(1)
Operating error
Resistance of rods R
and R
H
Measurement range
Resolution
Intrinsic error
(1)
with spurious voltages ≤ 60V
signal frequency > 0.2 x measurement frequency.
4.4 COUPLING MEASUREMENT (3-pole measurement)
This measurement is performed on the 3-pole position of the switch and in MANUAL mode only.
The earth coupling value is calculated using 3 successive earth resistance measurements :
- the first 2 measurements are two 3-pole classic measurements (see §4.3); these give
results R
and R
,
1
2
- the third measurement is a 2-pole measurement which gives the result R
Once the 3 measurements have been performed, the instrument automatically calculates the coupling
resistance R
as follows :
C
As well as the coupling factors C
and the resistances R
and R
A
4.4.1
CONNECTIONS :
See above, §4.3.1.
4.4.2
PRE-MEASUREMENT SETTINGS
Configure the instrument for an EARTH COUPLING measurement:
- set the rotary switch to the 3-pole position,
CONFIG
CONFIG
CONFIG
- using the
key, select the MANUAL mode, then EARTH COUPLING.
DISTANCE
DISTANCE
CONFIG
CONFIG
CONFIG
Once again, using the
DISTANCE
DISTANCE
- select the measurement frequency (41, 55, 92, 110, 119, 128, 476 Hz, or USr
- select the voltage applied (16 or 32 V).
(1)
The frequency "USr" is defined by the user for between 41 and 512 Hz using the
R
and/or R
≤ 20kΩ
H
S
R
/R
and/or R
/R
H
E
S
Measurement freq. btw 41 and 300 Hz
R
and/or R
≤ 100kΩ
H
S
R
/R
and/or R
/R
H
E
S
Measurement freq. btw 41 and 150 Hz
R
and/or R
≤ 20kΩ
H
S
R
/R
and/or R
/R
H
E
S
Measurement freq. btw 300 and 500 Hz
S
0.01 – 9.99Ω 10.0 – 99.9Ω
0.01Ω
0.1Ω
± (10% + 2pt) at 128 Hz
and difference between measurement frequency and spurious
peak
R
= (R
+ R
- R
C
1
2
1-2
and C
defined by :
1
2
C
= R
/ R
and
C
1
C
1
defined by :
B
R
= R
- R
and R
A
1
C
B
key, you can then:
46
± (5% + 2pt)
≤ 5000
E
± (20% + 3pt)
≤ 20000
E
± (10% + 1pt)
≤ 1000
E
100 - 999Ω 1.00 – 9.99kΩ 10 – 99.9kΩ
1Ω
10Ω
.
1-2
) / 2
= R
/ R
2
C
2
= R
- R
2
C
100Ω
(1)
),
keys.