high R1+R2 on radial lighting with emergencys

[jackhammer]

hello, just started in this game and am currently dead testing some lighting radials made of gu10 and low voltage emergencys, the R1+R2 readings are a bit high in comparison to table 11 appendix 1 in the osg. Is this the transformer packs causing this? Also am i right in thinking to disconnect the said transformer packs for insulation as pushing 500v through them could damage them? If any experianced sparks could give me some valuable imformation it would be much appreciated before i start pulliong every lamp down and making a mess of the ceiling to check connections etc.

 

[Guitarist]

How are you doing your R1+R2? Are you not shorting your supply cable line and cpc then removing lamps anyway to test?

 

[ipf]

What do you mean by 'a bit high'. What do you think it should be?
And what is the actual ? Shouldn't affect R1+R2, if doing correctly. Link L and N and IR test to earth.

 

[jackhammer]

yes shorting line and cpc at db and testing switch line and cpc on last lamp in radial, there is one or two emergencys in place of gu10s throughout the circuit and the conductors are hard to access now as job is near completion (no pressure lol) hence i dont want to start pulling the ceiling down.

 

[jackhammer]

My reading is 2.25ohms and i calculate 50m run 1.5mm line 1mm cpc it should be 1.51 ohms so im a ohm out.

 

[Guitarist]

If it is not practicable to remove loads for IR testing, then as ipf says, link L-N and test to earth with switch on, and L-N with switch off to test as much wiring as you can. Yes, you would have to remove transformers and lamps if you are doing L-N IR test.

 

[sedgy34]

surely the circuit has been designed to meet the requirements so cant be high if new installation

 

[Guitarist]

My reading is 2.25ohms and i calculate 50m run 1.5mm line 1mm cpc it should be 1.51 ohms so im a ohm out.

Have you nulled your leads?

 

[ipf]

As above re leads and crocs. 0.74 ohms out.

 

[jackhammer]

yes leads nulled could the transformers be making the reading high?

 

[jackhammer]

not my design but yes i believe everything is good and meets the requirements from the visual point of view, its not my install so just trouble shooting as to why the continuity reading is a bit high? just asking for some experienced help as obviously i want the circuit to be safe.

 

[ipf]

yes leads nulled could the transformers be making the reading high?

No, as long as they're not wired in series.lol.

 

[tony mc]

Is there 2 way switching connected ?

As the resistance of the strappers could up your reading!

 

[sedgy34]

how many points are on this circuit??

 

[jackhammer]

no just a single switch for each circuit i will need to get the installer to re trace his circuit and see how accurate his pacing is i think lol!