Line Impedance And Prospective Short-Circuit Current - METREL MI 3122 Instruction Manual

MI 3122 Smartec Z Line-Loop / RCD

5.3 Line impedance and prospective short-circuit current

Line impedance is measured in loop comprising of mains voltage source and line wiring. It
is covered by requirements of the EN 61557-3 standard.
See chapter 4.1 Function selection for instructions on
key functionality.
Test parameters for line impedance measurement
FUSE type Selection of fuse type [---, NV, gG, B, C, K, D]
FUSE I Rated current of selected fuse
FUSE T Maximum breaking time of selected fuse
Lim Minimum short circuit current for selected fuse.
See Appendix A for reference fuse data.
Connections for measurement of line impedance
Ro R
E
Figure 5.12: Phase-neutral or phase-phase line impedance measurement – connection of
Line impedance measurement procedure
Select the
Z-LINE

Select test parameters (optional).

Connect test cable to the top of the instrument.

Connect test leads to the item to be tested (see figure 5.12 ).

Press the TEST key to perform the measurement.

Store the result by pressing the MEM key (optional).

plug commander and universal test cable
function using the function selector switch.
Figure 5.11: Line impedance
N
32
Line impedance
PE L
L1
L2
L3
N
PE