Speak EV - Electric Car Forums banner

1 - 14 of 14 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
Hi, does anyone know what the benefits are of having a variable plug in charger rather than a 13A fixed speed charger? Do you save on electricity costs when charging at 6A?
 

·
Registered
Joined
·
1,132 Posts
Most 'standard' plug in charging leads are actually 10A. The "13A plug" on the end is just the highest rating that such a plug could take.

I bought one that is adjustable to use anything between 6A & 13A. Using the lowest setting when the sun is shining might mean that I can charge for nothing whereas a 10A charge might leave me importing some power. Using the highest setting might mean I'd get more charging done during an off-peak period (though if at home I'd be using the 32A dedicated charging pint of course).

Other than those sort of examples, there wouldn't really be a "saving on electricity costs" by using a lower amperage - you'd just have to charge longer to get the same power supplied.
 

·
Registered
Joined
·
1,955 Posts
The usual granny lead is 10A, some have a switch on the case to take them back to 6A. All granny leads can be stepped down by the car if it has the option in its menus (the MY13 Ampera does for example), its part of the charging specifications, though 6A is the lowest allowed.

There are some chargers which use a Commando plug so can supply upto 30A on single phase with options to cut back the supplied power.

For the UK 3pin plug, 10Amp (2.4kW) continuous for hours on end can damage the plug and wall socket if the socket and wiring is not in tip top condition, it overheats, see various threads on this forum about damaged/ melted plug sockets. Switching down to 6A can alleviate this problem.
The other use for a lower current draw is if you have Solar, this allows charging at 1.5kW so even a moderate setup can fill the car..

Its recommended to get a proper wall box fitted which should give many years of trouble free service. These are designed to provide 30A (7kW) continuously for hours on end so charge the car faster and safer.

Cost is per kWh not by amperage
 

·
Registered
Joined
·
4,847 Posts
you'd just have to charge longer to get the same power supplied.
Which may well mean you use more power as parasitic losses such as car systems will be active whatever the rate.

Hi, does anyone know what the benefits are of having a variable plug in charger rather than a 13A fixed speed charger? Do you save on electricity costs when charging at 6A?
The benefits are really only being able to make use of a limited supply (one that can't comfortably give 10A).
Solar as EricM describes or if forced to use an extension lead or other bodge are the obvious ones.
 

·
Registered
Joined
·
927 Posts
I've got a theory that charging at 6A is kinder to the battery. Though less kind to your electricity bill, as it's less efficient.
 

·
Registered
Ioniq 38kWh
Joined
·
531 Posts
My Ioniq granny has 3 settings, 6, 8 and 10A. I find the 6A very useful for solar charging as mentioned in an earlier post.
 

·
Registered
Joined
·
8,106 Posts
As has already been said... most granny leads charge at 10A or less... but there is at least one that I have come across that does actually charge at 13A. I was at an event where a Peugeot E-208 was charging using the lead supplied with the car and the plug melted! It is never a good idea to charge an EV at 13A on a granny lead and a standard UK socket!
 

·
Registered
Joined
·
1,147 Posts
The current levels from a granny will make no difference to battery life - it's way down in the weeds compared to rapid charger rates.
The main reason that some GCs allow reduction in current is for when they are used on supplies that can't be reliied on to sustain 10A for whatever reason.
Some cars ( e.g. Zoe) are very inefficient when charging at low currents, so down at 6A you're probably putting hardly anything into the battery!
 

·
Registered
Joined
·
3,696 Posts
My granny EVSE, 13A plug, will do 6,8,10, or 16A! I suspect they didn't change the software from he version with Commando plug on! But you have to select that value after starting a charge. I know my Ampera maxes out at 14A, so I have actually used the 16A setting, and, no, it didn't metl my socket or anything! I checked that carefully!

I use the 6A setting a lot, as I have solar panels and being retired am at home on plenty of sunny days. But this will change, when I get round to solarifying my Rolec...
 

·
Registered
Joined
·
499 Posts
Our Zoe uses about 1A to run everything while charging. So at 6A I'd 'lose' around 17%, or it would take me roughly 20% longer to charge than 'ideal'. At 10A that's 10% or roughly 10% longer. At 32A (7kW) it's around 3%.

No idea how much the PHEV needs to run everything while charging, but it will be in the same order of magnitude.
 

·
Registered
Joined
·
927 Posts
This artcle is focused mainly on laptops. This like chalk and cheese compared with modern EV, where the lithium technology is very very different.
Except manufacturers who use laptop batteries to power cars of course. :)

 
1 - 14 of 14 Posts
Top