more inclined to just "get in and drive" after so many years of driving electric.
 
Yes, I have a meter to track my EV charging. You can buy a refurb utility meter from Hialeah Meter for relatively little. My power co-op has a net metering smart meter on my house, since I have solar panels. [I currently have a credit balance with them of 914 kWh, built up over the last few years, despite the tiny size of my solar array (2170 watts).]

I no longer track my EV usage but the numbers are there if I need them. As you may know, the energy pulled from "the wall" is more than the energy that gets to the battery (charging efficiency). A meter can be used to measure that number if it is of interest. Since I already had the meter in place — mounted and wired it myself — it was trivial to connect it when I made the switch to the 14-50 outlet.

While it was of interest to measure the charging efficiency of my LEAF — being an "early adopter" — with my Model S I am more inclined to just "get in and drive" after so many years of driving electric.

What have you found the charging efficiency to be? Maybe 85%? Presumably, total use at the service entrance would be another 2% higher due to line loss from the panel to the 14-50?
 
What have you found the charging efficiency to be? Maybe 85%? Presumably, total use at the service entrance would be another 2% higher due to line loss from the panel to the 14-50?
I haven't measured it for the Tesla. There wouldn't be any significant line loss for my outlet because the run is about two feet and I am using 6 gauge wire. One of these days I'll measure the efficiency, although my frequent opportunity charging makes it difficult to get good numbers over an extended period of time.

With a Tesla the efficiency could vary considerably depending on the temperature in the garage, since that affects battery cooling or warming.
 
What have you found the charging efficiency to be? Maybe 85%? Presumably, total use at the service entrance would be another 2% higher due to line loss from the panel to the 14-50?
With the caveat that this is only one tiny data point, I did an efficiency experiment today:

Charged to my usual 60% (at 240 V, 32 A, 7.7 kW)
Drove car, according to the trip data: 75.9 miles, 20.0 kWh, 264 Wh/mile
Charged back to 60%, wall meter said that I used 23 kWh and I'd guess that's ± 0.5 kWh (the meter readings are a bit coarse).

That works out to 87.0 ± 1.9% efficient. The way to drastically reduce those error bars is to do the experiment over a longer period of time, such as a week or a month. But I would have to forgo opportunity charging to do it and I am reluctant to do that.

There are numerous variables that will affect charging efficiency of a given size battery:

• Battery temperature: A cold battery will take extra energy to warm and a warm battery will take extra energy to cool.
• Charging speed: Faster charging means that the car systems run for a reduced time, leading to reduced overhead losses; very slow Level 1 charging at 120 V, 12 A is substantially less efficient than typical Level 2 charging.
• Battery SOC: Charging a battery near empty is more efficient than charging a battery near full (because the charge rate tapers but the overhead loss continues apace).
• Measurement error: Just how accurate is the usage data provided by the car?
• Preheating/precooling will, obviously, substantially reduce apparent charging efficiency.
• "Vampire" losses: How does one account for vampire losses when running the experiment over an extended period of time?
 
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Measurement error: The only way to get a real measurement is to install a metre on the wall. I always assume that car instrumentation is no better than 5%. Sometimes it's better but I don't count on it.

Vampire and preconditioning losses: The difference between the screen and the wall metre is as close as you can get.

The car's numbers adjusted by a fudge factor work well enough for practical purposes.
 
Measurement error: The only way to get a real measurement is to install a metre on the wall. I always assume that car instrumentation is no better than 5%. Sometimes it's better but I don't count on it.

Vampire and preconditioning losses: The difference between the screen and the wall metre is as close as you can get.

The car's numbers adjusted by a fudge factor work well enough for practical purposes.
I agree that the numbers are hard to pin down precisely, which is why I mentioned some of the sources of variability. But the question was asked about efficiency of charging, since I do have a wall meter:

View attachment 164967

So I tried to measure it as best I could. If I did it over a period of days or weeks I expect that the efficiency would drop because of the vampire losses.
 
You might like to add advice on UMCs. Many have been destroyed by people running them at 40A, and they get warm. They do not fail when run at 30A, which implies that they are underdesigned, for the sake of size and beauty.

Also there have been instances of plugs melting. This is due to either high resistance or loose connection, both of which can be deferred with lubrication. Not a good idea to lube the contacts with silicone grease, as it's a dielectric. Nor with mica powder. (the white powder lock lube) I use graphite lube (the black powder lock lube), which is conductive. Lubing the contacts -lightly- will help the connections last longer.
 
