AFDD and Ring Circuits

[Fleeting]

You are missing first hand experience of seeing an arc tripping a rcd

I am not denying under certain conditions an rcd may disconnect the circuit but rcds do not detect arc faults. If you can contact manufacturers and produce evidence that rcds or rcbos are manufactured to detect arc faults then I will accept your claim.

 

[Sidewinder]

A parallel arc can trip an RCD if it is between the right source and sink.

 

[binky]

If you have two bare conductors with a sterile space separating them then nothing is likely to occur. Introduce a contaminate which produces a marginal conductive path then an arc across them may take place which can be compounded by carbonation of the insulating materials of the conductors.

The only time I've encountered an arc fault and cable burning was on the DC side of a solar array, and that fault was caused by the plumber with a hole saw. That burnt about 6inches if cable before defeating itself. So I'm just trying to get a feel for how often a fault that only an AFDD would detect could occur.

 

[Andy™]

So I'm just trying to get a feel for how often a fault that only an AFDD would detect could occur.

possibly more often than you think

been to plenty faults where theres been a loose connection and the cables have burnt away slightly. whilst nothing bad had happened (other than some flickering lights to no lights etc), an AFDD could well have detected it. however i would also expect some of those faults would have been very hard to find had an AFDD been tripping early on

 

[mort2376]

I know there is a bs standard, however some manufacturers indicators go orange for 1 type of fault and another may turn red no standard for indicating type of fault.

Not an issue for Joe public as you will only have 1 manufacturer in the board, but a nightmare for us.

Hagers rcbos are updateable in the field found that out at the elex show yesterday.