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Hi, I'm a newbie about EVs and I'm here to ask for a clarification.
After reading some docs about EVs, I learned that there are 4 different charging modes, where each of them specifies voltage and current values during EV charging (so, indirectly, the absorbed power).

For example, I read that in my country, during a slow charge, if an EV is recharged by a single-phase supply (230 V), it will absorb (at maximum) 16 A (so about 3.7 kW).
"16 A" corresponds to the maximum current rating of my household, so I guess that, during EV charging, it's possible to reduce the current which the EV absorbs, so that it is also possible to use, at the same time, some other electric equipment (such as TVs, appliances, ...) without causing an electric overload.

Is it right?
If yes, how the current (during the charging phase) is reduced? "Manually" or is it done by a specific device?

Is there anyone who could clarify me this? Thank You!
 

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Ampera aka IGOR
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I can only answer for two cars:-
Vauxhall/Opel Ampera using the factory-supplied charging unit the car will default to 6 amps, this can be over-ridden to 10 amps (early cars/charging cables had the controls on the external box, later cars/charging cables had the option within the car on the charging screen menu). The full 16 amp capability can only be supplied with a dedicated supply purely for the EV.
Tesla Model 3 the charging rate can be reduced within the car manually. I'm not sure if this needs to be done every time the car is plugged in or if it will remember it from one charging session to the next at the same location.
 

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If you want automatic charge reduction to load balance with the house load I think you may need a smart charger such as the Zappi or similar. I know my Zappi can do this but as I charge at njght it has not needed to do this yet.
 

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It depends on the car's on-board charger, that dictates the maximum possible AC charge rate. This is typically 7kW for 230v single phase (=32 amps).
In addition, the EVSE (wall charger or portable granny charger) tells the car how much icurrent t's allowed to draw.
This is typically a fixed value between 6 and 16a for a portable unit, sometimes user adjustable, and can also change during charging, for example if the EVSE supports load balancing or solar.
 

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Hi, I'm a newbie about EVs and I'm here to ask for a clarification.
After reading some docs about EVs, I learned that there are 4 different charging modes, where each of them specifies voltage and current values during EV charging (so, indirectly, the absorbed power).

For example, I read that in my country, during a slow charge, if an EV is recharged by a single-phase supply (230 V), it will absorb (at maximum) 16 A (so about 3.7 kW).
"16 A" corresponds to the maximum current rating of my household, so I guess that, during EV charging, it's possible to reduce the current which the EV absorbs, so that it is also possible to use, at the same time, some other electric equipment (such as TVs, appliances, ...) without causing an electric overload.

Is it right?
If yes, how the current (during the charging phase) is reduced? "Manually" or is it done by a specific device?

Is there anyone who could clarify me this? Thank You!
Do you have a particular EV in mind.

Does your electrical supplier have any regulations or are they country wide?
 

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For AC charging, the charging system exchanges some signals between the vehicle and the charge point to control the charging process. The charge point provides a signal to the vehicle which indicates the maximum current the vehicle is allowed to draw. Many charge points use this signal in a basic way, to indicate a fixed maximum current that the charge point can support, others do some slightly more sophisticated stuff by varying this maximum current to allow the user to adjust the charge rate, or control it automatically for demand management or time-of-use type purposes.

Have a look here for a guide:
 

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As above. A lot of charge points (PodPoint and Zappi as examples) can use the signal from a current clamp on say the incomer to the house to control the maximum current provided to the car to keep within an overall limit, so effectively if you specify the overall limit into your house as say 16 Amps and other devices in the house draw say 8 Amps they charge point will reduce the current supplied to the car to keep under the total of 16 Amp (it may not be a matching linear reduction to 8 Amps to keep exactly to 16 Amps, instead it may change to a standard current of 6 Amps making a total of only 14 Amps but at least under the limit).
I know nothing of Irish standards but are you really limited to only 16 Amps in total?
 

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The EVSE (portable or wallbox) sends the car a signal to tell it how much current its allowed to draw. A typical wall box will signal either 16 or 30/32A, and in the UK most portable EVSE's will signal 10A.

The pilot singal used is adjustable from 6A to in excess of 40A.

If you want to adjust it, you simply need an EVSE that lets you adjust the pilot signal.

As mentioned some of the more fancy ones can monitor your supply and set a limit based on that, but many units can have adjustable power levels without those features.
 

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The EVSE (portable or wallbox) sends the car a signal to tell it how much current its allowed to draw. A typical wall box will signal either 16 or 30/32A, and in the UK most portable EVSE's will signal 10A.

The pilot singal used is adjustable from 6A to in excess of 40A.

If you want to adjust it, you simply need an EVSE that lets you adjust the pilot signal.

