Why would "a bit of bondage" be locked?

RF Lighting · 10 Aug 2011

Here's one for you then cocky.

Here's a 240V 42W light bulb I've just taken out of the flex drop on my landing.

As you can see it has a resistance of 113.1Ω

Please use ohms law (V = I x R) to tell me what current this 42W bulb will draw at 240V.

ban-all-sheds · 10 Aug 2011

sparkticus · 11 Aug 2011

ban-all-sheds said:

So that's where the PIR acronym SADCOWES comes from

sparkticus · 11 Aug 2011

bernardgreen said:
matt1e said:

Conclusion:

Is there any point to any of this, at least answer that

Click to expand...

I believe there is a point to this conversation.

Mr Cockburn is obviously dedicated to promoting safety in electrical installations. He appears to be promoting the need for care and attention to detail when designing and installing and using electrical equipment.

But his understanding of how safety circuits and equipment function is not yet complete or accurate.

This conversation could be a means to fill the gaps and correct the errors in Mr Cockburn's knowledge. Then his campaign using re-written literature will be more effective as the content will be respected by learned bodies.

It just requires an open mind and some polite but firm implanting of the correct information.

If Mr Cockburn provided a reasonably coherent dialog (whether technically incorrect or not) instead of "injecting" message fragments then I am quite sure that he would have been responded to in a very different way. The subject he raises is interesting, the ridiculous, idiotic way in which he presents himself and his ideas is uninteresting and quite frankly irritating.

david911cockburn · 12 Aug 2011

Mattie,

The IET forum has claimed that the earthing arrangements of the 17th Edition agree with the 16th Edition:
413-02-04 & Table 41C
This claim is rubbish, 413-02-04 just gives two alternative solutions to a high loop impedance value (expected to be found in a TT system), when two earthed conductors are simultaneously accessible; and Table 41C gives us a scientific method of choosing a larger size of fuse wire/cartridge for overload current protection whilst maintaining our speed of automatic disconnection during an earth fault.
Whilst explaining the problems with their definition of Table 41C, I have found that given a choice between questioning 'ohms law' and using ohms law to question 'wilkipedia', you have all chosen to question ohms law!

Paul_C · 12 Aug 2011

david911cockburn said:
I have found that given a choice between questioning 'ohms law' and using ohms law to question 'wilkipedia', you have all chosen to question ohms law!

Not at all, as the problem I set above was designed to illustrate.

If you would care to perform the calculations requested for that first part of the problem, I'll post the second part, which will demonstrate that Ohm's Law applies in both cases.

Spark123 · 12 Aug 2011

41C was to allow an increase in disconnection time where touch voltage was limited. If you read the reg beforehand which referred to the table it said something along the lines of circuits supplying portable and hand held appliances which have a 0.4s disconnection may be increased to 5s.

I don't know why you keep on going on about it anyway as it is from a set of regulations which are no longer current and this table doesn't exist in the new regs.

Paul_C · 12 Aug 2011

And I'm still waiting for a reference to the applicable table in the 13th or 14th editions to which these values were supposedly added during the 1960's (which was long before the 0.4 and 5-sec. disconnection times were added to the regs.).

SgtTrojan · 15 Aug 2011

RF Lighting said:
Here's one for you then cocky.

Here's a 240V 42W light bulb I've just taken out of the flex drop on my landing.

As you can see it has a resistance of 113.1Ω

OOH OOH I know, I know. The resistance of the filament changes when it is heated.. I remember this one from electronics

I haven't been part of this thread (or the others) but as an observer and having read most of the posts made by cockburn he seems very arrogant and the type of person who doesn't know when to stand down. I imagine he has a proper bap nose due to his arrogance and not knowing when he should just be quiet and move on. And if he manages to upset two major figures from two major electrical forums that says it all.

Mental image

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Why would "a bit of bondage" be locked?

Paul_C

Paul_C

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