Plastic versas Metal CU's - your chance to vote

[Octopus]

Pretty much as the title says - lots of us have opinions but seeing as BEAMA seem to have ruled out plastic CU's lets have a poll - so please add your vote:

 

[frontier219]

This 2 screw terminal business....agree. Problems occurred because of change over to mcb's, which only have the one terminal screw, a different type altogether.

'Oh, well we might as well make N and E a row of single screw terms on a sliver of brass ' save a chunk on production cost.....and who even mentioned it at the time?

Yep. Double terminal screws and fixed busbars would sort the issue much better than metal CUs IMO.

 

[Leesparkykent]

Have you seen these in city's? I know it's only the main switch with twin screws but it's a start in the correct direction. Also the circular terminal is better IMO.

 

[Octopus]

If the muppets at BEAMA actually wanted to improve standards they would make the main switch as above compulsory NOW.


Like it!

 

[ipf]

Yep. Double terminal screws and fixed busbars would sort the issue much better than metal CUs IMO.

mmmm....but, then again, use a correct torque screwdriver and the problem's solved anyway.......my giddy aunt tells me.

 

[frontier219]

mmmm....but, then again, use a correct torque screwdriver and the problem's solved anyway.......my giddy aunt tells me.

I still believe the main problem is sparks in a rush getting the busbar in behind the screw, rather than it not being tightened properly, hence fixed busbars being better.

 

[ipf]

If the muppets at BEAMA actually wanted to improve standards they would make the main switch as above compulsory NOW.


Like it!

Yes. Quite interesting is that. Surprised City are involved , though.

 

[Octopus]

I'm still awaiting a response from Keith Smith at BEAMA to the following email I sent him:

"Keith

I appreciate your candid response and openness.

The quality of fuseboards has progressively dropped over the last 20 years and now they are so flimsy, and I'm not just referring to the, completely flimsy cases, it's the quality of the main switches, the mounting bars, the MCB's the RCBO's - this is what needs fixing.

Introduce a requirement for main switches to have 2 screws per terminal would be a step in the right direction and that coupled with improving the "strength" of the busbar for the MCB's and RCBO's would be good too.

My point remains that you can improve the case BUT ignoring the internal components and in some cases dangerous workmanship is not dealing with the problem."

 

[ipf]

I still believe the main problem is sparks in a rush getting the busbar in behind the screw, rather than it not being tightened properly, hence fixed busbars being better.

Not the point I'm making.....it's all in the 'industry' of making money. Who the hell worth his salt needs to apply torque settings to correctly connect a terminal. One thing leads to another and it's not 'the blind leading the blind'....it's those with their eyes wide open.

 

[Leesparkykent]

Could incorporate strain relief for the tails, like the one in the pic or have it nearer the bottom entry on the DB where the tails enter.

 

[telectrix]

the main problem, IMO, is the fact that main switches and RCDs will only accomodate a very short length od conductor in the terminal. anything over 1/4" leaves copper showing. having 2 screws and at least 1/2" of copper in the terminal will cure 75% of the problem.

 

[richy3333]

the main problem, IMO, is the fact that main switches and RCDs will only accomodate a very short length od conductor in the terminal. anything over 1/4" leaves copper showing. having 2 screws and at least 1/2" of copper in the terminal will cure 75% of the problem.

And that's scientifically proven (in 73.67% of cases )

 

[Knobhead]

Have you seen these in city's? I know it's only the main switch with twin screws but it's a start in the correct direction. Also the circular terminal is better IMO.

Funny how things turn full circle given time.

 

[Lee Marshall]

I think main switches should have two screws per terminal like in meters. Loose connections are how most fires start so why not think about how to stop a fire starting rather than how to stop it spreading?

 

[telectrix]

I think main switches should have two screws per terminal like in meters. Loose connections are how most fires start so why not think about how to stop a fire starting rather than how to stop it spreading?

far too simple a solution for IET. why use common sense when a load of ambiguous waffle generates income?

 

[UNG]

Why is it the electrical industry seems to be more prone to knee jerk reaction changes from the powers that be without any analysis of the information presented to them, LFB has spoken and the IET has jumped in feet first

At the stroke of an amendment are all those CU's that have been installed on the back of the 17th edition now non compliant and will they have to be replaced:biggrin::biggrin:. I sense another load of customers getting stung again

 

[Knobhead]

At the stroke of an amendment are all those CU's that have been installed on the back of the 17th edition now non compliant and will they have to be replaced:biggrin::biggrin:. I sense another load of customers getting stung again

You’ve only got to read some of the threads on here to see that some of the unscrupulous so called “electricians” will be using this as an opportunity to fleece customers.

 

[7029 dave]

What many don't realise with these type of modular connections,is that you need to flatten out the conductors, if left uniform it will not bite down on the whole conductor, and just fall out with not too much force.

 

[GB.Kayak]

Why is it the electrical industry seems to be more prone to knee jerk reaction changes from the powers that be without any analysis of the information presented to them, LFB has spoken and the IET has jumped in feet first

At the stroke of an amendment are all those CU's that have been installed on the back of the 17th edition now non compliant and will they have to be replaced:biggrin::biggrin:. I sense another load of customers getting stung again

You’ve only got to read some of the threads on here to see that some of the unscrupulous so called “electricians” will be using this as an opportunity to fleece customers.

