Type AC which have been the standard on domestic for years, either FTO or take many times the rating to trip, if you have even the smallest amount of DC circuit leaking back to the device.

PV's and EV chargers are becoming more common, but even a poorly made phone charger, USB socket outlets or plug top DC transformer could cause this.

 

Most of the stuff we plug in now a days is AC>DC, gone are the days of the post war copper shortage and a ring of undersized conductors, designed to power two 1 bar heaters...

26 minutes ago, sixwheeledbeast said:

Type AC which have been the standard on domestic for years, either FTO or take many times the rating to trip, if you have even the smallest amount of DC circuit leaking back to the device.

PV's and EV chargers are becoming more common, but even a poorly made phone charger, USB socket outlets or plug top DC transformer could cause this.

 

Most of the stuff we plug in now a days is AC>DC, gone are the days of the post war copper shortage and a ring of undersized conductors, designed to power two 1 bar heaters...

So you saying type b is better option?

I should add that this first rewire was back in 1995

 

MEM Memera 2000 cu, replacing a 2 circuit brown bakelite type Wylex. Had to get the board out for PME and an upgrade from the ceramic Siemens Brothers 40A cutout.

 

Back before Part P (which of course has now been relaxed not to include outdoors) about a month later, the householder had a pond pump fitted via a garden centre(!) and the idiot tripped the RCD. He couldn't work out the old 'down then up' reset manouvre, so told the owner it was faulty. She got me to finish the job off and I don't think she ever paid for the pump or the bodged installation job at all.

 

I agree all RCBO should be the norm except for specialist circuits.

Edited September 6, 20196 yr by datadiffusion

Type B would be over the top for domestic. A minimum standard needs to be reasonably attainable to be effective.

If cost is not an issue I always install RCBO's as standard on any consumer unit swap out or adding additional circuit