71
6.3.4. 3P EARTH MEASUREMENT
Quantities of influence
Limits of the range of use
Variation of the measurement
Typical
Maximum
Temperature
-10 … + 55 °C
1 %/10 °C ± 1 ct
2 %/10 °C + 2 ct
Relative humidity
10 … 85 % RH at 45°C
2 %
3 % + 2 ct
Supply voltage
8.4 … 10 V
0.25% or 1 ct
1% + 1 ct
Voltage in series in the voltage measure-
ment loop (S-E)
Fundamental = 16.6/50/60Hz + odd
harmonics
15 V (R
E
≤
40
W
)
25 V (R
E
> 40
W
)
0.5% or 10 ct
2% + 50 ct
2% + 2 ct
Voltage in series in the current injection
loop (H-E)
Fundamental = 16.6/50/60Hz + odd
harmonics
15 V (R
E
≤
40
W
)
25 V (R
E
> 40
W
)
0.5% or 10 ct
2% + 50 ct
2% + 2 ct
Current loop rod resistance (R
H
)
0 to 15 k
W
0.3%
1% + 2 ct
Voltage loop rod resistance (R
S
)
0 to 15 k
W
0.3%
1% + 2 ct
6.3.5. CURRENT MEASUREMENT
Quantities of influence
Limits of the range of use
Variation of the measurement
Typical
Maximum
Temperature
-10 … + 55 °C
1 %/10 °C ± 1 ct
2 %/10 °C + 2 ct
Relative humidity
10 … 85 % RH at 45°C
2 %
3 % + 2 ct
Supply voltage
8.4 … 10 V
0.1% or 2 ct
0.5% + 2 ct
Frequency
15.8 … 45 Hz
45 … 450 Hz
1%
0.5%
1% + 1 ct
1.5% + 1 ct
50/60Hz series mode rejection in AC
0 … 500 V
ac
50 dB
40 dB
6.3.6. EARTH MEASUREMENT ON LIVE CIRCUIT, LOOP AND SELECTIVE EARTH
Quantities of influence
Limits of the range of use
Variation of the measurement
Typical
Maximum
Temperature
-10 … + 55 °C
1 %/10 °C ± 1 ct
2 %/10 °C + 2 ct
Relative humidity
10 … 85 % RH at 45°C
2 %
3 % + 2 ct
Supply voltage
8.4 … 10 V
0.5% or 2 ct
2% + 2 ct
Network frequency of the installation
tested
99 to 101% of the nominal
frequency
0.1% or 1 ct
0.1% + 1 ct
Network voltage of the installation tested
85 to 110% of the nominal
voltage
0.1% or 1 ct
0.1% + 1 ct
Phase difference between the internal load
and the measured impedance or induct-
ance of the measured impedance or L/R
ratio of the measured impedance
0 …20°
or 0 … 400 mH
or 0 … 500 ms
1%/10°
1%/10°
Resistance in series with the voltage probe
(earth on live circuit only)
0 … 15 k
W
Negligible
(taken into account in the
intrinsic uncertainty)
Negligible
(taken into account in the
intrinsic uncertainty)
Contact voltage (U
C
)
0 … 50 V
Negligible
(taken into account in the
intrinsic uncertainty)
Negligible
(taken into account in the
intrinsic uncertainty)
