New install but low IR

[TPES]

Newly installed lighting circuit.

Feed to corridor switch, then a 2G switch, eme test key switch and 2W switch. Corridor no more that 30 meters in length. Around 10 x 28w 2D light fittings and 8 eme lights.

I/R test shows 52.5 on N-E & 502 on L-E.

could this just be trapped or slightly damaged cables by plasterers and other trades or am I missing something else?

It just really pee's me off when I have to put low IR results on a new EIC's.

 

[telectrix]

are those readings in Mohms?

 

[Martin Bradley]

what is the reading if you connect PN/ E ? dont forget about the electronic components.

 

[telectrix]

and, if it's just been plastered, damp everywhere.

 

[TPES]

Yes all Mohms, Which i know is a pass but im just pee'd off there low values, plastering was done about 2 weeks ago. i know there is sensitive equipment on the circuit so only way is to join L/N - E

 

[IQ Electrical]

Newly installed lighting circuit.

Feed to corridor switch, then a 2G switch, eme test key switch and 2W switch. Corridor no more that 30 meters in length. Around 10 x 28w 2D light fittings and 8 eme lights.

I/R test shows 52.5 on N-E & 502 on L-E.

could this just be trapped or slightly damaged cables by plasterers and other trades or am I missing something else?

It just really pee's me off when I have to put low IR results on a new EIC's.

I know everyone likes to see 'full scale deflection' on a new circuit IR test but to call 52.5 Million Ohms 'low IR' on a job that you've indicated has just been plastered means you maybe don't understand the science behind the test.

 

[Sintra]

Not being funny but your IR tests should be done with all the loads disconnected as it's an EIC and no limitations are permitted.

 

[TPES]

I know 52.5 mohms is not low compared to some I/R results, But as i am used to seeing >1000 on my meter across each conductor on new I/R tests this is why this is frustrating me, the plastering was done a couple of weeks ago and is in no way damp. I know EIC should have no limitations, of course i will get inacurate readings if my lighting is connected this is why i didnt put 500v down L-N, and just testing to the switches is not an option so i guess ill be taking each fitting down and joining out each light, then re-testing.

 

[tony mc]

Before making extra work for yourself I would honestly give it more time to dry out IMO.

 

[IQ Electrical]

Before making extra work for yourself I would honestly give it more time to dry out IMO.

I'll second that, sometimes over a month in an unheated building in damp, cold conditions.

 

[TPES]

ok, fair comment.. cheers chaps! ill leave it abit longer.

Thanks

 

[Farmelectrics]

should do your ir tests before connecting any light fittings ie emergencys etc

 

[TPES]

should do your ir tests before connecting any light fittings ie emergencys etc

I assume you mean temporary connecting out the cables at each fitting so you can do IR tests, then re-connect back up, is this what you would do on a row of say 17 lights?

 

[TPES]

Or just test L/N - E as to not damage the sensitive equipment connected