Home Charging

[Tasdevil]

So, why derate the charging capacity of the wall unit?

You should ask your electrician why he did that.
And if your not 100% happy with his answer ask him to come over and put an amp meter on the circuit on a day when you are charging. Then see how much current it draws on the 20A setting and then try the 32A setting. The process should only take 15mins and if the 32A setting works ok then he should be able to leave it like that.

 

[miimura]

The derating and the accompanying description of switch settings and breaker ratings is set forth in the Tesla manual for the Wall Connector. They are clearly following the USA National Electric Code convention and carried it over to other markets.

 

[meloccom]

The derating and the accompanying description of switch settings and breaker ratings is set forth in the Tesla manual for the Wall Connector. They are clearly following the USA National Electric Code convention and carried it over to other markets.

I have talked to the new guy responsible for charging development in Australia and he is working on local install instructions for Aus\NZ so its likely that the electrician has derated it as described in the USA instructions as that is all that is currently available. IIUC in Australia no such derating will be required as all our standards refer to continuous load. @Dborn contact Tesla and the new guy should be able to sort out the confusion.
Please note I am not an electrician and you should always seek professional advice, the above is opinion only.

 

[Dborn]

The big question is:- are these wall units the same ones being delivered in China/Hong Kong, or have they been tweaked for Australia. Short answer - I don't know. The unit looks identical inside and out to the HK one, whose manual I have. The problem I see, is that the amperages available in HK unit do not match ours. If one derates according to the HK manual, then circuit breakers are listed as 50, 40, 20, and 16. Derating means the unit is set one lower as follows 40, 32, 16 and 10. (quoting directly from the manual) So, with the 32 amp breaker i have, that means the unit is set to 16 amps. Not good. If it was 20 amps, then that is just about acceptable given the circuit i have in position. There is no information on any label on the unit. I have looked. The carton it came in also had zero information on it, not even that it was a 240 volt unit! Or that it was for this or any other market.
Mitchell was here for that part of the install, as mine is apparently the first wall unit to be installed in a customers house in the country. He wanted to ensure the DIP switches are set correctly. They are, set for 16 amps as per the HK manual. (or 20amps if this is indeed a tweaked unit for Australia). Mitchell thought that it was set for 20 amps. ( The difference is just under a kilowatt!!) Perhaps the only way i will find out is when a test car is left here overnight for testing, possibly within the next 2-3 weeks. Then i can look at the display and try and see what level it is charging at.

 

[miimura]

The big question is:- are these wall units the same ones being delivered in China/Hong Kong, or have they been tweaked for Australia. Short answer - I don't know. The unit looks identical inside and out to the HK one, whose manual I have. The problem I see, is that the amperages available in HK unit do not match ours. If one derates according to the HK manual, then circuit breakers are listed as 50, 40, 20, and 16. Derating means the unit is set one lower as follows 40, 32, 16 and 10. (quoting directly from the manual) So, with the 32 amp breaker i have, that means the unit is set to 16 amps. Not good. If it was 20 amps, then that is just about acceptable given the circuit i have in position. There is no information on any label on the unit. I have looked. The carton it came in also had zero information on it, not even that it was a 240 volt unit! Or that it was for this or any other market.
Mitchell was here for that part of the install, as mine is apparently the first wall unit to be installed in a customers house in the country. He wanted to ensure the DIP switches are set correctly. They are, set for 16 amps as per the HK manual. (or 20amps if this is indeed a tweaked unit for Australia). Mitchell thought that it was set for 20 amps. ( The difference is just under a kilowatt!!) Perhaps the only way i will find out is when a test car is left here overnight for testing, possibly within the next 2-3 weeks. Then i can look at the display and try and see what level it is charging at.

As you rightly point out, a 32A breaker is a particularly bad choice if any derating must be applied because of the huge gap in available switch settings between 20A and 40A. The car will only get 50%! I pointed this out during the discussion of using a plug and socket with this unit. Hopefully they will come out with a Australia/New Zealand version of the manual and revise the section on breakers and switch settings. Here is the page from the Hong Kong/China manual for reference.

As you can see, the top switch indicates Split Phase/Single Phase and the lower three switches are just ordinal identification 1, 2, 3, 4. There are three more possible settings for those three switches, so if they continue to recommend derating, they should just revise the firmware to insert another value to allow 32A breakers. That would allow 25A to the car - a huge 56% increase from 16A.

 

[Dborn]

As you rightly point out, a 32A breaker is a particularly bad choice if any derating must be applied because of the huge gap in available switch settings between 20A and 40A. The car will only get 50%! I pointed this out during the discussion of using a plug and socket with this unit. Hopefully they will come out with a Australia/New Zealand version of the manual and revise the section on breakers and switch settings. Here is the page from the Hong Kong/China manual for reference.

View attachment 51527

As you can see, the top switch indicates Split Phase/Single Phase and the lower three switches are just ordinal identification 1, 2, 3, 4. There are three more possible settings for those three switches, so if they continue to recommend derating, they should just revise the firmware to insert another value to allow 32A breakers. That would allow 25A to the car - a huge 56% increase from 16A.

