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If i were doing an EICR [which i do not] and i came across a TT installation with an isolator marked up as being a single pole one, it would be getting a C2 for a certainty..

It is not for me to be guessing or testing the switch function....
Surely "testing the switch function", ie that it's functioning correctly, is exactly what you should be doing on an EICR?

 
Er no..... Would you try to test, say a 32A mcb to make sure that it really was one?? or that it tripped at the right current, Er... no. You would just make sure that a 32A mcb seemed to be appropriate for the circuit it was protecting and that Zs was low enough for it to operate as intended..

If an application calls for double pole isolation, and then you come across an item clearly marked up as a single pole one, what would you want to test it for?? It would be coded and that would be that..

Say you came across one of the "fire proof" CU's, would you try to set fire to it to see if the thing really was fire proof?? er, no... You would just be guided by the applicable markings on it. this is all i am saying

Hi Lurch, I will answer your points later!! In a big rush right now, got to shoot off!!!

john..

 
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Marking requirements are specified in EN 60947-1 & -3
Any chance we could be told what these requirements are in the current context of the SP/DP symbol?

If an application calls for double pole isolation, and then you come across an item clearly marked up as a single pole one, what would you want to test it for?? It would be coded and that would be that..
But it isn't clearly marked up as such, it has a marking on it which could in some situations be interpreted as marking the device as SP switching, but then the part number is a DP isolator so you would have to take that into consideration as well. The markings are ambiguous at best.

Hi Lurch, I will answer your points later!! In a big rush right now, got to shoot off!!!
Looking forward to it! :)

 
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Er no..... Would you try to test, say a 32A mcb to make sure that it really was one?? or that it tripped at the right current, Er... no. You would just make sure that a 32A mcb seemed to be appropriate for the circuit it was protecting and that Zs was low enough for it to operate as intended..

If an application calls for double pole isolation, and then you come across an item clearly marked up as a single pole one, what would you want to test it for??...
Would I test an MCB for tripping current? No, I don't possess the appropriate test equipment and the regs don't require it.

However, I do check circuit breakers and isolators for correct isolation as outlined in Appendix 6 of the current regs. See page 431, Examples of items requiring inspection for an EICR, Isolation and Switching, Isolators (537.2), 4) Correct operation verified (612.13.2).

 
Hi Steps,

Yes i would shut an isolator off and make sure it did go off and seemed undamaged, not sure that i would be getting out a meter to make sure it was shutting off the neutral too [if that was required/intended] especially where the makers marking indicated that the thing was an SP device with a solid neutral just incase the makers had got it wrong.. So what i am saying is, that if i found a switch clearly marked as SP when a DP one was required it would get a code. One should not have to guess at the function of devices, if the makers mark it as SP then so far as i am concerned it is. You would not expect to have an MCB with the wrong rating marked on it, or the same with an RCD or a fuse with the wrong rating on it.

john...

 
Hi Lurch,

You say that "But it isn't clearly marked up as such, it has a marking on it which could in some situations be interpreted as marking the device as SP switching, but then the part number is a DP isolator so you would have to take that into consideration as well. The markings are ambiguous at best"

How are the marking of this switch ambiguous? They clearly show it is a single pole device. Never mind it look, like a DP one, one has to assume that the makers symbols are correct. When you connect something up, do you just stick the wires where you think, or do you look to see which terminal does what according to the numbers on them and the symbols on the device?? Unless you look at the numbers and symbols you would not have much of an idea which connection does what, this is why the things have numbered terminals and symbols in the first place..

john..

 
They clearly show it is a single pole device.
No.

I appreciate you are a keen DIYer and have pretty good electrical knowledge but you cannot keep stating things as fact which clearly aren't fact and are opinions made by yourself.

 
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Ok, tell me why these switches have the same part number but different symbols. The sybol itself mean an "on load" isolator. There are different symbols for SP and DP, so why the difference on the switches???

http://i.ebayimg.com/images/i/291506625407-0-1/s-l1000.jpg

I did not invent the IEC symbols, nor the rules that require there use, they are there for a reason. Do you think car tyre makers could manufacture tyres and just print any old symbol on them.. Why did the switch makers change the symbol?? Someone, must have had a little word with them.

As you say, I am only a DIY type and you will have forgotten more than i will ever know, but the makers are REQUIRED to use these symbols and use them correctly for a reason..

It is not just my opinion that the makers use these symbols, if they want to sell the stuff in the EU they have no choice..

john..

 
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So what are these requirements exactly then? Which exact part says that the diagrammatically correct schematic of the device should be stamped upon it?

I at no point have said anything should be ignored or done incorrectly, I have not said whether anything should be stamped on these devices as I do not know the relevant standards and do not have access to the documents in question, you keep insisting that there is some standard that these devices are contravening but have not stated which standard they are contravening and have failed to quote the relevant part of the standard applicable.
 

All I have said is that you cannot keep insisting these devices are all incorrectly labelled when you do not know what the labelling on them should be.

 
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How is normal safe isolation goin to tell you that??

Me myself, for a single phase isolator say, i test between phase and neutral on the load side, yep definitely is on,,[important that] now turn it off.

Test between phase and neutral - dead

Test between phase and earth - dead

Test between neutral and earth - dead

If you REALLY wanted to test if the switch "switched neutral" you would have to test [with the switch off] between line side phase and load side neutral. Not really part of standard safe isolation though..

Obviously different with three phase, [check phase to phase and individual phases]

I do not do any of this isolate by means of an MCB and work on a single circuit. The LOT goes off or they can go and get someone else. [Having once worked on a circuit where all was dead, then someone switched on a load on another circuit that some prat had connected to the neutral of "my" circuit...!!]

Funnily enough though, anywhere you have a TNS or TNCS supply there is no requirement to be able to isolate the neutral anyway, EXCEPT in domestic installations or with ANY situation where you have a TT installation..

[You DO have to have provision to disconnect the neutral though for the purposes of testing] Soooooo, DP isolator on single phase and either a 4 pole one or a 3 pole AND a neutral link on three phase.

john...

 
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