You might like to add advice on UMCs. Many have been destroyed by people running them at 40A, and they get warm. They do not fail when run at 30A, which implies that they are underdesigned, for the sake of size and beauty.

There are now (since the grey plug) very few reports of this. Not zero, but not like the originals which did heat up badly. I run 33 amps because 32 amps is supposed to be where the more efficient charging starts and because it will drop down to 30 amps if there is some problem. I don't think it drops down from 30 on a 14-50.
 
I cross posted this as well in Model S HPWC. Quick question (Dilemma) regarding the Tesla HPWC. Looking at installing the TESLA HPWC as a primary and the NEMA 1450 as a backup. My question is I've seen different responses in regards to the warranty on the HPWC. This is in advance of the vehicle order to get the 8911 Tax Credit before expiration at the end of 2016.
My understanding is if you purchase the HPWC separately from the vehicle order you only get a 1year warranty, whereas if you purchase it WITH the vehicle it is covered under the same warranty duration as the vehicle. I've read situations of Model S owners buying and installing the HPWC separate from the vehicle order/Purchase, having it fail and having to pay out of pocket to have it repaired or buy another replacement cable. Anyone purchasing it WITH the car has had it replaced multiple times under warranty after a year. Has anyone received direction from Tesla on this or have any experience with the above situations, or any knowledge of the warranty coverage?
In addition, my dilemma is buy the HPWC and have it installed now, get the Tax Credit and only have it warrantied for a year or wait, possibly NOT have the EV Charging Infrastructure Tax Credit renewed and lose that but have the HPWC warrantied longer if purchased under the Vehicle Purchase warranty.
Are these newer HPWCs more reliable now? I'm familiar with the earlier problems regarding fuse issues and such.

Skione65
 
I have no personal experience with lubricating electrical contacts, so I have to rely on sites that appear reliable. This site appears to be reliable and disputes your claim: Dielectric Grease vs Conductive Grease Can someone elaborate on this?

Interesting reading ...

The important physical characteristic is that any grease must have low enough viscosity to push out of the way at contact points, be water or liquid resistant, and be stable enough to remain in place as a protectant against moisture and air for a long time. It will not do any good to apply a grease that does not do required functions of excluding air and moisture, and lubricating the interface to prevent galling or fretting, for extended periods of time.
Contrary to silly Internet rumors and articles, silicone dielectric grease will NOT insulate pressure connections. Silicone dielectric grease will prolong connection life as well as, and have just as good conduction performance, as a properly selected metallic powder grease (conductive grease). On the other hand, and improperly selected "conductive" grease can actually cause connection problems.
 
I've perused this thread and a couple of others and haven't seen this situation addressed so I thought I'd post here. Any and all advice is much appreciated.

I'm thinking of installing a NEMA 14-50 receptacle now as I've been hemorrhaging cash lately, what with buying the Tesla and all. I would in all likelihood upgrade to a HPWC later this year. As luck would have it, my garage is on the exact opposite side of the house from the service entrance. Running along the exterior of the house would be a little over 100 feet. I believe my 200A service has headroom for 80A charging, but I'll have an electrician do the math.

I understand that to be ready to install the HPWC I should use at least AWG #3 wire for the run. The problem is that the only 14-50 receptacles I've seen are labeled "Wire Size Range AWG #10 - #4". Is there any way to do this? I'd also like to be able to remove the HPWC and replace it with the NEMA 14-50 if I move in the future.
 
I've perused this thread and a couple of others and haven't seen this situation addressed so I thought I'd post here. Any and all advice is much appreciated.

I'm thinking of installing a NEMA 14-50 receptacle now as I've been hemorrhaging cash lately, what with buying the Tesla and all. I would in all likelihood upgrade to a HPWC later this year. As luck would have it, my garage is on the exact opposite side of the house from the service entrance. Running along the exterior of the house would be a little over 100 feet. I believe my 200A service has headroom for 80A charging, but I'll have an electrician do the math.

I understand that to be ready to install the HPWC I should use at least AWG #3 wire for the run. The problem is that the only 14-50 receptacles I've seen are labeled "Wire Size Range AWG #10 - #4". Is there any way to do this? I'd also like to be able to remove the HPWC and replace it with the NEMA 14-50 if I move in the future.

Your #3 (or larger) run can terminate in a sub panel in your garage. Then you can have a breaker for your 14-50 and the appropriate wire and receptacle.