My point is that he has very limited practical experience.
Re What is a "Live conductor"?
- Thread starter ban-all-sheds
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We all have our problems with BAS, and quite often wish that he could change his style/tone (and do a little less 'policing') but I don't think it's fair to suggest that he 'pretends' to be an electrician just because his knowledge is such that, to many people, he probably appears to be an electrician.
I imagine that some people think/believe much the same about me, but at least they don't accuse me of pretending to be an electrician.
Kind Regards, John
To be fair John you really don't carry on the way that ban-all-sheds does. You are not abrasive like he is, though you are not afraid to offer your opinion which is fair enough. I really don't think there is any parallel between yourself and the aforementioned user.
No, it's not in my nature to behave as he does, nor to do so much hunting for little things to criticise/'correct' (or 'rant about'!!). However, I am probably somewhat at risk of 'being mistaken for an electrician' in a similar way to what undoubtedly sometimes happens with him.
Kind Regards, John
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Very early in my electrical career I was repairing portable traffic lights, they were the first breed of traffic sensing 1970's and were supplied with Peak radar heads, these heads were not very sensitive and would not change all the time, so were replaced with Mullard heads, in the depot they worked A1 but as soon as I took them out they failed, it seemed they needed a 55 - 0 - 55 volt supply and our generator was giving out 110 volt line - line with no centre tap which is why they failed, so we were supplied with an inductance centre tapped to change the generator output to being centre tapped.
However traffic light 7 core cable was often damaged and with one cable damage was causing the traffic light heads to give people a shock, however there was no cross connection with the cable, it had simply lost it's earth connection, it then transpired that this was due to these Mullard radar heads which actually used the centre tap and did not simply have it as a return in case of fault. At this point the councils legal department got involved, and it seems 25 volt is enough to kill a cow, so the heads were all withdrawn and it seems the inductance was then fitted inside the head so they worked on 110 volt and did not use the centre tap.
I was only a young lad at the time, but it would seem even the the 1970's using an earth wire to send current down is not permitted, even if a very small current, don't know what was inside the head, but head not plugged in voltage was x - 0 - y where x - 0 + y - 0 = 110 but with head plugged in I got 70 - 0 - 70 but still a 110 volt phase to phase.
Since then I have come across some interference suppression systems which also have produced current on the earth cable, these have also been removed from service as faulty, I know there are systems where we do have high earth currents and with those systems the earth cables are doubled up, however no system should be designed so that the earth actually is expected to carry non fault current. Other than to sacrificial anodes.
I don't think I have ever been able to fully work out the earth system, I have seen some odd things in my time, like huge resistors between the DNO earth and site earth, and diodes in the earth supply. I know why they were there, without the resistor the earth current could under fault conditions exceed the capacity of the cable, and without the diodes the earth could erode the hull of the boat away and very quickly cause the zinc sacrificial anodes to need replacing.
However with no current limiting device in the earth I question how diodes in the earth are protected? I know the hull is painted so there should not be that much area in contact with the water, however still think a 63 foot narrow boat in the cut made of steel must be quite a good earth never actually tried to measure it but suspect a lot of current could flow?
OK with a narrow boat TN-C-S is not permitted. But just seems wrong to expect any current to flow down an earth wire other than fault current?
However traffic light 7 core cable was often damaged and with one cable damage was causing the traffic light heads to give people a shock, however there was no cross connection with the cable, it had simply lost it's earth connection, it then transpired that this was due to these Mullard radar heads which actually used the centre tap and did not simply have it as a return in case of fault. At this point the councils legal department got involved, and it seems 25 volt is enough to kill a cow, so the heads were all withdrawn and it seems the inductance was then fitted inside the head so they worked on 110 volt and did not use the centre tap.
I was only a young lad at the time, but it would seem even the the 1970's using an earth wire to send current down is not permitted, even if a very small current, don't know what was inside the head, but head not plugged in voltage was x - 0 - y where x - 0 + y - 0 = 110 but with head plugged in I got 70 - 0 - 70 but still a 110 volt phase to phase.
Since then I have come across some interference suppression systems which also have produced current on the earth cable, these have also been removed from service as faulty, I know there are systems where we do have high earth currents and with those systems the earth cables are doubled up, however no system should be designed so that the earth actually is expected to carry non fault current. Other than to sacrificial anodes.
I don't think I have ever been able to fully work out the earth system, I have seen some odd things in my time, like huge resistors between the DNO earth and site earth, and diodes in the earth supply. I know why they were there, without the resistor the earth current could under fault conditions exceed the capacity of the cable, and without the diodes the earth could erode the hull of the boat away and very quickly cause the zinc sacrificial anodes to need replacing.
However with no current limiting device in the earth I question how diodes in the earth are protected? I know the hull is painted so there should not be that much area in contact with the water, however still think a 63 foot narrow boat in the cut made of steel must be quite a good earth never actually tried to measure it but suspect a lot of current could flow?
OK with a narrow boat TN-C-S is not permitted. But just seems wrong to expect any current to flow down an earth wire other than fault current?
But unlike you I can read properly.
Define " electrician " Is it (a) One who follows a set of rules about how to install cables and fittings or (b) One who can construct those rules based on a comprehensive understanding of electrical circuits and electrical safety
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So far, in the discussion of this issue, in two threads, you have called me a moron, a buffoon, and a liar, and all because when you said that a cpc cannot be considered a live conductor because it does not carry any current in normal use I pointed out that sometimes it does.
And now you are trying the diversionary tactic of an ad hominem attack instead of focusing on the issue.
You aren't very good at this, are you....
As you presumably realise, I was using the word in it's conventional sense, to refer to someone whose 'occupation' was that of an electrician - regardless of considerations of training, knowledge, qualifications, experience, skill or competence.
There is nothing stopping me offering 'electrical services', for payment, to the general public, and if I proved to be competent (i.e. satisfying Part P) and obeyed rules regarding notification etc., no-one could 'find fault' with me - despite the absence of formal training/qualifications etc. If I did that, I would call myself an electrician.
Kind Regards, John
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FWIW as a DIYr visiting the site I do not see BAS as an "electrician", I see him as a DIYr that has read and understands the regs.
You do not need to e an "electrician" to be able to read and understand BS7671, I'm not and I have read it and understand what I have read (well most of, some does not apply to me so never bothered with those bits).
However if I have any reg questions I'm more than happy for BAS to answer them as I see his knowledge of the regs as being greater than mine and several so called electricians on here
You do not need to e an "electrician" to be able to read and understand BS7671, I'm not and I have read it and understand what I have read (well most of, some does not apply to me so never bothered with those bits).
However if I have any reg questions I'm more than happy for BAS to answer them as I see his knowledge of the regs as being greater than mine and several so called electricians on here
A good electrician will ( or should ) be able to identify those situations where the regulations cannot be applied as written and then devise and design a solution that is satisfactory and safe .
A poor "electrician" ( a house bashing cable and fittings installer ) may in similar situations comply with the letter of the regulations with the result that a hazardous installation is passed as being compliant with BS7671. ( it is compliant but still hazardous due to circumstances not covered in the regulations )
A poor "electrician" ( a house bashing cable and fittings installer ) may in similar situations comply with the letter of the regulations with the result that a hazardous installation is passed as being compliant with BS7671. ( it is compliant but still hazardous due to circumstances not covered in the regulations )
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