16 amp commando sockets. 20 amp mcb on site guide as maximum value mcb

[David Rann]

Hello the on site guide lists 20 amp maximum mcb for 16 amps sockets. Having a debate with someone as to why this is? Why not 16amp mcb? I installed 20 amp mcb as it's for a car charger that charger's at 16amps for 8 hours and is not capable of pulling more than 16 amps but this has been pulled as a C2. I didn't install 16amp as have in the past and over time the bi metallic strip has worn and started to trip after 12 months or so.

Cheers

 

[westward10]

I wouldn't Code it at all but if a 16A device trips then it is inadequate for the connected load and this must also apply to the 16A socket, change it to a 32A socket.

 

[David Rann]

Can't change it to a 32amp as it's a fixed adapter with electronics inside.

 

[telectrix]

if the charger is designed to plug into a 16A socket, then the 16A socket is sufficient.

going by the argument of whoever coded it, that means we need to fit 13A socket circuits with a 13A MCB.

 

[Simlec]

20 amp should be fine supplying your 16amp socket as you say its covered in OSG part H3.
Out of interest have you hit mainly drains installing your earth rods for your EV chargers ?

 

[David Rann]

20 amp should be fine supplying your 16amp socket as you say its covered in OSG part H3.
Out of interest have you hit mainly drains installing your earth rods for your EV chargers ?

I don't know! Scary every time though. Bought a cat scanner for cables but still!! 18th edition takes out the "where reasonably practical" bit. So expect a lot of People hitting utilities

 

[David Rann]

16 amp commando and the osg.

 

[Simlec]

lol, I was expecting to see lots of pic's online of earth rod explosions and like but nothing yet (that I have seen) but I feel its coming.

 

[David Rann]

lol, I was expecting to see lots of pic's online of earth rod explosions and like but nothing yet (that I have seen) but I feel its coming.

I need to make sure my public liability covers it!

 

[davesparks]

Because it's an ev charger and like I said in the original post charges for 16 amps constant. Over time I have had them wear the bi metallic strip and start to trip. 20 amps takes the stress off and complies with IET on site guide.

This suggests it is either a poor choice of MCB or actually pulling more than 16A.

A single 16A socket shouldn't need to have an ocpd of more than 16A supplying it, if it does then it is most likely overloaded.

 

[David Rann]

This suggests it is either a poor choice of MCB or actually pulling more than 16A.

A single 16A socket shouldn't need to have an ocpd of more than 16A supplying it, if it does then it is most likely overloaded.

Would you C2 it though?

 

[Ian1981]

Stick a clamp meter on the circuit to see how many amps it's pulling

 

[David Rann]

No point...this is about someone coding a c2 contradicting the IET

 

[Ian1981]

delete

 

[Simlec]

What does he need to clamp it for? He has designed it correctly and no parts are in danger .
No code and I don’t see how you can code it.

 

[Deleted account]

An EICR is only to test and inspect the electrical installation. Not the equipment/ appliances plugged into it. If an appliance is over loading the 16a commando socket then that is an issue with the appliance, not the installation.