Today's 2395

[Amp David]

I can't remember whether the qu mentioned if 0.23 was the measured live conductors resistance (ie R1+RN). I myself, didn't use any correction factors, but can see why people have. I thought the that 1.2 correction factor was for correcting the R1+R2 part of the Zs=Ze+(R1+R2) equation, as its carried out as a dead test, and therefore the conductors aren't at operating temperature? But thinking about it... The same logic could be applied to an R1+RN test?

It mentioned that it was the total measured resistance of R1 and Rn and that the testing was done at an ambient temp of 20 deg C.

 

[Spark_shark]

Looks like the correction factor is needed! This was from the previous chief examiners report on c and g website...

"When asked to calculate the voltage drop for a given scenario most candidates failed to include a temperature compensation factor in their calculation. As testing was carried out at 20 oC and voltage drop is calculated with the conductors at operating temperature this compensation needs to be included in the calculation."

damn it! I didn't use any correction factor, so don't know if I'll have picked up any points for that, or the question that followed on from it asking if it complied or not? I but it complied, which it would've with or without the correction factor, as both were <11.5 volts

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I put*

 

[long512]

well, spark_shark you had me thinking i had done the right thing there. Until i remember'd that for reasons unknown to me my correction factor was something like:-

40x0.23=9.2v correction factor of 1.2 required, but i thimk i have done 1 / 1.2, wich then lowers the bloody voltage to 7.6v!!!!!!!!!!!!!!!!
when it should have gone up to 11.04v!!!!!!!!!!
were i got 1 divided by 1.2 from?????????????? put it down to resit nerves!

 

[Amp David]

Done the online tonight and managed a 98%:wink_smile: