32amp Vs 48amp?

[100d]

My buddy who just got a rivian has offered me his wall connector white Tesla charger for $200.
I already have the 240 outlet and use the mobile charger every day.

I believe my electrician can install a plug for the wall connector to plug into that wall outlet for 100.

So my question is, is it worth spending the $300-350 to get a wall connector vs the mobile connector?

I think it’s 32amp vs 48 amp.

Thanks for your advice!

 

[jjrandorin]

Well,

Unless you have your electrician both add a pig tail to the wall connector AND update the wiring for your currently installed outlet (or verify that the previously installed outlet has existing wiring that can support the higher charging speed) the wall connector is going to charge at the exact same rate as the mobile connector.

 

[100d]

Well,

Unless you have your electrician both add a pig tail to the wall connector AND update the wiring for your currently installed outlet (or verify that the previously installed outlet has existing wiring that can support the higher charging speed) the wall connector is going to charge at the exact same rate as the mobile connector.

The pig tail was what he was charging me for I think. I believe the outlet is already 50amp. But assuming that is correct is it worth the expense?

 

[itch808]

I believe you need a 60amp breaker and supporting wiring that can handle 60amp to charge at the full 48amp

 

[jjrandorin]

If the outlet is 50amp, then you would be charging at 40 amp (not 48) due to the 80% rule. So, if the outlet is 50amp, you are choosing between your current mobile connector at 32 amp and the wall connector at 40 amp, or an 8 amp difference.

There are a couple different ways to look at this.

One is "Is there ever a time when the increase in charging speed is going to mean a difference to me"? Only you can answer that, but for the VAST majority of people, an 8 amp difference in charging speed isnt going to make a difference at all, so if "Its faster" is the only consideration, it probably isnt worth it.

The other is "do I just "want it" because I think it looks cool in my garage?" Note that I dont think there is a single thing at ALL wrong with that being the driver (because it looks cool), and in fact, I have (2) wall connectors in my garage, one for each vehicle, largely for that reason. Mine are hooked up in a power share of a 60amp circuit, for 48amp charging, but I dont "need" it to be that fast... I "wanted" it to be that fast.

There is zero wrong with getting something because you want it, at least to me, especially with these type of things, but I think its important to be honest with yourself and figure out if you need it, or just want it for "reasons" whatever those are, and decide accordingly.

 

[100d]

Understood. I guess I need to first find out if he put in a 60amp plug or 50amp plug.
It does look cooler but the truth is that’s not really the driving force behind getting it.
The driving force is it will be faster. But if I only have a 50 amp plug I agree it won’t be worth it.

How much of a difference is 32am vs 48amp as far as time is concerned?

 

[jjrandorin]

Well, this is the model S subforum. I dont have one of those (I have a 3 and Y) but the charging charts that Tesla has for wall connector speeds include model S.

You would be charging currently at 32amps if you are maxing out the mobile connector, so for a model S that looks like its "around" 27 MPH (or more accurately 7.7kW charge rate but its easier for most people to think in MPH even though its less accurate). I also said "around" because the model S in that chart is likely not a 100D.

You probably know how many MPH you charge at now, so if its not 27 its probably close to that.

You can see from the chart that the 50amp circuit (40amp charging) is listed at 34 MPH for a model S, so a difference of about 7MPH from what you have now. If you have the wiring to get the full 60amp circuit for 48amp charging, it would be "around" 41" so even if you are able to max it out, it would be around 14MPH faster.

Unless you are a tradesman who visits home a lot in between sales calls or something, or have a time of use plan where you need to fit all of your charging between midnight and 6amp (so charging speed matters in this case), that difference in speed likely makes very little difference for your day to day usage.


As for "difference in time" thats going to depend entirely on how much of your battery you drive out, but if you know that even at the fastest home charging speed for that wall connector, its about 14MPH faster, you can probably calculate the time difference for yourself.

Wall Connector Technical Details	Charge Speed Max Miles of Range per Hour of Charge*
Circuit breaker (amps)	Maximum output (amps)	Power at 240 volts (kilowatt)	Model S (mph)	Model 3† (mph)	Model X (mph)	Model Y† (mph)
60	48	11.5 kW	41	44	35	44
50	40	9.6 kW	34	37	29	37
40	32	7.7 kW	27	30	23	30
30	24	5.7 kW	21	22	17	22
20	16	3.8 kW	14	15	12	15
15	12	2.8 kW	10	11	9

 

[100d]

This is very helpful thank you!

