calculating Zs with only R2 reading

[egginyourface]

is it possible to calculate zs by only using r2 + ze reading??

 

[egginyourface]

i could have done r1 + r2 but for some reason i decided not to o it...its the 1st and last and wont ever be doing this again. will be doing the r1+r2 method next time.

still feel that theres nothing wrong with it

 

[malcolmsanford]

For a PIR I have to say that in a commercial situation there are many times you can't do the R1+R2 test, that is why your schedule of results allows you to use a R2 only reading, in fact if you wished you can even do R2 for an EIC, but to be honest I don't think I would want to do just that.

R2 is your continuity of the protective conductor and if you can prove that throughout the circuit and do your Zs test then R1 + R2 for a PIR is perhaps not so critical.

It is to be remembered that the tester on a PIR decides with his experience and competency which tests are required, even the GN 3 in the PIR section only advises a Zs test at the origin of the installtion, at a DB, a socket outlet or the end of a radial circuit, so lighting circuits are pretty much not needed.

So if you know your R2 then yes in theory you could calculate your R1, but as in the age old question why would you want to

 

[Farmelectrics]

yes you can its not the prefered way but mathematicaly you can better to live test gives you a truer reading

 

[morph]

ok so what is the lenght? a line conductor in a light circuit may well be longer than the cpc , so you cant just say its 1.5 mm/1.0mm etc
and what resistances do all the switches have??

 

[Sparky Ninja]

ok so what is the lenght? a line conductor in a light circuit may well be longer than the cpc , so you cant just say its 1.5 mm/1.0mm etc
and what resistances do all the switches have??

once again, these opinions of yours are warranted and any experienced competent person will take these into consideration. However they cannot be used to oppose the fact that by design or calculation, these methods are accepted.

This is going round and round in circles.

 

[morph]

how can it be done though if you dont know the lenght?
the line conductor is not the same lenght as the cpc , this is why i say it is not possible
the op said he did an R2 reading and asked if could then work out the ZS, he cant is the only answer because he does not know the resistance of R1 and it cant simply be guessed.
design calcs dont come in to it , this was a live situation where all the values and figures are not available to calculate ZS.

 

[Sparky Ninja]

how can it be done though if you dont know the lenght?
the line conductor is not the same lenght as the cpc , this is why i say it is not possible
the op said he did an R2 reading and asked if could then work out the ZS, he cant is the only answer because he does not know the resistance of R1 and it cant simply be guessed.
design calcs dont come in to it , this was a live situation where all the values and figures are not available to calculate ZS.

Yes you can, you will need to know the circuit length and the size of the conductors.

Read the whole thread, it helps..

 

[morph]

i dont need to , i am answering the op, besides i have read it and the fact does not alter, zs can not be calcullated with ZE and R2 as originaly asked

 

[morph]

is it possible to calculate zs by only using r2 + ze reading??

NO
end of

 

[morph]

Yes you can, you will need to know the circuit length and the size of the conductors.

we dont know the circuit lenght though

 

[Des 56]

NO
end of

Damn,was just getting geared up to post my opinion
I might have agreed
I might have said what a load of Bo--cobblers

The thread ended abruptly. so it will forever remain the opinion that never was

 

[pushrod]

Damn,was just getting geared up to post my opinion
I might have agreed
I might have said what a load of Bo--cobblers

The thread ended abruptly. so it will forever remain the opinion that never was

you might have just sat on the fence - and got splinters up your bum

 

[Sparky Ninja]

Yes you can, you will need to know the circuit length and the size of the conductors.

we dont know the circuit lenght though

but it can still be done...

 

[Sparky Ninja]

NO
end of

oh,

now I'm convinced.

 

[morph]

Damn,was just getting geared up to post my opinion
I might have agreed
I might have said what a load of Bo--cobblers

The thread ended abruptly. so it will forever remain the opinion that never was

LOL i apolise never meant to sound rude