Depends on your definition of "safe". If it trips in the middle of the night you are left with no power and no light. Of course you should have a torch but have recently had a hard trip due to water ingress on my split board which persisted even though the MCB was off, I would suggest this could be very very inconvenient...
Dave
In houses with a whole house RCD (except for TT systems), the lights would not have been put under the RCD protection.
Later, dual-RCD, installations should have had the lights on the opposite RCD to the sockets for each floor, so tripping of the lights on one floor would still allow a table lamp, TV or suchlike to give some light.
No, with a whole house RCD, there is just the one master switch ie the RCD
- everything is on it,
Err, not necessarily. Parents house was built in 1956 on land to the side of the bungalow where we lived.
Lighting circuits had no cpc, so when my step mother decided that the original 'Shell' wall lights 'had' to be replaced with horrid metal replacements the electrician correctly added a whole house RCD to the existing old-fashioned fuse board. This was not a problem until they started using Tesco bulbs instead of decent quality Osram or whatever and were occasionally plunged into darkness when a bulb blew.
Nothing wrong with whole house RCD - better than no RCD.
Obviously the bastards trip too often and RCBOs are better.
They were. It was whole house.
Mine still is, though it has a 100mA trip in it. I must put RCBOs in before I die.
Its a matter of choice. Certainly modern practice is one for every outside socket. Personally if they fitted the CU and I had the time and the money it would be one per ring or spur for me.
In an ideal world yes.
What would be the alternative?
Can you imagine the outcry if every time a new revision of the wiring regs (or a new amendment to the current one) was released, every property owner was supposed to bring their properties up to the new standard?
The current scheme for requiring new work to be done to current standards is a much more workable policy, and with time achieves much the same result.
They commonly were... there was a time when adding a new enclosure containing a RCD before the existing CU was quite a common practice.
For 17th edition installs on, the minimum would be two - with all circuits spread between them.
However the price of RCBOs has come down dramatically, so it is entirely reasonable to using one on most circuits, and largely do away with "shared" RCDs.
Some division on the "everything else" would probably be sensible - so lights and sockets on one floor are powered from different RCDs. That way you always have the option of light on each floor (even if it has to be via a plug in lamp)
Most only covered a subset of the MCBs, with lighting, house alarms and, sometimes, dedicated freezer supplies not covered by the RCD.
No. Always it was the main breaker for all the incoming electrons. By the 80s anyway
What system are you on? 100mA RCD for TT systems are normal. They may also be fitted for Non-TT system, but are usually not and not normally a requirement.
In either case, when 30mA RCDs began to be used as well, for protection of life, they usually only covered circuits other than lighting (hence the use of split-load consumer units, with a single RCD), until dual RCD boards became the norm.
IIRC the 16th edition regulations required a single RCD, covering sockets likely to be used for powering equipment outside, which was gradually considered to be most sockets. Often, everything but the lights (certainly all the sockets) was covered by the RCD and it was considered a whole house RCD. Mine had lights and alarm unprotected.
17th required twin RCDs, with everything split between them and lighting on the opposite RCD to the sockets in that area. 18th edition hasn't really changed that although there has been more emphasis in guidance on not tripping multiple circuits and so a general move towards RCBOs.I suppose as prices come down, there will be a shift from RCBOs to AFDDs
- which are already required in some circumatances.
Extra protection could be provided, but for 16th edition installations, the norm was a consumer unit with a single RCD, required only to cover sockets likely to be used to supply equipment outdoors - although it often covered all sockets. The CUs were generally split-load, with lighting on the non-RCD side. Even new installations were generally like that.
I have gone that route, but only after a) Crabtree introduced miniature RCBOs that are exactly the same dimensions as their MCBs (previously they were the same width, but much taller and my box would not fit the old ones) and b) the price dropped to a sensible level.
I had to change the busbar to a non-split load one. The extra space from ditching the RCD allowed me to add an SPD and added a couple of spare spaces for future use (one now used for an EV charger).
It has solved the random trips that were due to too much leakage from numerous filters on devices around the house.
Surely in the '80s and '90s, the norm was for the supply to go straight from the meter to the CU main switch and to have a split load busbar, with RCD protection for part of it? Using an RCD instead of a main switch only came in later? Likely with dual RCB CUs.
In time yes, but possibly killing several people on the way.themselves on the way. Having watch two friends with mild dementia attempt recently attempt to electrocute themselves, on different occasions and in different ways, which was possible because they still had systems with no RCD and conventional fuses.
My next door neighbour attempted to clean a plugged in hair dryer with a nail file. Not sure how she escaped electrocution, perhaps she shorted live to earth or neutral and it took the fuse out, but she was shaking and admitted she had had a nasty belt.
Another put a 13am plug rotated 180 degrees and was then about to poke things into the now open slots when I stopped him....
The current policy and part-P both discourage upgrades. Many people don't upgrade because you either stay on the old system, or you move to the latest level. There is no in-between. In both the above cases the people were elderly and stuck with their old systems because they didn't want the disruption a proper upgrade would cause.
Part-P again discourages upgrades because it then becomes notifiable and folks don't want the hassle of that....
Dave
F*ck knows. They ran a coax cable from the big transformer in the garden and said use that as earth, but I already had a big copper stake so I used that as well
Id go full RCBO if money and space permitted
So what ?. There are plenty of other ways that they will find to kill or hurt themselves.
Darwinism.
Not possible with flush mounted socket outlets
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