13 or 16 amp?

Tex · Mar 25, 2015

For a charge point at work I have the option of connecting to either a 13amp socket or to use a 16amp circuit. Are there advantages in installibg a socket into the 16amp circuit and if so what is best socket type to use?

maby · Mar 25, 2015

There's no benefit in plugging the charger supplied with the car into a 16A circuit if that is what you are suggesting. The car can draw 16A and charge a lot more quickly - but only through a purpose built charging point installed at your house - the supplied charge controller will never draw more than about 10A no matter what kind of socket you plug it into.

Tex · Mar 25, 2015

I was wondering if I could use a different cable than that supplied and connect to the 16amp circuit without a purpose built charge point?

aitchjaybee · Mar 25, 2015

no, you need a control unit. On the supplied cable, its the black box 10cm from the plug. In your home charger, its in the wall unit.

Whilst you may technically be able to make it work without a control unit (I dont know but i guess its possible), the associated potential problems over overcharging and so on would make this a helluva risk for not much gain - unless work provides the cable, a 16A socket as a UK 3-pin would need a custom made cable to have UK 3-pin one end and J1772 the other to fit in the car port.

The 13A actually charges at 10A, but even so, the difference between a 10A charge and 16A from empty is 5hrs versus 3hrs.
the only other benefit is when pre-heating or aircon, 16A can just about keep pace with current draw, whereas the 10A falls a bit behind using up a wee bit of battery.

At work we have a line of 5 13A sockets but most of us arrive early and depart late and have all day to charge.

hope that helps
HJB

Tex · Mar 25, 2015

Many thanks for the prompt and helpful replies.
Just a pity there are no grants for business chargers.

maby · Mar 25, 2015

The electronics in a charge controller is not complex and is well documented, so I guess you could easily build one if you wanted. It does not actually control the level of charge in the battery - that is done by the electronics in the car. The external controller informs the car what the maximum available charge current is and provides the circuit breaker functionality to protect the user from electrocution in the event of a failure. It also tells the car that there is a cable connected and stops the driver moving off and ripping the control box off the wall.