special locations

[steptoe]

It's funny all this bonding and sup bonding. I always cross connect boilers but my assessor seems to think that it's to much... If it on a rcd it's ok just to bond the incoming gas and water supply. If I was the op I would cont test and see if it needs bonding.

Most sparks now a days only bond water and gas at incoming

Boilers havent needed cross bonded for a long time now,

pre 16th,

for a boiler to meet the relevant BS it requires the manifold to be internally 'crossbonded' anyway, so you are just putting a fancy decoration on it.

 

[NozSpark]

I saw some cross bonding the other day where they didn't even scrape the 5 layers of paint off the pipes first:O

 

[green-hornet]

I have some advise for you, which will stand you in good stead for the future, cancel your assesment until you are conversant with the regulations.Then come back and ask something which is chalanging.

 

[chrisg1979]

It's no wonder some members of this forum don't feel comfortable asking questions.

 

[Theorysparky]

Boilers havent needed cross bonded for a long time now,pre 16th,

for a boiler to meet the relevant BS it requires the manifold to be internally 'crossbonded' anyway, so you are just putting a fancy decoration on it.

But if the boiler was in a room containing a shower or bath you can cross bond all the pipes,the lights and shower from there

then go to your rad,hot+cold etc and test

sometimes its easier to do it that way

note on the cert,,,,,,,thankyou very much

 

[SPECIAL LOCATION]

It's no wonder some members of this forum don't feel comfortable asking questions.

And it

 

[ccfc]

Butler

To find if a piece of metal work is a extranous part IR test at 500v between part and known earth if equal to or greater than 22000 ohms it doesnt require bonding as 500/22000 = approx 22mA so 230/22000 = 10mA which is the let go threshold.

 

[Doc Hudson]

ButlerTo find if a piece of metal work is a extraneous part IR test at 500v between part and known earth if equal to or greater than 22000 ohms it doesnt require bonding as 500/22000 = approx 22mA so 230/22000 = 10mA which is the let go threshold.

May I just add some extra detail to your post ccfc. An insulation resistance test would not be able to show 22,000ohms. Just show the multiples of 0.01Mohms, 0.02Mohms, 0.03Mohms etc. So 0.01Mohms would be considered extraneous as 0.01Mohms = 10,000ohms. and 0.03Mohms is clearly above 22,000ohms as 0.03Mohms = 30,000ohms. But 0.02Mohms could be anything in the range 20,000ohms to 29,999ohms as 0.02Mohms = 2x,xxxohms and would need a bit more investigation. I would consider using the 250v test range is adequate to get this continuity reading rather than the 500v range.

Doc H..

 

[ccfc]

Doc

Much more eloquent than i can explain. I realise that the value i said would not be shown on a IR test, i was just trying , badly, to show what the values mean to give the guy a bit of help.

Cheers

Neil

 

[green-hornet]

It's no wonder some members of this forum don't feel comfortable asking questions.

I could defend myself in this instance by saying that, as an assessor I would expect fundemental questions be answered without hesitation, if an answer required a particular figure, which I would never presume anyone of being able to recall, then as ;long as you can find the relevent section, and answer in the book, then I would be happy to assess you as competant. Ask me a question as basic as this on assessment, and I would instantly fill a load of crosses in a form, but would have little impact in keeping you from what your obviously not cut out to do.