MI 3155
Eurotest
XD
Test and measurements
177
7.34
AUTO IT – Auto test sequence for IT earthing
system
Tests / measurements implemented in AUTO IT sequence
Voltage
Z line
Voltage Drop
ISFL
IMD
Figure 7.115: AUTO IT menu
Measurement parameters / limits
Fuse type
Selection of fuse type
[Off, gG, NV, B, C, D, K, Custom]
Fuse I
Rated current of selected fuse
Fuse t
Maximum breaking time of selected fuse
I (
U)
1)
Rated current for
U measurement (custom value)
Test
Test mode
[MANUAL R, MANUAL I, AUTO R, AUTO I]
t step
Timer (AUTO R and AUTO I test modes)
[1 s
… 99 s]
Isc factor
Isc factor
[0.20 … 3.00]
Limit(
∆
U)
Maximum voltage drop
[3.0 % ... 9.0 %]
Rmin(R1,R2)
Min. insulation resistance
[Off, 5 k
… 640 k
],
Imax(I1,I2)
Max. fault current
[Off, 0.1 mA ... 19.9 mA]
Imax(Isc1,Isc2) Maximum first fault leakage current
[Off, 3.0 mA ... 19.5 mA]
Ia(Ipsc (LN))
Minimum short circuit current for selected fuse or custom value
1)
Applicable if Fuse type is set to Off or Custom.
Refer to
Fuse tables guide
for detailed information on fuse data.
Connection diagram
Figure 7.116: AUTO IT measurement