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I think it is a step function if the EVSE detects resistance in a certain band it selects the appropriate current by sending a mark-space ratio square wave to the car charger. The choices would be 32A, 16A, 10A, 7A I think. If the EVSE and lead are both 32A then the mark-space will be for 32A but the car charger will only draw 16A if it is a 3.3 car.
The square-wave sent by the EVSE to the car is a continuous function - you can signal any value you like between 6A and 80A with no steps as it's an analogue value.

The car itself isn't obliged to follow the signal precisely, merely to keep its total consumption below the value signalled by the EVSE (you could imagine a very simple design at the car end with two 6A chargers - one of them turned on all the time, the other turned on only when the EVSE signalled 12A or more). In practice, most cars seem to be more flexible than that and offer either continuously variable control or fairly fine steps (I don't have detailed info for the Leaf).

The resistors used for cable identification by the EVSE do have a limited number of steps specified in the standards - probably too crude to be very useful for solar charging, but in theory available on any socketed EVSE.

The resistors used by Mainpine on their controllers are a proprietary design feature by Mainpine so they can in principle do anything they like in their software, though apparently limited to a modest number of steps in current versions.
 

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My 2013 Leaf S does not display 3.3 and 6.6. Rather, it displays 120V and 240V, each with associated indicator for time needed to fully charge, by time - example: 240V 1.5 hours 120V 2.5 hours

Does this indicate the vehicle has a 3.3 or 6.6 charger? Color me stymied!
 

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My 2013 Leaf S does not display 3.3 and 6.6. Rather, it displays 120V and 240V, each with associated indicator for time needed to fully charge, by time - example: 240V 1.5 hours 120V 2.5 hours

Does this indicate the vehicle has a 3.3 or 6.6 charger? Color me stymied!
Images below, however improvements could have been implemented for different model years.

This image below looks like your description and I would say it has only a 3.3KVA



I would say that this image below shows a LEAF with the 6.6KVA as clearly shown.

 
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[...]
The Nissan Leaf has two options, 3.6 kW or 6.6 kW onboard charger.

230 volts at 16 amps is 3680 watts or 3.68 kW, just enough to supply a 3.6 kW Leaf at maximum power.

230 volts at 32 amps is 7360 watts or 7.36 kW, so this is what you need to supply a 6.6 kW onboard charger equipped Leaf at it's full capacity.

[...]
I live in the USA, where we have 120 or 3 phase 240V outlets and my car has 3,6 kW charger. When I would install 240V power outlet do I need that 30 amps unit, or 16 amps would be sufficient? Would I benefit from the stronger "feeder", or is it wasting of money?
 

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I live in the USA, where we have 120 or 3 phase 240V outlets and my car has 3,6 kW charger. When I would install 240V power outlet do I need that 30 amps unit, or 16 amps would be sufficient? Would I benefit from the stronger "feeder", or is it wasting of money?
Depends whether you want to future-proof your installation for your next car which almost certainly will need the higher current.
 

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Reading this thread has got me thinking as I was sold a Leaf with a 3.3kW yet my display shows both (which I thought was just Nissan's way of rubbing my nose in it).

I cannot see the label that Cath has mentioned so I will just have to buy a fast charger cable and test it out for myself.
Not sure if this has been clearly answered, would a 3.3kW also show the 6.6kW time on the display when not charging?
 

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Reading this thread has got me thinking as I was sold a Leaf with a 3.3kW yet my display shows both (which I thought was just Nissan's way of rubbing my nose in it).

I cannot see the label that Cath has mentioned so I will just have to buy a fast charger cable and test it out for myself.
Happy days. You have the 6.6 car for the price of a 3.3. Not the first time this has happened. When it occurs the other way round the buyer complains natrually but gettting an expensive option for free is great. Originally the car should have come with a fast charge lead. What have you got lead wise?
 

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The square-wave sent by the EVSE to the car is a continuous function - you can signal any value you like between 6A and 80A with no steps as it's an analogue value.

The car itself isn't obliged to follow the signal precisely, merely to keep its total consumption below the value signalled by the EVSE (you could imagine a very simple design at the car end with two 6A chargers - one of them turned on all the time, the other turned on only when the EVSE signalled 12A or more). In practice, most cars seem to be more flexible than that and offer either continuously variable control or fairly fine steps (I don't have detailed info for the Leaf).

The resistors used for cable identification by the EVSE do have a limited number of steps specified in the standards - probably too crude to be very useful for solar charging, but in theory available on any socketed EVSE.

The resistors used by Mainpine on their controllers are a proprietary design feature by Mainpine so they can in principle do anything they like in their software, though apparently limited to a modest number of steps in current versions.
I had thought the resistor might be the way to determine charging rates but now I'm wondering if the frequency of the square wave is what determines it.(or as someone suggested some form of modulation on that square wave) From what I've read, the EVSE equipment outputs this square wave as was said here too. So here's my theory. If you only have a 3.3kW unit, the square wave will reflect this and the car will only take 3.3kW. On the other hand, if you have a 6.6kW unit, the signal from the EVSE will tell the car that it's in a position to deliver 6.6kW and then leave it to the car to decide if it can take it or not. As far as I can make out, the EVSE has a contactor within so it just directly connects the live and neutral of the cable and therefore the socket of the car. The car then determines what it will take and based on the signal from the EVSE, it will not take so much that it will burn out the EVSE.

Following from this theory. The granny charger I have charges at 10A or about 2.4kW. If my theory is right, a different frequency on the control pin tells the car that the granny charger can deliver 2.4kW and so the car only takes this.

If there are resistors knocking around, I wonder if these are to determine the power capacity of the connecting cable. Some cables are claiming a power capacity of 3.3kW; others are 6.6kW. But if you connect a 6.6kW untethered EVSE to a 6.6kW charging capacity car with a 3.3kW rated interconnecting cable what will happen (what will set the current limit?)