Precisely. However, there is no indication one way or the other whether or not this applies to our unit. There was NO manual with the unit!!! My comments are taken from the Hong Kong manual and the page you have provided. I guess we need to ask Palo Alto. Question is, whom do we contact?

 

[markwj]

Precisely. However, there is no indication one way or the other whether or not this applies to our unit. There was NO manual with the unit!!! My comments are taken from the Hong Kong manual and the page you have provided. I guess we need to ask Palo Alto. Question is, whom do we contact?

For HK owners, an electronic version of the manual is available in My Tesla on the Tesla website.

 

[Dborn]

For HK owners, an electronic version of the manual is available in My Tesla on the Tesla website.

under which heading?

 

[markwj]

under which heading?

After sign-in, View Profile (next to Model S), then scroll down to Documents and choose 'Model S Guides'. Mine shows:

Wall Connector Installation Guide - Hong Kong
5/23/20141.8 MB

 

[Dborn]

Yeah, mine is blank. Not a single document. By the way, do you have a delivery date published anywhere in my dashboard?

 

[Johnwill]

So, I have also been told that the wiring rules state that the breaker installed must be capable of the rated sustained load. So, why derate the charging capacity of the wall unit?

As the wall unit is basically a switch, which miimura kindly confirmed, then it must be able to handle it's maximum throughput 40A. If you are not conducting the full load that the switch can carry then there is no chance of damage to the wall unit. That only leaves protection of the cable and preventing the load continually tripping and damaging the MCB.
Our regulation for protecting a circuit with an MCB is the load must be less than or equal to the size of the MCB which must be less than or equal to current carrying capability of the cable.
The DIP switches tell the car what the chargers can draw. You should be able to set the DIP switch to draw a maximum of 32A which is less than or equal to a 32A MCB protecting a cable that can carry 32A or more.
What may make this unworkable is if there is any inrush to the inboard charger when the wall unit contractor closes. This would cause the MCB to trip on start up so hence the need for the derating.


It would be nice if the DIP settings available gave more options that matched the range of local MCBs. Most domestic units are C curve and range from 1A to 63A. For the wall unit these sizes could be a selection of either 10, 16, 20, 25, 32, 40 or 50.

 

[Johnwill]

The sparky has looked at my place and also been out to visit Tesla.
He tells me that it will cost around $3k to go 3 phase, but needs to put a quote together. Meanwhile he suggested that I make a list of all of the outlets etc in the house to calculate what the real load would be.
I've done that and created a google calc sheet for it. On the sheet I also looked at the current switchboard and did a worst case and sensible load calc.

In the worst case I'd be at home on a cold night with the air conditioning pumping heat, with the dishwasher running and cooking dinner in the electric oven, making coffee using the machine and the microwave, the stereo playing a movie on my plasma while the off peak hot water kicks in. This is pretty unlikely, but adds up to 77.5A. A more realistic estimate would be around 40A, for a short time, say making coffees with the movie playing, air-co pumping warm air and the off peak hot water heating up.

This is telling me that I might be able to get away with a single phase 32A in the garage without having to go 3 phase. I'll have the dual chargers for travel, but probably won't need the HPWC installed at home.
You can look at my calcs at Google Sheets - create and edit spreadsheets online, for free.

Either way, it'll be interesting to see what the sparky comes back with.

The Maximum Demand calculation, based on your spreadsheet, for a domestic installation with all the load on a single phase is:

Group A, Lights (3A 1-20, 2A every other 20 or part of)
20 lights = 3A

Group B, Power Points (10A 1-20, 5A every other 20 or part of)
20 doubles = 40 power points = 10+5 = 15A

Group C, Range (50%)
Oven 12.5A = 12.5 x 0.5 = 6.25A

Group D, Fixed Heating/Air Conditioning (75%)
Air Con 24A = 24 x 0.75 = 18A

Group F, Storage Water Heater (100%)
Hot Water 15A = 15A

Total = 3+15+6.25+18+15 = 57.25A

I hope that helps.

 

[Dborn]

As the wall unit is basically a switch, which miimura kindly confirmed, then it must be able to handle it's maximum throughput 40A. If you are not conducting the full load that the switch can carry then there is no chance of damage to the wall unit. That only leaves protection of the cable and preventing the load continually tripping and damaging the MCB.
Our regulation for protecting a circuit with an MCB is the load must be less than or equal to the size of the MCB which must be less than or equal to current carrying capability of the cable.
The DIP switches tell the car what the chargers can draw. You should be able to set the DIP switch to draw a maximum of 32A which is less than or equal to a 32A MCB protecting a cable that can carry 32A or more.
What may make this unworkable is if there is any inrush to the inboard charger when the wall unit contractor closes. This would cause the MCB to trip on start up so hence the need for the derating.


It would be nice if the DIP settings available gave more options that matched the range of local MCBs. Most domestic units are C curve and range from 1A to 63A. For the wall unit these sizes could be a selection of either 10, 16, 20, 25, 32, 40 or 50.

View attachment 51550

Thanks for the explanation. The sparky has fitted 32 amp D curve cb to account for that current inrush. Mainly applies to electric motors, though, doesn't it?

