HT instruments EQUITEST5071 - Manual (Page 30)

EQUITEST 5071
EN - 28
At the end of the test,
the instrument gives out
a double sound to
indicate that test has
been correctly
performed and the
following screen
appears on the display. LOOP 30.11.12
Value of Phase-Earth
resistance expressed in

1.07

215A
Freq=50.0HZ
VP-N=231V Vp-PE=231V
R
A

Value of the assumed Phase-
Earth short-circuit current
calculated using the formula
reported below
Operating mode FUNC
N.B. In TT systems, the value of overall earth resistance may be considered similar to
the value of Phase-Earth fault loop impedance, measured by the instrument.
Therefore, in compliance with standards, the measured value may be taken as the
value of the system’s earth resistance.
Formula used for calculating the assumed short-circuit current:
PE
N
CC
Z
U
I

where: U
N
= Phase-Earth voltage 127 if
100< V
mis
 150
230 if 150V< V
mis
260
Z
PE
= measured Phase-Earth impedance
6. The results can be saved by pressing the SAVE key twice (see § 7.1).