Shower Cable - to be 6mm2?

Ooh-err missus!

 

"Mr HA. I am not sure whether you really need an answer or whether you are just being inflammatory but here is an answer. Overcurrent devices are designed to protect the installation and not the users. Under the current regs protection is provided by EEBADS, i.e. bonding, that is supposed to ensure that in the event of a short to a bonded conductive part the overcurrent device will trip. If there is a short to an unbonded conductive part, or to a conductive part for which the bonding has failed, and somebody touches the live part the overcurrent device will not trip. The only device that provides direct protection for the end-user is an RCD (ignoring ELCBs)."





Jolly good answer. I wonder if Ant has read it ?


I also wonder why Ant couldn't answer the question in the first place ?


And Thripster, I know they two are different entities, but my point is(and was),

Would I rather suffer the period before disconnection relying on short-circuit protection(through my body of all things) at full whack,

or,

suffer the period before disconnection(as above)at 30mA at which point a RCD should disconnect.


Yes, I already know which I would rather suffer, but how to make others see that it is a much better option, I don't know!!!!!





Mr. HandyAndy - really

 

but how to make others see that it is a much better option, I don't know!!!!

The best option is neither... which by strange chance is the odds of geting a shock

 

You know, what suprises me, is that there are some people in this forum that beleive an RCD doesn't limit the current, and there are posters that believe it does. Strange how the former hasn't put thier input into this thread.

 

Handy Andy,

The danger due to shock is a function of the product
of duration and current, so, to ask whether 30mA is
safer than 0.4 secs is not really the correct way to
view it.

Regards

 

Where EEBADS is in place and additional RCD protection (as in a split load CU), one could consider an installation 'electrically safe'...


As installed by a 'electrician' who works and sleeps by the regs..


So as long as, no one interferes with such an installation..

Just a thought..

 

Handy Andy,

The danger due to shock is a function of the
product
of duration and current, so, to ask whether 30mA
is
safer than 0.4 secs is not really the correct way
to
view it.

Regards






Yes, and I explained EXACTLY why I asked it, and as yet, you still don't know the answer.

You cannot answer my questions, because you are a fool.

Mr. HandyAndy - really

 

Handy Andy,

The danger due to shock is a function of the
product
of duration and current, so, to ask whether 30mA
is
safer than 0.4 secs is not really the correct
way
to
view it.

Regards






Yes, and I explained EXACTLY why I asked it, and as
yet, you still don't know the answer.

You cannot answer my questions, because you are a
fool.

Mr. HandyAndy - really

SHUT UP

its not as if you are ever going to fit an electric shower is it.

 

Andy, I know the answer, it's you who doesn't understand.

Can we expect someone who doesn't understand what's in that other thread, to understand disconnection times and adiabatic graphs?

 

But where is it that you have given the answer ?


0.4 or 30mA. Which is safer ?



You do not know or you can't say for fear of looking stupid, and agreeing with me.


Mr. HandyAndy - really

 

No, not at all.

Understand the graphs, and think, which comes first. 0.4 or 30mA?

Or is Zs so low and CPC so large to disconnect within 0.1?

That'll get you thinking.

Put it this way, 0.1 or 0.4, there won't be time for a shock!

Did you know, RCD's are also used for 0.4s disconnection? Not just the 30mA cop out.

 

And you still don't answer.

Which is safer ?


And consider also, that the resistance of [my] body mass might mean that o.1 or even 0.4 may not be possible.



Which is safer ? To recieve full power for 0.4 or 30mA til tripped ?


You still don't answer.


Mr. HandyAndy - really

 

I have answered. You just don't get it.

It is inaccurate to ask which is safer.

Tell me, who's going to touch a live part?

Hopefully you.

Don't twist this. This originally was that an RCD is not necessary by BS7671 and you've had to turn it into this.

Do you have your 2381? If not, don't talk it!

 

tripped ?

Which is safer... crashing a blue car or crashing a green car?

Err... neither?

 

How many strands does 6mm have? What size strands are they? Seen a cable today, it had 7 strands and looked like 0.75 cable. Wasn't sure if 6mm or 4mm. It was for a shower.

 

was there no markings on the outer sheath ?

 

Wasn't sure if 6mm or 4mm

A few assorted bootlace ferrules come in handy for such situations...

 

No markings at all. It was a 9.5kw shower. 10mm on a 15 metre run to switch and then this other cable from the switch to the shower. Any ideas? 7 strands at 0.75mm works out at 5.25mm....

 

near enough 6mm then ?

 

suffer the period before disconnection(as above)at 30mA at which point a RCD should disconnect.

Handy
A 30mA RCD doesn't limit the leakage current to 30mA, but will trip, in time, at leakage currents in excess of this.