 

[JOH]

1 Phase only in Aus?

I just noticed that the Tesla specs for EU state either single phase or 3 phase charging will be available, but the HK and AU sites seem to show only single phase. Has TESLA communicated any specifics as to this for Aus and home charging?

EU site: Model S Specs and Standard Features | Tesla Motors
HK Site: Model S Specs and Standard Features | Tesla Motors
AU site: Model S Specs and Standard Features | Tesla Motors

- - - Updated - - -

I came across a link to the HK Home Wall Charger installation manual. Unfortunately, when I tried to paste here, it failed to successfully resolve to the correct page. I have a copy downloaded. Is there a way to paste attachments to this forum? Failing that I can email if anyone has an interest in seeing what they are sending to HK.

Will Tesla provide something similar for Aus?

Note: I am neither an electrician nor qualified to provide any electrical advice. I'm providing this post for discussion purposes only. Please contact a qualified electrician to perform any electrical work.

 

[MDK]

There is more info on the Design Studio: http://www.teslamotors.com/en_AU/models/design

Both 80 amp single phase and 32 amp three phase connectors are under development and will be available in early 2015.
For customers taking delivery before early 2015, a temporary 40 amp single phase connector will be provided

 

[JOH]

Thank you. Any idea what the following statement means - also from the Tesla Design page?

"For charging on the go, Model S is compatible with public charging stations using an IEC 62196 standard."

I was told that initially there would be no mobile charging solution and that would come early 2015. The statement above seems to indicate otherwise.


Just found this additional info.....so it seems we may be able to use the ChargePoint infrastructure while we await further charging solutions from Tesla.

Apparently, the company “will develop, in time, a Supercharger network in Australia.” Those Superchargers shouldn’t be expected until at least early 2015, and that’s an estimate rather than a confirmed timeframe. For anyone that buys a Model S early, the car will also recharge at public EV charging stations using the IEC 62196 standard connector, used at ChargePoint and some other privately-run installations.
Beyond that, there’s a bit more clarity on Australian home charging for the cars. All Model S vehicles sold in Australia will use the same connector as EU-delivered cars, compatible with single- and three-phase power, and the car’s onboard charger is matched with a bundled 40-amp wall charger (with no house re-wiring needed). For any Australian charging station that doesn’t use the IEC 62196 standard, an adapter will be sold in early 2015.

 

[MDK]

The car is fitted with a socket compatible with IEC 62196 "Mennekes type 2", same as in Europe, as opposed to the proprietary Tesla connector used in North America

That means the car can be charged at type-2 charging stations with a suitable cable. The question remains if a type2-type2 cable will be provided (free from Tesla in the UK) or if we have to buy them separately.

There's about a dozen type-2 charging stations in the Perth Metro area versus five J1772 (type-1) (listed on PlugShare)

There's more info at the Mobile Charging thread: http://www.teslamotorsclub.com/showthread.php/31341-Mobile-charging-for-Australia

 

[Dborn]

Ok, this is on good authority. A 40amp wall connector comes with the car at present. Mine has been installed. What is not clear is whether it is the same one going into HK or if it has been tweaked for Australia. There IS a difference! Next year, those with dual chargers, will be offered a straight swap to either a 32 amp 3 phase connector or an 80amp single phase unit. Both of these are currently under development. At some point superchargers will come here, possibly some time next year. The car has a type 2 Mennekes socket or otherwise known as IEC 62196. Tesla will not be supplying an adaptor from J1772 plug, which many chargepoint stations have in NSW. DavidRM has sourced an adaptor cable and is yet to test it. A 10amp mobile connector will also become available next year sometime.
Otherwise, see my posts above. Some of this info comes from Jerome, via JB Straubel via email to me, and some comes from the unit itself which is at my home. The rest comes from the web site. What is not clear is when the various items scheduled for next year will become available. They are talking about Q1, but from experience, I would add serious "Tesla time" to that.

 

[Johnwill]

Thanks for the explanation. The sparky has fitted 32 amp D curve cb to account for that current inrush. Mainly applies to electric motors, though, doesn't it?

You're welcome. Yes D curve tripping is 10 to 14 times instantaneous current as opposed to the standard C curve which is 5 to 10. D are usually used on high surge circuits, welders, transformers, motors, etc.

As the onboard chargers can be software controlled I'd be surprised if they didn't ramp them up.

Why you must limit the charging current when you have a cable and MCB capable of 32A is something you should definitely ask Tesla.

- - - Updated - - -

The car has a type 2 Mennekes socket or otherwise known as IEC 62196.

do you mean Aus and NZ cars will be the same as UK cars with this connector?

Oops. Didn't read the fine print I guess this answers my question.

All Model S vehicles sold in Australia will use the same connector as EU-delivered cars, compatible with single- and three-phase power, and the car’s onboard charger is matched with a bundled 40-amp wall charger (with no house re-wiring needed)

For the 230V 80A (18.4kW) and 400V 32A (22kW) options the onboard chargers must be rated for a different input than the US 120V/240V units.

 

[Dborn]

The connector is very similar but it has a shroud with slots, presumably to allow it to be locked in while the vehicle is charging. The pin layout and the flat is identical.