This is just a theory. I must get out the oscilloscope. But if it was true, then a variable frequency could be used to match power production from the panels to power taken by the car.
 

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I had thought the resistor might be the way to determine charging rates but now I'm wondering if the frequency of the square wave is what determines it.(or as someone suggested some form of modulation on that square wave) From what I've read, the EVSE equipment outputs this square wave as was said here too. So here's my theory. If you only have a 3.3kW unit, the square wave will reflect this and the car will only take 3.3kW. On the other hand, if you have a 6.6kW unit, the signal from the EVSE will tell the car that it's in a position to deliver 6.6kW and then leave it to the car to decide if it can take it or not. As far as I can make out, the EVSE has a contactor within so it just directly connects the live and neutral of the cable and therefore the socket of the car. The car then determines what it will take and based on the signal from the EVSE, it will not take so much that it will burn out the EVSE.
It is the mark/space ratio of the square wave (at constant 1kHz frequency) that specifies the available current.

Common EVSE in the UK are 16A, 30A or 32A, so don't exactly match the two models of Leaf - as you say, the signal from the EVSE specifies the maximum and the car draws some current less than or equal to that, based on its own capabilities and needs.

Following from this theory. The granny charger I have charges at 10A or about 2.4kW. If my theory is right, a different frequency on the control pin tells the car that the granny charger can deliver 2.4kW and so the car only takes this.
Different mark/space ratio, but yes the granny lead specifies 10A and the car takes some current less than or equal to that.

If there are resistors knocking around, I wonder if these are to determine the power capacity of the connecting cable. Some cables are claiming a power capacity of 3.3kW; others are 6.6kW. But if you connect a 6.6kW untethered EVSE to a 6.6kW charging capacity car with a 3.3kW rated interconnecting cable what will happen (what will set the current limit?)
With an untethered (detachable cable) EVSE, the resistor in the cable tells the EVSE the capability of the cable, and if the EVSE's capability is greater than that of the cable, it reduces the current signalled on the square wave to match the capability of the cable.

These cable resistors are less useful for your solar charging purposes: there are only a small number of values defined, in fairly large steps. Also, the EVSE isn't obliged to read the value other than at the start of charge, because it locks in the cable and is entitled to assume you haven't changed it.

Some models of EVSE have proprietary resistors internally to set the maximum rate - these may or may not be useful to your purposes, depending on the EVSE manufacturer.

This is just a theory. I must get out the oscilloscope. But if it was true, then a variable frequency could be used to match power production from the panels to power taken by the car.
It's more than a theory - this is definitely how it works (I have some of the standards documents). The mark/space ratio can be adjusted to match the car's consumption to solar production, but:
  • The minimum value that can be specified with the square wave is 6A. This gives you a problem on cloudy days (unless you have a huge solar installation).
  • The car isn't obliged to follow the EVSE's current precisely, just to never exceed it. So the car may work in granular steps and/or be slow to turn the power back up again after you've turned it down. However, most cars seem to implement it in a reasonably useful fashion.
  • You can do this for fun, but when you work out the financial savings they really aren't enough to pay for any more than trivial spending on gear to achieve the solar following.
  • Charging at low currents is, for most cars, significantly less efficient than charging somewhere closer to full power. So you can optimise for cost, but that's not necessarily the 'best' thing to do from a 'green' point of view.
 

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Thanks arg for the comprehensive reply.

The fact is that at the moment, there is no feed in tariff for Domestic Renewable Energy in the Republic of Ireland. In fact, unless I get the meter changed to an in / out meter, I will be charged for uploading any excess power to the grid. There is a solution available which monitors the current in the connection to the grid and controls the consumption in an immersion dump load to balance the power consumed by the house with the power generated by the panels. Clever, but I'm thinking why not direct this power to the car. So, the plan would be to break the control signal from the EVSE and replace with my manufactured signal and balance the generation and household demand by feeding the excess into the car. The 6A minimum current is another bit of a stumbling block.

Anyway, it might never happen!
 

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To OP. Plug it in and if it takes hours to charge its a 6.6, if it takes hours and hours and hours its a 3.3kw. Simple.... the end.
 
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The charge times on dash are not an accurate way to know if you have 6.6 charging capabilities. You have to get a look at the sticker to be sure if it is 6.6 or not. My 2015 dash display shows both 3.3 and 6.6 charge times but the sticker says 3.6.
 

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The charge times on dash are not an accurate way to know if you have 6.6 charging capabilities. You have to get a look at the sticker to be sure if it is 6.6 or not. My 2015 dash display shows both 3.3 and 6.6 charge times but the sticker says 3.6.
Does it charge at 6.6kW?

FIrst time I've heard about a car coded for 6.6 that only has the 3.6 charger.
 

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Can I ask another rather stupid question on this thread which perhaps someone can clarify? The posts on here discussing the various single or dual timers shown on the dash display refer to when the car is plugged in. Can someone confirm whether this is the same when the car is not plugged in?

So if I am sitting in a Leaf (no charging cable connected) and I switch on the Start button and flick through to the charge completion screen, what would I expect to see in a 3.3kw versus a 6.6kw?

Would the 6.6kw show two charge completion times even when not plugged in?
 

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The charge times on dash are not an accurate way to know if you have 6.6 charging capabilities. You have to get a look at the sticker to be sure if it is 6.6 or not. My 2015 dash display shows both 3.3 and 6.6 charge times but the sticker says 3.6.
Could this be a car which has had the charger changed? I cannot imagine the factory making such a mistake. Kerry has made one post then vanished. Was "she" a troll?

Before you say it, yes I know it was months ago.
 
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