If the installation is otherwise sound, particularly on the basis of all in-CU connections, then the non-retrospective nature of BS 7671 should not make this necessary. That said ... all customers should be presented with an unbiased summary of the risks that their electrical installation presents. I agree with your point, we have all seen the way that the unscrupulous present the 'evidence' and press customers to take action that is in the dealers' and not necessarily the customers best interest! I am, like others, also concerned of the potential impact of a fault that I have missed becoming an incident that injures or maims. If it could be argued that a metal CU may have reduced the severity of the incident or eliminated the incident altogether, how do I demonstrate in court that I have discharged my duties as a professional?

 

[Silly Sausage]

You’ve only got to read some of the threads on here to see that some of the unscrupulous so called “electricians” will be using this as an opportunity to fleece customers.

Well, the in-service stock of 3036 Wylexes is probably starting to run a bit low these days.

 

[Knobhead]

You’ve only got to read some of the threads on here to see that some of the unscrupulous so called “electricians” will be using this as an opportunity to fleece customers.

The annoying thing is that I felt the need to make a comment like that. Unfortunately we all know it is a true statement of fact.

 

[Engineer54]

Funny how things turn full circle given time.

That Wylex CU in all it's different configurations was revolutionary when they first hit the market in the early 50's!!

I'd like to see what happens to the frame when tested with this 960'C test wire, because i've tried to burn this treated and matured hardwood frame in the past.... Unless this wood was in constant contact with the red hot burning embers on the fire, there was no chance, and even then was reluctant to continue burning, preferring to glow and carbonise than to burst into flames!!!

 

[GB.Kayak]

That Wylex CU in all it's different configurations was revolutionary when they first hit the market in the early 50's!!

I'd like to see what happens to the frame when tested with this 960'C test wire, because i've tried to burn this treated and matured hardwood frame in the past.... Unless this wood was in constant contact with the red hot burning embers on the fire, there was no chance, and even then was reluctant to continue burning, preferring to glow and carbonise than to burst into flames!!!

I do not know the test setup for the glow wire test ... but if the wire were only held at one end I expect it might bend. Testing modern plastic enclosures @ 960°C must be like putting a hot knife through butter!

 

[Engineer54]

I do not know the test setup for the glow wire test ... but if the wire were only held at one end I expect it might bend. Testing modern plastic enclosures @ 960°C must be like putting a hot knife through butter!

So Maybe those old wood frame Wylex boards could still pass the Amd 3 tests then... lol!! The internals and the original covers were made of a bakelite material, so they would definitely stand up to the 960'C Glow Wire test....

 

[SPARTYKUS]

That Wylex CU in all it's different configurations was revolutionary when they first hit the market in the early 50's!!

I'd like to see what happens to the frame when tested with this 960'C test wire, because i've tried to burn this treated and matured hardwood frame in the past.... Unless this wood was in constant contact with the red hot burning embers on the fire, there was no chance, and even then was reluctant to continue burning, preferring to glow and carbonise than to burst into flames!!!

Ha. Wouldn't that be ironic if it did pass.

 

[Engineer54]

Ha. Wouldn't that be ironic if it did pass.

I'm thinking the only place where it would fail (relating to the Amd -3 enclosure requirements) is it being an open back design, ...but then if the material it was mounted to was also proven to be non combustible, ...then maybe!! lol!!

 

[GB.Kayak]

So Maybe those old wood frame Wylex boards could still pass the Amd 3 tests then... lol!! The internals and the original covers were made of a bakelite material, so they would definitely stand up to the 960'C Glow Wire test....

It would not surprise me if they did via the non-combustible route according to the test criteria that Damien published. Therefore another example of 'non-combustible' according to the relevant standard. I find it hard to believe that a 'glowing wire' can concentrate sufficient energy at its tip or even along its length to ignite solid timber.

 

[Knobhead]

Ha. Wouldn't that be ironic if it did pass.

It would,

I’ve been doing some digging around about phenolic plastics and the 960°C hot wire tests.

Like E54 I’ve tried to burn the Wylex wooden frame. Plain and simply it just doesn’t burn.

 

[Knobhead]

It would not surprise me if they did via the non-combustible route according to the test criteria that Damien published. Therefore another example of 'non-combustible' according to the relevant standard. I find it hard to believe that a 'glowing wire' can concentrate sufficient energy at its tip or even along its length to ignite solid timber.

The 960°C test is three turns of nichrome wire wrapped around the test piece. The rest I’d have to look up regarding time, wire spacing and test piece size.

 

[SPARTYKUS]

Excellent.

yes I am not sure about Bakelite and when you can safely assume it will ignite or is damaged by heat. It being a thermoset and all.

 

[GB.Kayak]

The 960°C test is three turns of nichrome wire wrapped around the test piece. The rest I’d have to look up regarding time, wire spacing and test piece size.

Anyone got a spare example and know of a 'friendly' accredited test organisation?