Blog
7 Feb 2024
The short answer is there isn’t one, however….
There are many factors to consider when answering this question. As a general rule of thumb cables should always be as short as possible, you should choose a cable length that suits your situation, that reaches your car, without too much excess. Too short and you risk putting excess stress on the charging station and charging input on your EV. Too long and they become a trip hazard and difficult to tidy away.
Electrical resistance within copper cables increases with length, which causes voltage drop. To mitigate this you increase the cross sectional size of the conductor. At ViperEV we have successfully tested EV charging cables at 100m, with the charging station and vehicle communicating without issue. We only use high quality copper in our charging cables, and all the cables in our ‘Flex’ range have 6mm conductors. However running our cables at 7.4kw (32amps @ 230v) at a length of 100m, you can expect a voltage drop of around 25v (10.9%). Which is outside the permissible range of 5% set out in UK regulations. When making these calculations you also need to consider the additional length of cable from your consumer unit to your EV charging station.
If you would like to run a domestic charging station at its full potential of 7.4kw (32amps @ 230v), the longest length of cable you can use is 45m, the length of cable from your Consumer Unit to Charging Station should also be factored into this calculation. We have various solutions if your situation demands a longer length. Please contact us to discuss how we can help you.
