METREL MI 3290 - Earth Measurements [Ze and Re]

MI 3290 Earth Analyser Tests and Measurements
70
Figure 11.6: Examples of Visual Test results
11.2 Earth Measurements [Ze and Re]
Result of Earth measurement is one of the most important parameters for protection against
electric shock. Main installation earthing arrangements, lightning systems, local earthings,
soil resistivity, etc. can be verified with the Earth tester.
The MI 3290 Earth Analyser is able to carry out Earth measurement using different methods.
The appropriate one is selected by the operator depending on the particular earthing system
to be tested.
Earth
Measurement
Test
Mode
Graph
LF
HF
Filter
Test
Voltage
Impedance
Resistance
Ze
Re
2 – pole
single
sweep
Ze (f)
55 Hz
15 kHz
FFT
20/40 V
3 – pole
single
sweep
Ze (f)
55 Hz
15 kHz
FFT
20/40 V
4 – pole
single
sweep
Ze (f)
55 Hz
15 kHz
FFT
20/40 V
Zsel
/
Selective
(Iron Clamp)
single
sweep
Zsel (f)
55 Hz
1,50 kHz
FFT
40 V
Ze
2 Clamps
cont.
/
/
82 Hz
329 Hz
FFT
40 V
Ze
Re
HF Earth
Resistance (25 kHz)
single
/
/
/
25 kHz
FFT
40 V
Ztot
/
Selective
(Flex Clamps 1 – 4)
single
sweep
Ztot (f)
Zsel1-4 (f)
55 Hz
6,59 kHz
FFT
40 V
/
Passive
(Flex Clamps 1 – 4)
cont.
/
/
45 Hz
150 Hz
FFT
/
Table 11.7: Available Earth measurements in the MI 3290