
GroundTest
M71
EN – 20
6. TECHNICAL SPECIFICATIONS
6.1. TECHNICAL
FEATURES
Accuracy is calculated as [% rdg + (dgt number) * resolution] at 23°C ± 5°C,< 80%HR
CAUTION
Under modes EARTH-2W and EARTH-3W the instrument displays the
symbol of warning
whenever:
It is working under critical conditions, such as in the presence of input
voltages
It cannot grant the uncertainty of measurement lower than 30% of
reading, according to IEC/EN61557-1
Earth Resistance measurement
Range Resolution
Accuracy
Disturbance
3Vrms
3Vrms<Disturbance<6Vrms
AUTO mode triggered
0.01
19.99
0.01
(2%rdg + 3dgt)
(4%rdg + 10dgt)
20.0
199.9
0.1
200
1999
1
2.00
19.99k
0.01k
20.0
49.9k
0.1k
(3rdg + 3dgt)
(6%rdg + 10dgt)
Measurement frequency
110Hz
1Hz
Test current
12mA~
Open circuit voltage
25Vrms
Resistance values of the voltmetric (Rp) and ampermetric probes (Rc) always meet the following conditions:
If R
A
10
Rc, Rp
1k
If 10
< R
A
500
Rc, Rp
100 * R
A
If R
A
> 500
Rc, Rp
50k
Disturbance Voltage measurement
Range (V)
Resolution (V)
Accuracy
0.0
99.9
0.1
(2%rdg + 2dgt)
100
299
1