Technical Features - Amprobe GP-2A Manual De Uso

9.2 Technical Features

3- and 2-wire earth resistance measurement - EARTH 3W and EARTH 2W
Range [Ω](**)
0.01 ÷ 19.99
20.0 ÷ 199.9
200 ÷ 1999
2.00 ÷ 19.99k
20.0 ÷ 49.9k
Operating uncertainty (according to EN61557)
Fiducial
Read.o
Value
[Ω] [Ω]
17.986 18.00
180.03 180.1
1495.4 1492
18.029k 18.08k
46.76k 46.9k
For the meanings of the items see Par. 9.1.
Ground resistivity measurement - r (@ d=1m, 3ft)
Range (**)
Reading [Ωm]
0.06 ÷ 19.99
20.0 ÷ 199.9
200 ÷ 1999
2.00 ÷ 19.99k
20.0 ÷ 199.9k
200 ÷ 314k
Note:
(*) If R > 1200 + 100 R
P
carries out the test, the accuracy of the instrument is (10% reading) where:
R = resistance of the voltage circuit ES - S
P
R = resistance of the current circuit E - H
C
R = measured earth resistance
E
(**) Automatic selection of the range
Measuring frequency
Test current
Open loop voltage
Disturbance voltage on ampere and volt circuits: the measurement is taken with the stated
accuracy if the interfering voltage is ≤3V, while for interfering voltages ranging from > 3V and
≤9V, the accuracy decreases progressively; with an interfering voltage equal to 9V the instrument
does not perform the test.
Intrinsic
Uncertainty
E1
A
[Ω] [Ω]
0.014 0.01
0.07 0.1
3.4 0
0.051k 0.00k
0.14k 0.0k
Measure [Ωm]
0.50 ÷ 19.99
20.0 ÷ 199.9
200 ÷ 1999
2.00 ÷ 19.99k
20.0 ÷ 199.9k
200 ÷ 314k
and/or R > 1200 + 100 R
X C
77.5 ± 1Hz
≤12mA
≤25Vrms
Resolution [Ω]
0.01
0.1
1
0.01k
0.1k
Influence quantity
E2 E3
[Ω] [Ω]
0.00 0.05
0.0 0.5
1 4
0.00k 0.07k
0.0k 0.2k
Resolution [Ωm]
0.01
0.1
1
0.01k
0.1k
1k
, R > 50k and/or R
X P
22
Operating uncertainty
± (2.5% reading + 2 digits)
uncertainty B
E4 E5
[Ω] [Ω]
0.04 0.03 0.096
0.4 0.3 0.82
1 3
0.01k 0.12k 0.21k
0.0k 0.4k 0.66k
Uncertainty (*)
± (2.5% reading + 2 digits)
> 50k and the instrument
C
operating
[Ω] [%]
0.53
0.46
9.3 0.62
1.17
1.40