As mentioned some of the more fancy ones can monitor your supply and set a limit based on that, but many units can have adjustable power levels without those features.
There's some country specific issues that the OP needs to take into account, plus what is he intending to charge, could be a Twizzy or might be a Model S
 

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I have a "granny" EVSE with 13A plug fitted, bought from evconnectors.com . They have a version of this with a Commando plug fitted if you prefer. This can be set to 6,8,10,13,16A offered to the EV. I've just blown one of these up after 5 years hard use, and I suspect that running at 13A generates more heat internally than 6/8/10 do, so reducing the lifetime a bit. It blew up with a short circuit where the mains 13A wire comes into it & a 1/4" connector slides onto the spade soldered to the circuitboard. The base of the spade is where the damage happened. Despite blowing it up, I've replaced it with another the same, as I'll a) treat this a bit more gently & try hard to stick to max 10A!, and b) I'll open it up after a couple of years, check the relays (which wear out) and I'll re-solder those pesky mains terminals inside it.

Another cheap way to get this variable current capability on an existing wall-mounted EVSE is to fit a Viridian Mainpine ECU (brains module) in place of the existing "brains" bit. This is an easy swap on a basic Rolec, e.g. the 16A or 32A ones as sold a few years ago. Their fixed-current ECU simply unclips, pop the Viridian in, ignore the Rolec's LEDs (wrong polarity for Viridian), put a clear plastic window over hole where Rolec LED used to be, and screw a resistor of your own choosing between 2 of the terminals on Viridian. This resistor selects the current offered to the EV, so if you instead wire in a rotary switch with a bank of resistors, you can have a whole range of currents you choose from a knob. Current can be varied while the charge is in process, if you want. If you really want to go to town, you can use a digital resistor (digipot) driven by say an Arduino to set the resistance you want, and at the same time monitor the current the house as a whole is using, using a current-clamp round the house's mains input wire. The Arduino can then compensate for e.g. solar-panel fluctuations due to weather, and even stop the charge completely if you wanted. I'm intending to getting back to implementing this for myself this winter. Got the bits, just haven't integrated them all yet!

Quite a lot of EVSEs have a custom circuitboard doing the "brains" work, so it would be harder to fit this ECU to those. But still do-able by someone happy with electrical circuitry, mains voltages etc.
 

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I know nothing of Irish standards but are you really limited to only 16 Amps in total?
That was my first reaction. 16A is really low for an entire house. Are you sure it's not 60A? My house fuse is 100A, which I believe is pretty common.
16A....boil the kettle while watching TV with the lights on, and you'd be tripping that. Forget the portable heater... :unsure:
 

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That was my first reaction. 16A is really low for an entire house. Are you sure it's not 60A? My house fuse is 100A, which I believe is pretty common.
16A....boil the kettle while watching TV with the lights on, and you'd be tripping that. Forget the portable heater... :unsure:
That's an Italian flag. Not Irish. :)
 

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3kw standard supply capacity in Italy, you can get more if you want it apparently
That's a bit shocking, isn't it?

I believe German houses are routinely fitted with 3 phase power. How nice would that be to have here? :)
 

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That's a bit shocking, isn't it?

I believe German houses are routinely fitted with 3 phase power. How nice would that be to have here? :)
Electricity is very expensive in Italy too so I gather, due to a lack of domestic generation so a lot is imported. Even mobile caravans in Uk usually have a 20amp/32amp supply.
Some but not all EVSE chargers come have the function to cycle between currents, the one on my Ioniq does 6,8 and 10Amp, selected by a button on the back of the unit.
 

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Hi, I'm a newbie about EVs and I'm here to ask for a clarification.
After reading some docs about EVs, I learned that there are 4 different charging modes, where each of them specifies voltage and current values during EV charging (so, indirectly, the absorbed power).

For example, I read that in my country, during a slow charge, if an EV is recharged by a single-phase supply (230 V), it will absorb (at maximum) 16 A (so about 3.7 kW).
"16 A" corresponds to the maximum current rating of my household, so I guess that, during EV charging, it's possible to reduce the current which the EV absorbs, so that it is also possible to use, at the same time, some other electric equipment (such as TVs, appliances, ...) without causing an electric overload.

Is it right?
If yes, how the current (during the charging phase) is reduced? "Manually" or is it done by a specific device?

Is there anyone who could clarify me this? Thank You!
The electronic design of the charger will be optimised to a particular power/current. Follow the guidance, or get a power monitor and run the tests yourself, come back and report your answer.

No two cars need be exactly the same, so there is no 'one' answer. Even the SOC and battery temperature at which you are performing the charge will cause a variance.

Expect an efficiency in the 80 to 90% range.
 
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