Neutral in zs tests ? If zs is

[Wilson12]

Hello if zs is ze+ r1 + r2
Why when we test do we need the neutral whilst doing zs tests ?

 

[telectrix]

Ze + (R1 +R2). note the use of caps. r1 and r2 are totally different , denoting end - end for a ring circuit. youneed the 3 lead test for lo-current no trip testing, unless you have one of the later mft's that can do 2 lead no trip tests.

 

[Richard Burns]

The neutral can supply power to the meter's internal test circuit without drawing a current through the earth that may distort the test result.