Details of BS7671:2018 Amendment 1 are here.

What do people make of:

 

Protective conductors and exposed-conductive-parts downstream of a protective device provided for the purposes of (iii), (iv) and (v) shall have no connection to:
(a)any protective conductors or exposed-conductive-parts of any circuit not protected by the same protective device; or
(b)any extraneous-conductive-part.

say I have simple independent extraneous-conductive-parts within reach of the charge point or vehicle - say steel sign posts, bollards, crash barriers or fencing. If I can't bond them to the protected/switched PME earth that's connected to the vehicle, that only seems to leave two options - either bond them to the ordinary (unswitched) PME earth (so they'd be hazardous live in a broken PEN situation) or leave them unbonded (with the associated risks of tingles from the EV or charge point under normal conditions or shocks during faults elsewhere on the system) - nether of which seems ideal.


I can see the issue of bonding extraneous-conductive-parts that could have a hazardous potential on them - e.g. metallic pipework that's also bonded elsewhere - as that would defeat the switching of the c.p.c. under broken PEN conditions - but I think there might be two sides to this coin.


   - Andy.

What do people make of:

 

Protective conductors and exposed-conductive-parts downstream of a protective device provided for the purposes of (iii), (iv) and (v) shall have no connection to:
(a)any protective conductors or exposed-conductive-parts of any circuit not protected by the same protective device; or
(b)any extraneous-conductive-part.

say I have simple independent extraneous-conductive-parts within reach of the charge point or vehicle - say steel sign posts, bollards, crash barriers or fencing. If I can't bond them to the protected/switched PME earth that's connected to the vehicle, that only seems to leave two options - either bond them to the ordinary (unswitched) PME earth (so they'd be hazardous live in a broken PEN situation) or leave them unbonded (with the associated risks of tingles from the EV or charge point under normal conditions or shocks during faults elsewhere on the system) - nether of which seems ideal.


I can see the issue of bonding extraneous-conductive-parts that could have a hazardous potential on them - e.g. metallic pipework that's also bonded elsewhere - as that would defeat the switching of the c.p.c. under broken PEN conditions - but I think there might be two sides to this coin.


   - Andy.