METREL MI 3125 User Manual

MI 3125 EurotestCOMBO Line impedance
41
5.7 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.
Figure 5.27: Line impedance
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
L1
L2
L3
N
PE
R E
Ro
LPEN
L
/
L
1
N
/
L
2
P
E
/
L
3
N/L2
L
/
L
1
PE/L3
Figure 5.28: Phase-neutral or phase-phase line impedance measurement – connection
of plug commander and universal test cable
Line impedance measurement procedure
 Select the Z-LINE function using the function selector switch.
 Select test parameters (optional).
 Connect test cable to the instrument.
 Connect test leads to the item to be tested (see figure 5.29).
 Press the TEST key to perform the measurement.

METREL MI 3125 Specifications

General

Type	Multifunction Installation Tester
Insulation Resistance	Yes
Continuity Test	Yes
Loop Impedance	Yes
RCD Testing	Yes
Voltage Measurement	Yes
Frequency Measurement	Yes
Display	LCD
Power Supply	6 x 1.5 V AA batteries
Loop Resistance Resolution	0.01 Ω
Frequency	45 - 65 Hz
Line Voltage Resolution	1 V
Insulation Resistance Test Voltage	50 V, 100 V, 250 V, 500 V, 1000 V
Insulation Resistance Resolution	0.01 MΩ
Continuity Resistance Resolution	0.01 Ω
Test Current	200 mA
DC Voltage	Up to 600 V
Loop Resistance	0.0 Ω - 1999 Ω
Line Voltage	Up to 550 V
Line Voltage Accuracy	±2% ±2 digits
Rated Residual Current	10 mA, 30 mA, 100 mA, 300 mA, 500 mA
Insulation Resistance Range	0.01 MΩ to 1 TΩ
Continuity Resistance	0.0 Ω - 1999 Ω
Dimensions	220 x 103 x 55 mm
Operating Temperature	-10°C to 50°C
Storage Temperature	-20°C to +60°C
Safety Standards	EN 61557
Loop Resistance Accuracy	±(5% + 3 digits)