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What's up with HPWC?

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View attachment 180451 Got my HPWC install done today..now waiting for the Gecko Hose Clamps recommended by @systemcrashed to get delivered so the install gets its final touches.
And thanks to @CmdrThor for the tip to call local SC for the HPWC so I didn't have to wait three weeks.
I realized we are all "winding it wrong". We got to go counter clockwise for the end adaptor to attach at the HPWC slot a little less awkwardly :D
 
NEMA 14-50 needs to be installed with 50A breaker ... maximum charging is 40A. I have installed the Wall Charger and I have a 48A Model X. I don't see a huge advantage over using the 14-50 besides more organized with the Wall Charger and slightly faster. If you plan to get another Tesla in the future, it will be a big benefit to have 2 Wall Chargers as master/slave. In that case, why not get one for now ...

https://www.teslamotors.com/sites/default/files/downloads/US/charging_pdf_40amp_1450.pdf
I have the same rationale as you @pchan.
@jsollender I debated this long and hard and the summary is upthread for why I went with HPWC and spent $2200 vs. $350 on NEMA14-50 which would have simply worked out for my 48A X.
 
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I have the same rationale as you @pchan.
@jsollender I debated this long and hard and the summary is upthread for why I went with HPWC and spent $2200 vs. $350 on NEMA14-50 which would have simply worked out for my 48A X.

I was not planning to get the Wall Charger before they come up with the new version that has Slave/Master thing ... SM, why not? ;) I have reserved the 3 that might not even be delivered before 2020 to be the 'slave'. You can actually be very organized with the UMB charger and the slightly faster charging for 40A vs 48A is not worth the hassle to install a wall charger in my opinion.
 
Understanding this. So @TexasEV a 14-50 does not allow charging at 48 A? I thought the amperage was dependent on the fuse for the circuit, such that a 60 Amp fuse/circuit breaker/whatever you call it allows peak of 60 amps but sustained at 75% which is why the cars charge at 48 Amp. Just like a 100 Amp circuit allows the 72Amp charger upgrade to work. Are you right that the 14-50 does not allow 48 Amp through it?

It's simple: 48A charging is a continuous load, therefore all circuit components (conductors, breakers, and equipment) must be rated at 125% of that, or 60A. A NEMA 14-50 is, by definition, rated for 50A maximum. 50 < 60. :)

Tesla does not make a portable cord set capable of charging at more than 40A.
 
Okay, so I read through this ENTIRE thread...and have a couple of questions about my upcoming installation.

We own a 44-yr old home with a Federal Pacific Breaker Box. All electric service, no gas at all. We have 200 amp service currently.
Don't plan on living here more than a few more years though...

Sounds like the wall charger is probably the better option, as we have a deposit for a Model 3 as well...and we can take it with us to the next house. One of the bids show upgrading the service to 225amp: Install 2pl50A GE breaker inside interior main panel and to install Tesla WC on front right interior garage wall (front load)=25RPH.

Trying to decipher if this means it will be on a 50amp circuit, and if so, should I ask to change it to 100amp--would this give us future use to charge the Model 3 if/when that time comes in this house? Would it save any time/money? Besides being able to fully utilize the 48amp charging capability vs 40amp with the 50amp circuit (albeit a small benefit).

I don't know the technical terms for what I'm asking, so please forgive my lack of knowledge...y'all are much more knowledgeable, that's why I'm asking...
 
Okay, so I read through this ENTIRE thread...and have a couple of questions about my upcoming installation.

We own a 44-yr old home with a Federal Pacific Breaker Box. All electric service, no gas at all. We have 200 amp service currently.
Don't plan on living here more than a few more years though...

Sounds like the wall charger is probably the better option, as we have a deposit for a Model 3 as well...and we can take it with us to the next house. One of the bids show upgrading the service to 225amp: Install 2pl50A GE breaker inside interior main panel and to install Tesla WC on front right interior garage wall (front load)=25RPH.

Trying to decipher if this means it will be on a 50amp circuit, and if so, should I ask to change it to 100amp--would this give us future use to charge the Model 3 if/when that time comes in this house? Would it save any time/money? Besides being able to fully utilize the 48amp charging capability vs 40amp with the 50amp circuit (albeit a small benefit).

I don't know the technical terms for what I'm asking, so please forgive my lack of knowledge...y'all are much more knowledgeable, that's why I'm asking...
Yes, that would only be for a 50A circuit on a wall connector. Given an all electric house, you probably have large loads (heating and water heating) that eat up a lot to most of your load calc, leaving not much left to charge a car.

