Be careful, yes it can be pme, why not? The point of an additional electrode is to limit touch voltage on a broken pen, if you not prepared to attain a value which safely limits the voltage, then why bother, just TT it.
Swimming Pool Installation
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How can a single cable from a Tx to a single consumer be "conventional" "PME"?
Please explain, in detail.
The Tx electrode is that at the Tx, thus the Star point earth for the Tx.
Even IF the DNO drop rods along the SINGLE supply cable from the Tx, this would not make it a PME supply requiring all of the safeguards of "normal" PME as there would be NO possibility of diverted N currents.
1 Tx, 1 Consumer, where can the diverted N currents come from?
Why TT something when you have a perfectly good very low impedance DNO earth?
What are the chances of a broken PEN, risk assessment?
Also, you need to be careful to understand the subtleties of PME & PME & TN-C-S.
Finally for now, got to dash of for a few minutes, it is not definite that the supply is actually TN-C-S, I recently worked on an install "out in the sticks" and I don't do much domestic, that was a pole mount Tx 11kv/400V, which appeared to be TN-C-S, but upon careful checking was actually TN-S, not immediately easy to spot due to the install methods used by the DNO.
Please explain, in detail.
The Tx electrode is that at the Tx, thus the Star point earth for the Tx.
Even IF the DNO drop rods along the SINGLE supply cable from the Tx, this would not make it a PME supply requiring all of the safeguards of "normal" PME as there would be NO possibility of diverted N currents.
1 Tx, 1 Consumer, where can the diverted N currents come from?
Why TT something when you have a perfectly good very low impedance DNO earth?
What are the chances of a broken PEN, risk assessment?
Also, you need to be careful to understand the subtleties of PME & PME & TN-C-S.
Finally for now, got to dash of for a few minutes, it is not definite that the supply is actually TN-C-S, I recently worked on an install "out in the sticks" and I don't do much domestic, that was a pole mount Tx 11kv/400V, which appeared to be TN-C-S, but upon careful checking was actually TN-S, not immediately easy to spot due to the install methods used by the DNO.
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If the tx is earthed at the origin and then at any other point then it's tncs pme. The diverted neutral currents will come from the installation connected to the tx. Why TT? I m not saying TT it, just don't see the point of ridding a pme unless you are prepared to acquire the correct Ra. On the note of pnb, balanced three phase, where's the star point, at the origin or at the electrode at the consumer end.
The star point will be at the TX, it has to be to comply with ESQCR.
Until the contractor drops rods at the consumers install it will NOT be PME, I've been through this with people more qualified and competent than you trust me, unless you are the pseudonym of one of those who I have been through this with elsewhere.
Most of those people are VERY closely linked with JPEL/64.
Now even IF the install has rods dropped at the origin & sub DB's you cannot get imported circulating N currents as there can never be any as there are no other installations from which to import N currents.
The origin is supplied from a dedicated Tx.
Your explanation is not sufficiently detailed.
Until the contractor drops rods at the consumers install it will NOT be PME, I've been through this with people more qualified and competent than you trust me, unless you are the pseudonym of one of those who I have been through this with elsewhere.
Most of those people are VERY closely linked with JPEL/64.
Now even IF the install has rods dropped at the origin & sub DB's you cannot get imported circulating N currents as there can never be any as there are no other installations from which to import N currents.
The origin is supplied from a dedicated Tx.
Your explanation is not sufficiently detailed.
Where does it state that external diverted neutral currents are a prerequisite of pme?
Chr!s , Im afraid that in this instance mr sidewinder is more correct than incorrect,
my first foray into this thread and my opinion would be 'proper localised PME' is the way to go,
not having seen the actual site or install I would be more than 99.99% certain it is not at present a proper PME system,
rod the submain at the pool end, and at source, and perhaps anywhere else the OP feels may be required,
but I wouldnt be TT'ing in these circumstances, and believe me, that is something you will seldom hear me say.
my first foray into this thread and my opinion would be 'proper localised PME' is the way to go,
not having seen the actual site or install I would be more than 99.99% certain it is not at present a proper PME system,
rod the submain at the pool end, and at source, and perhaps anywhere else the OP feels may be required,
but I wouldnt be TT'ing in these circumstances, and believe me, that is something you will seldom hear me say.
no,
but I have always said that PME, if done properly, is good,
it is when TNCS is masquerading as PME that we have major problems.
Only pulling your leg mate.....
It's nice to have this type of thread back on the forum that makes you think & go away to have a read up, rather than the run of the mill stuff (not that I have a problem with run of the mill)
It's nice to have this type of thread back on the forum that makes you think & go away to have a read up, rather than the run of the mill stuff (not that I have a problem with run of the mill)
It does NOT, however, why are the requirements of PME bonding so rigorous?
You obviously are out of your depth with no clue so please leave it to those who know.
I know,
TBH I saw the title and thought pumps, underwater lights etc, loads of stuff I know little about, so only now have I decided to have a look in,
yep, good to have threads like this to promote reasons why/why not something should be done in any particular manner
Errrm clearly you are out of your depth, if the pen opens, then that one installation will have diverted currents within the installations bonding, the bonding may carry most of the diverted neutral current, so please explain your remarks.
'proper' PME does not have this problem.
not wanting to have a go Chr!s , but do you understand the differences between PME & TNCS ? and to add to that, TT even?
and their inherent advantages and flaws?
Chris,
I am far from out of my depth, and once again I find that a poster on the forum ignores my questions and will not answer them, but merely fires questions back at me.
If you took the courtesy to answer the points from previous posts in full then you would get a much kinder response.
In a SINGLE consumer install there can be no EXTERNAL diverted N currents, you have failed to explain how there can be in response to my previous post.
Once you explain in full how there can be no external diverted N currents in an install supplied be a dedicated HV Tx then we can go on.
Why is it so many posters on forums will not answer questions that are posed to them in responses before they ask other questions?
I may well have to leave this thread before I have to ban myself because I have to respond to, well I can't say else again I'll have to get banned.
I am far from out of my depth, and once again I find that a poster on the forum ignores my questions and will not answer them, but merely fires questions back at me.
If you took the courtesy to answer the points from previous posts in full then you would get a much kinder response.
In a SINGLE consumer install there can be no EXTERNAL diverted N currents, you have failed to explain how there can be in response to my previous post.
Once you explain in full how there can be no external diverted N currents in an install supplied be a dedicated HV Tx then we can go on.
Why is it so many posters on forums will not answer questions that are posed to them in responses before they ask other questions?
I may well have to leave this thread before I have to ban myself because I have to respond to, well I can't say else again I'll have to get banned.
Errrm clearly you are out of your depth, if the pen opens, then that one installation will have diverted currents within the installations bonding, the bonding may carry most of the diverted neutral current, so please explain your remarks.
I've answered, what's the relevance of external diverted neutral currents, I've explained to you how that one installation may have its own diverted currents within its bonding, you need to clearly explain the issue with the lack of further external diverted current.
Neutral currents within the install are not diverted into the install from outside.
You obviously do not understand the terminology I was using, hence my previous posts.
You obviously do not understand the terminology I was using, hence my previous posts.
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