Electric Vehicle Charging Installations

Section 722: Electric Vehicle Charging Installations was originally added to BS7671 as Amendment 2 in 2013 as a loose copy that could be ‘stuck’ into the book. It was incorporated into the full version of the 17th Edition Wiring Regulations with Amendment 3 in 2015.

It’s intended to cover the supply to electric vehicles charging at above 10A and does not cover induction charging.

Things to note…

722.411.4.1: No PME earthing where the charging point or the vehicle are located outdoors except for either…
(i) A 3 phase installation where due to the characteristics of the load conditions in the event of  a break of the incoming PEN conductor the voltage between the main earth terminal and the earth does not exceed 70 V.
(ii) The main earth terminal is connected to a an earth electrode and again in the event of  a break of the incoming PEN conductor the voltage between the main earth terminal and the earth does not exceed 70 V.
(iii) When protection is provided by a device which disconnects the live conductors of the supply and earth within 5 seconds in the event of the voltage between the circuit protective conductor and earth exceeding 70 V.

However the requirement of the above regulation need not apply for the charging point in a dwelling if (i), (ii) or (iii) are not ‘reasonably practicable’. Point (ii) could be used through the use of a low resistance earth electrode.

For more information there is an IET publication: Code of Practice for Electric Vehicle Charging Equipment Installation 

 

 

 

 

 

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