The good news for you is that if you only have 50A of headroom total, a master/slave wall connector would allow you to actually charge two cars at once, either one utilizing the full amount when possible. The alternative would be to manually ensure they never charge at the same time (yikes, that would be hard to ensure you don't screw up), or have two smaller charging circuits like a 6-20, and neither car would be able to charge at even reasonable speeds.

Also, I hope I didn't give the impression that it's cheap/easy to uninstall a wall connector and take it to your next home. My situation is fairly unique that I'm not an electrician myself, but grew up in a family of electricians so I'm familiar with things, and comfortable doing work myself with supervision from brothers/dad that are licensed electricians. Actually paying an electrician to uninstall a wall connector and blank it off/convert to a 14-50 would probably be a good portion of the cost of just buying a new one.
 
@FlasherZ, or anyone that has actually done a master/slave installation, what kind of wire did you use for the data bus? I know the manual just says a single twisted pair. So I'm thinking either just one pair out of a CAT5 (or CAT3 if you still carry that around), or go with something a bit larger gauge like doorbell or alarm wire?
 
Yes, that would only be for a 50A circuit on a wall connector. Given an all electric house, you probably have large loads (heating and water heating) that eat up a lot to most of your load calc, leaving not much left to charge a car.

The good news for you is that if you only have 50A of headroom total, a master/slave wall connector would allow you to actually charge two cars at once, either one utilizing the full amount when possible. The alternative would be to manually ensure they never charge at the same time (yikes, that would be hard to ensure you don't screw up), or have two smaller charging circuits like a 6-20, and neither car would be able to charge at even reasonable speeds.

Also, I hope I didn't give the impression that it's cheap/easy to uninstall a wall connector and take it to your next home. My situation is fairly unique that I'm not an electrician myself, but grew up in a family of electricians so I'm familiar with things, and comfortable doing work myself with supervision from brothers/dad that are licensed electricians. Actually paying an electrician to uninstall a wall connector and blank it off/convert to a 14-50 would probably be a good portion of the cost of just buying a new one.
My husband wants to just install a NEMA 14-50 plug and be done with it, LOL. He also wants to keep this house as a rental. I told him all the more reason to get the service upgrade!

So you don't think it's worth the extra cost/effort to get a 60amp circuit or 100 amp circuit? Overkill? Not needed if we want to daisy chain later?
 
My husband wants to just install a NEMA 14-50 plug and be done with it, LOL. He also wants to keep this house as a rental. I told him all the more reason to get the service upgrade!

So you don't think it's worth the extra cost/effort to get a 60amp circuit or 100 amp circuit? Overkill? Not needed if we want to daisy chain later?
It totally depends on the situation (most importantly underground vs. overhead service), but a service upgrade can be very expensive. I only have 50A of headroom in my own load calc, and with a short term outlook of still living here (even with keeping as a rental), I don't personally feel it's worth the service upgrade (and I already ran the garage circuits in only 6-3 NM, cause anything larger would have been extraordinarily difficult to fish in).
 
Understanding this. So @TexasEV a 14-50 does not allow charging at 48 A? I thought the amperage was dependent on the fuse for the circuit, such that a 60 Amp fuse/circuit breaker/whatever you call it allows peak of 60 amps but sustained at 75% which is why the cars charge at 48 Amp. Just like a 100 Amp circuit allows the 72Amp charger upgrade to work. Are you right that the 14-50 does not allow 48 Amp through it?
The 50 in 14-50 means 50A circuit. You can only draw 40A continuously from a 50A circuit, and the 14-50 UMC adapter is limited to 40A. If you want to charge at 48A you need a HPWC or high amp J1772. The charging page on the Tesla web site explains this, as does the PDF that pchan linked to above.

If you want a 60A circuit and charge at 48A you need to install a HPWC. The UMC maxes out at 40A charging.
 
My husband wants to just install a NEMA 14-50 plug and be done with it, LOL. He also wants to keep this house as a rental. I told him all the more reason to get the service upgrade!

So you don't think it's worth the extra cost/effort to get a 60amp circuit or 100 amp circuit? Overkill? Not needed if we want to daisy chain later?
I think it's overkill unless you're getting two EVs. Your car will charge fully overnight at 40A using the 14-50 outlet. Yes it will finish charging sooner on a 60A or 100A circuit, but as long as it's finished charging by morning why would you pay more to have it finish charging a little faster? Do you know what time your smartphone finishes charging when you plug it in at night? I don't, and I don't care as long as it's fully charged when I wake up. Having the higher amp charger in the car can be useful when traveling, but it's not usually an issue at home.
 
