Charger Install Help

[cwallace]

We are picking up our first Tesla (M3RWD) tomorrow a couple weeks earlier than initially expected so I am scrambling a bit to get a charger installed. I've had two contractors out to give me estimates. The first quoted a 60A breaker and charging station install for $700. The second (from the Tesla certified list) quoted a 40A breaker and charging
station install for $810. Now here is where it gets tricky. Both noted my limitations due to our outdoor breaker. The first (60A) said that he could installed the breaker and then if I had issues with tripping, then I could just scale the amperage down on the charger. The second said that 40A would be max AND I would need a DCC Load Management module for $1,300. We don't currently have any issues outside of the occasion GFCI outlet trip in the garage which has the garage door opener and various battery chargers. The 40A breaker would charge plenty fast (my wife's daily roundtrip would be around 50 miles) and it is unlikely we will travel much in it outside of short day trips. I would obviously prefer to avoid the load management module, but I will bite the bullet if needed. I am just trying to avoid being upsold something. I would appreciate any help.
.

 

[Sophias_dad]

Several comments:

Get someone to do a real load calculation. You should be more than fine with a new 60 amp breaker in the outdoor panel. I see 200 in and 80+30+20(on one leg only, which leaves you 70 amps duplex breaker left(200-80-30-20), even without any possibility to trip. (Yes, purists would say I should do a real load calculation based on the square foot and large loads and all that, but that 80+30+20 is the absolute maximum that could be getting used of that 200).

A DCC in this circumstance is entirely uncalled for, presuming you plan to go from the outside panel. Its also unreasonable to do for the inside panel, for the below reasons.


You actually don't NEED any new charging at all. 12 hours a night of 5mi/hr is 60 miles. Done! If you happen to have a 5-20 outlet, that's even better, at 7mi/hr.

If you want a little headroom in charging and must go off the indoor panel, just accept a 20 or 30 amp 240 volt outlet, which will give you double or more of the charging you need.

 

[PdxAmp]

Several comments:

Get someone to do a real load calculation. You should be more than fine with a new 60 amp breaker in the outdoor panel. I see 200 in and 80+30+20(on one leg only, which leaves you 70 amps duplex breaker left(200-80-30-20), even without any possibility to trip. (Yes, purists would say I should do a real load calculation based on the square foot and large loads and all that, but that 80+30+20 is the absolute maximum that could be getting used of that 200).

A DCC in this circumstance is entirely uncalled for, presuming you plan to go from the outside panel. Its also unreasonable to do for the inside panel, for the below reasons.


You actually don't NEED any new charging at all. 12 hours a night of 5mi/hr is 60 miles. Done! If you happen to have a 5-20 outlet, that's even better, at 7mi/hr.

If you want a little headroom in charging and must go off the indoor panel, just accept a 20 or 30 amp 240 volt outlet, which will give you double or more of the charging you need.

I agree with this. I used a standard outlet that added about 4,5mi/hr for a few weeks. Just recently i installed a 6-20 outlet on an existing 240v/20amp circuit and it's charging at ~ 15miles/hr ....plenty for my needs. cost me $30 for outlet and $35 for Tesla adapter for the mobile charger.

 

[Sophias_dad]

And of course, reading the first post in detail.... The M3RWD will only have a 32 amp charger onboard, so there's absolutely no charging speed difference between the 40A and 60A circuit. The latter will just make your wallet lighter.

 

[father_of_6]

The 60amp will be more future proof... the AWD Model 3 charges at a max of 48amps, which requires a 60amp circuit (because it's continuous load).

While you *could* get by charging on a standard 15A/20A outlet, the 240v will make you feel more like a man. On those occasions where you need to charge quickly, you'll have it. Also in very cold climates, 15A/20A can struggle to warm the battery up enough to take a charge.

My vote is for 60A. Not sure how your 40A quote is more than the 60A quote. 60A FTW!

 

[Cosmacelf]

We are picking up our first Tesla (M3RWD) tomorrow a couple weeks earlier than initially expected so I am scrambling a bit to get a charger installed. I've had two contractors out to give me estimates. The first quoted a 60A breaker and charging station install for $700. The second (from the Tesla certified list) quoted a 40A breaker and charging
station install for $810. Now here is where it gets tricky. Both noted my limitations due to our outdoor breaker.

What limitations of the outdoor breaker??? You've got a 200A panel that at max load only serves 80+30 = 110A. You can easily put it a 60A breaker in that outside panel. I am presuming here that the 60A breaker would be installed in the outdoor panel, right?

The first (60A) said that he could installed the breaker and then if I had issues with tripping, then I could just scale the amperage down on the charger. The second said that 40A would be max AND I would need a DCC Load Management module for $1,300.

The second guy is shaking you up for more money.

We don't currently have any issues outside of the occasion GFCI outlet trip in the garage which has the garage door opener and various battery chargers.

If GFCIs trip, it is usually because they are getting old. Replace it with a new one, and the problems should go away.

Anyways, go with the first electrician.