New circuit in plastic consumer unit. Yes or no?

[brianmoooore]

I've seen many more 'degraded' steel CUs/switch fuses than I have plastic ones. Holes big enough to put your hand through in some cases.

 

[7029 dave]

I've seen many more 'degraded' steel CUs/switch fuses than I have plastic ones. Holes big enough to put your hand through in some cases.

Yup they get eaten with rust in external boxes.

 

[Dartlec]

One person's engineering judgement may differ from the next and that's fine, as long as the fundamentals are met. It could be an excessive application of 132.16 BUT equally it could be a valid application depending on the points put forward.

Another way to look at is its been considerable time since plastic boards were first allowed (16th? I don't know but I'm guessing close to 20 years?) and plastic does, over time degrade, even on a molecular level, so the drive to change to metal is a valid one (product life expiration).

Some would say its using a sledgehammer to crack a nut but if the end result is a safer installation, is that not the end goal?

Not sure plastic boards were ever 'first allowed' in that sense. Up until the 18th there was nothing in 7671 about the material a CU could be as far as I know.

It may be that there was something that updated in the standard for consumer units/enclosures (now BS EN 61439-3, was 60439, possibly was something else before then) . Some of the standards for main switches etc changed over in about 1991/2 if I recall correctly.

After all the standard 3036 Wylex boards were largely in wood and installed pretty much everywhere well into the 70s and even into 80s maybe in some places.

 

[7029 dave]

The early wylex 3036 CU 4way upwards had 60A dp switch, then changed to 100A later on.

 

[swaRRR]

Would it not be prudent to teach your kids the dangers of sticking a fork in the toaster rather than relying on something that can fail

Kids do lots of stupid things that they know they shouldn't, and sometimes forget and do things by accident that are dangerous.

I see no reason to not install without RCD in a domestic setting. Personally i won't do it.

 

[swaRRR]

One person's engineering judgement may differ from the next and that's fine, as long as the fundamentals are met. It could be an excessive application of 132.16 BUT equally it could be a valid application depending on the points put forward.

Another way to look at is its been considerable time since plastic boards were first allowed (16th? I don't know but I'm guessing close to 20 years?) and plastic does, over time degrade, even on a molecular level, so the drive to change to metal is a valid one (product life expiration).

Some would say its using a sledgehammer to crack a nut but if the end result is a safer installation, is that not the end goal?

By this logic trunking, conduit, MCB's, RCD's, meters, all light switches and sockets, clips, cleats....etc etc, should all be metal.

I'm not convinced metal is inherently safer. On the continent they use plastic and deem it fine. I suspect the change to metal-only is one of those 'we need to change stuff to justify our existence' changes that do little but mean more work gets divvied out in the name of regulation.

 

[pc1966]

Strictly speaking the regs don't demand metal only that it is of a non-combustible material, of which steel is given as an example.

Really it makes sense not to have something that is vulnerable to fire, even if the underlying reason for the fires has often been poor workmanship. More so if the CU has more stuff in it that might cause a significant heat source such as SPD under heavy surge conditions, or transformers or other electronics.

 

[pc1966]

Maybe we can bring back Bakelite ?

 

[7029 dave]

I have never been keen on the modular CU's, practically a skeleton board which you have to build up busbar etc, bound to be more of a fire risk has sweet FA to do with metal or plastic.
Single screws on everything with clamp design (far too much to go wrong), should of stuck with the double screws/solid factory inbuilt busbar.
IMO if they stuck with that concept would be less electrical fires.

 

[westward10]

Maybe we can bring back Bakelite ?

Bakelite has thermosetting properties and you could argue it is compliant to current requirements.