METREL MI 3125 User Manual

MI 3125 InstaltestCOMBO Compensation of test leads resistance
25
5 Measurements
5.1 Compensation of test leads resistance
This chapter describes how to compensate the test leads resistance in R LOWΩ, and
SOCKET test. Compensation is required to eliminate the influence of test leads
resistance and the internal resistances of the instrument on the measured resistance.
The symbol is displayed if the compensation was carried out successfully.
Circuits for compensating the resistance of test leads
N
/
L
2
L
/
L
1
L
/
L
1
P
E
/
L
3
N
/
L
2
P
E
/
L
3
p
rolongation lead
Figure 5.1: Shorted test leads
Compensation of test leads resistance procedure
 Select R LOWΩ, or SOCKET test function.
 Connect test cable to the instrument and short the test leads together (see figure
5.1).
 Press TEST to perform resistance measurement.
 Press the CAL key to compensate leads resistance.
Figure 5.2: Results with old calibration
values
Figure 5.3: Results with new calibration
values
Note:
 The highest value for lead compensation is 5 Ω. If the resistance is higher the
compensation value is set back to default value.
is displayed if no calibration value is stored.

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)