Just one more question…how can I tell using the Tesla app how many miles per hour I am charging?

 

[brkaus]

Understood. I guess I need to first find out if he put in a 60amp plug or 50amp plug.
It does look cooler but the truth is that’s not really the driving force behind getting it.
The driving force is it will be faster. But if I only have a 50 amp plug I agree it won’t be worth it.

How much of a difference is 32am vs 48amp as far as time is concerned?

There really isn’t a commonly used 60a outlet & plug.

 

[100d]

I know nothing about electric so I have no idea how it even tell how
Many amps the plug is. I suppose I can look at the circuit box but that’s about it.

 

[jjrandorin]

This is very helpful thank you!

Just one more question…how can I tell using the Tesla app how many miles per hour I am charging?

for me, it says the charging speed right on the home page of the car screen when I am charging. I dont know if model S is different.

 

[100d]

This is what I see.

 

[Brass Guy]

To check your charging rate, just open the app while it's charging; it should say something like 27 mi/hr on the home screen.

Check the circuit breaker for that outlet. It could be a 40A or 50A breaker. This is because there isn't a 40A receptacle; so it is allowed to have a 50A outlet on a 40A circuit. The difference is the wiring. The 50A circuit must have heavier gauge wiring which of course costs more.
The 80% rule @jjrandorin mentioned means if it's a 40A circuit you can only draw up to a 32A continuous load on that circuit.

To to conclude, if it is a 40A circuit you will not gain anything. If it is a 50A circuit you should be able to increase your charging rate by 25%.

 

[100d]

It’s a 50 Amp circuit.
But doesn’t that mean I’ll only get a 40 amp charge vs 48 amp?

Also as I posted above on my home screeen of the app all I see is the amp rate it’s charging at not the miles per hour.

 

[mborkow]

Before you buy your friend’s used gear, check if your local power company offers rebates. Mine does, $500, which made a brand new one practically free.

 

[Brass Guy]

Also as I posted above on my home screeen of the app all I see is the amp rate it’s charging at not the miles per hour.

That's because it says Charging Complete. Check it while it's charging. You could just bump it up to 80% in the app and watch it for a minute or two, then you put it back to 70% after you read your charge rate.

(edit)
And yes, the wall connector on a 50A circuit will allow charging at 40A which is 25% more than the 32A you get with the mobile connector.

 

[Enadler]

One other thing to keep in mind. Do you travel with your mobile charger? If so, there is a small convenience factor and wear and tear factor of plugging and unplugging the charger and putting it away each time. For 9 years I did this but 2 years ago I got a HPWC and have found using it easier. Also, it does look better.

 

[100d]

One other thing to keep in mind. Do you travel with your mobile charger? If so, there is a small convenience factor and wear and tear factor of plugging and unplugging the charger and putting it away each time. For 9 years I did this but 2 years ago I got a HPWC and have found using it easier. Also, it does look better.

So as silly as this will sound. I actually have two mobile chargers. One I leave in my garage to charge and one I leave in the frunk.

So I’m thinking. That this is really A silly and anside from the cool looking factor not a practical addition. As I would just need to sell one of my mobile charger kits.

My electric company does offer rebates etc but the fine print I read said I would
Need to be on hourly rate pricing and to me that makes no sense as I pay more than 50 percent less at all times and don’t want to think about the electric in my house being charged at double the rate during the day.

 

[100d]

23 mph.

 

[jjrandorin]

So I’m thinking. That this is really A silly and anside from the cool looking factor not a practical addition.

Thats what I was saying up thread. There are very few circumstances where something like this would make sense other than "because I want it". If you are trying to find some other reason that makes sense, you probably wont find one.

You dont have a time of use electricity plan where you only get the lowest rates between midnight ant 6am.

It does not appear you have limited time at home to charge or share your charger with a bunch of other people where an extra 8-15 miles per hour would make a difference.

It does not appear you have a job where you drive a ton during the day AND go back home for charging.

You already have a 32amp circuit

You already have 2 mobile adapters

There isnt a single thing other than "I want it" that is going to make this make any kind of sense to do at all.