Fuse Board to Consumer Unit?

ericmark said:

Lighting does not tend to have earth leakage so no real need to put on it's own RCBO.

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Are you talking about not RCD/RCBO-protecting the light circuit at all? If not, the problem with "not putting it on is own RCBO" would be another way of saying "put it on an RCD shared by other circuits" - and those "other circuits" could then trip the RCD, taking out the lighting circuit.

Kind Regards, John

No I am saying that lights are unlikely to trip a RCD. We have prime candidates for tripping a RCD. Any item with a mineral insulated heater, these tend to absorb moisture be it cooker, washing machine, tumble drier or immersion heater although the latter seems less prone to absorbing moisture from end seals they normally go from overheating either lack of water or build up of lime. We also have EMC filters these also tend to cause leakage.

So we want to separate items likely to cause tripping from items unlikely to cause tripping. We can put all items unlikely to cause tripping on their own RCD so these items will not be affected by the prime candidates for tripping.

This does however leave us with one problem. Lights would all end up on the same RCD so should it trip unless emergency lights fitted we lose all lights. But to my mind even if we split lights to two RCD's we still have the same problem as each room is only supplied by one lighting RCD the only way we stop a single RCD from plunging us into darkness is to use some lamp plugged into a socket so putting cooker, and sockets on one RCD and lights on another would still give two supplies to each room.

Having all sockets on same RCD means there is no way to by simple substitution working out which item is faulty. So to my mind we need at least three RCD's in a house. Putting lights on a RCBO seems the easy way out. It is as I have said before a risk assessment and it does not really matter if the RCBO feed sockets or lights as long as lights not on same RCD as sockets and there are two RCD's feeding sockets even if second RCD only feeds socket on cooker supply it means one can as a temporary test move items like fridge/freezer to another RCD to work out what is causing a trip.

Over three RCD's one has a problem knowing a RCD has tripped. If for example the fridge/freezer was on it's own RCBO the question arises how long would it take for the occupier to realise it has tripped? My freezer and fridge/freezer show little blue icons when powered but only because of the settings selected if I did not select Eco then one would need to open door to see if powered up. With older fridge/freezer and freezer there was nothing and even opening freezer door did not show if powered or not. I have sat here writing on Lap top and cursed slow internet when in fact the power to router had tripped. Just happens on different RCD with main RCD the landing light comes on as emergency type and that for use is often the alarm that power has failed. Some people seem to have house alarm set to warn them at least with general power failures I always seem to hear alarms go off. Thought they would be battery backs but from noise when power fails clearly not only bell battery seems to work!

So again I say it's a risk assessment and clearly will vary house to house. This is something to me the home owner should work out it should not be left to the electrician.

Just an update, second fix of rewire now complete... metal-clad Consumer Unit now doing its thing. Also, some of the gubbins shown in the first picture of this thread are ancient and belong to the YEB (now Northern Powergrid) and it has taken them around 7 weeks to agree they'll remove it, free of charge. Electrician couldn't legally touch some of it, apparently.

Things progress...

dpm_dpmartin said:

Also, some of the gubbins shown in the first picture of this thread are ancient and belong to the YEB (now Northern Powergrid) and it has taken them around 7 weeks to agree they'll remove it, free of charge. Electrician couldn't legally touch some of it, apparently.

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In the "old" days, everything up to and including the meter was the property of the relevant electricity board. Now with the split responsibility for providing supply to a property and for metering/billing usage, the incoming feed up to and including the cutout belongs to the DNO, and the meter to whoever you are paying for electricity. So even though the property might have a new supply and meter outside, that old feed and cutout are still the property of the DNO.

Northern Powergrid eventually sent someone (another company actually) around and they removed the old gubbins from the cellar, which was nice. They'd spent around 6 or 7 weeks trying to persuade me it was the meter... massive thick wires into the two houses on either side are also gone. Happy days.

Good news that its sorted.