I suppose that the 14-50 should suffice. I'm not worried about the plug location as it won't get bumped and will sit at a level where my tablesaw is so it won't droop. I can always upgrade to the HPWC down the road as long as the cables are the right gauge for the larger amperage, right?
 
It totally depends on the situation (most importantly underground vs. overhead service), but a service upgrade can be very expensive. I only have 50A of headroom in my own load calc, and with a short term outlook of still living here (even with keeping as a rental), I don't personally feel it's worth the service upgrade (and I already ran the garage circuits in only 6-3 NM, cause anything larger would have been extraordinarily difficult to fish in).
It's overhead service...should we be concerned about fire hazard from the Federal Pacific Box? Someone mentioned using mobile charger not good for long term use? Do most people leave it plugged into the wall at home or unplug every morning and leave in the car?

I don't want to spend more money than I have to...if installing just a plug will suffice then fine. No need to get all fancy. We do plan on getting another EV, but by then we may be in another house...
 
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It's overhead service...should we be concerned about fire hazard from the Federal Pacific Box? Someone mentioned using mobile charger not good for long term use? Do most people leave it plugged into the wall at home or unplug every morning and leave in the car?

I don't want to spend more money than I have to...if installing just a plug will suffice then fine. No need to get all fancy.
Overhead means it's easier to actually upgrade the service if you really need to (don't have to trench and re-landscape if necessary). I don't know about federal pacific (my own experiences are almost all with Square D; I know Zinsco is the red flag word for replace-if-you-ever-touch). If you're having to unplug your mobile connector to take with every day to charge elsewhere, you should probably get a wall connector for home. Most people that use a 14-50 at home leave it plugged in semi-permanently. Given no available load calc to go higher than 50A, not planning on being in the house for for more than a year or two, no need to routinely use the mobile connector elsewhere, and wanting to be price conscious, I'd say a 14-50 fits your needs just fine (if all my assumptions are correct). If you get a Model 3 before you move, or you find that you're pulling the 14-50 out daily (intentionally or unintentionally), then you can re-evaluate.
 
@FlasherZ, or anyone that has actually done a master/slave installation, what kind of wire did you use for the data bus? I know the manual just says a single twisted pair. So I'm thinking either just one pair out of a CAT5 (or CAT3 if you still carry that around), or go with something a bit larger gauge like doorbell or alarm wire?

Ideally, twisted-pair would be used. But I'm pretty sure your basic 18 AWG thermostat wire will work, too. I tend to carry a box of CAT5E around with me, so that's what I'd use.
 
Overhead means it's easier to actually upgrade the service if you really need to (don't have to trench and re-landscape if necessary). I don't know about federal pacific (my own experiences are almost all with Square D; I know Zinsco is the red flag word for replace-if-you-ever-touch). If you're having to unplug your mobile connector to take with every day to charge elsewhere, you should probably get a wall connector for home. Most people that use a 14-50 at home leave it plugged in semi-permanently. Given no available load calc to go higher than 50A, not planning on being in the house for for more than a year or two, no need to routinely use the mobile connector elsewhere, and wanting to be price conscious, I'd say a 14-50 fits your needs just fine (if all my assumptions are correct). If you get a Model 3 before you move, or you find that you're pulling the 14-50 out daily (intentionally or unintentionally), then you can re-evaluate.

So is it really okay to use the mobile connector on a daily basis? I had the impression that it was supposed to stay in the car....sounds like it could just stay plugged into the wall...and your assumptions are correct :)
 
It's overhead service...should we be concerned about fire hazard from the Federal Pacific Box? Someone mentioned using mobile charger not good for long term use? Do most people leave it plugged into the wall at home or unplug every morning and leave in the car?

I don't want to spend more money than I have to...if installing just a plug will suffice then fine. No need to get all fancy. We do plan on getting another EV, but by then we may be in another house...

FPE panels are a disaster waiting to happen. My home in California nearly burned because of an FPE breaker that failed to trip. There are plenty of resources online that talk about these panels -- frankly, I wouldn't charge a Tesla from one of them without another form of inline overcurrent protection (e.g., another breaker used as a disconnect).

Is My Electrical Panel Safe? - Important Information About Federal Pacific Electric, Zinsco and Outdated Electric Panel Boxes