Table of Contents
Advertisement
mΩ
E
EARTH
EARTH COUPLING : coupling measurement between two earth sockets
ES
H
I-Act
(1)
I
ES
I
H-E
I
SEL
NOISE
R
R+
R-
R-Act
(1)
R
1
R
2
R
1-2
R
A
R
b
R
C
R
E
R
H
70
: measurement of low resistance /continuity
: terminal E (X) - earth socket; current measurement return
terminal
: earth measurement (3 or 4 poles)
: ES (Xv) terminal (measurement potential socket for
calculating earth resistance)
: H (Z) terminal (measurement current injection terminal)
: external current circulating at present between the instrument
terminals
: current measured by the clamp connected to the ES terminal
(selective earth measurement with clamp)
: measurement current circulating between the H and E
terminals
: current measured via the GroundFlex
(selective earth measurement with GroundFlex
: indicates the presence of external interference causing
misrepresentation of the earth or resistivity measurement
: average resistance calculated from R+ and R-
: resistance measured with a positive current circulation from
terminal H to E
: resistance measured with a negative current circulation from
terminal H to E
: resistance currently calculated from values U-Act and I-Act
: first value measured to calculate the coupling between 2 earth
sockets (R
= R
1
: second value measured to calculate the coupling between 2
earth sockets (R
: third value measured to calculate the coupling between 2
earth sockets (R
: first earth value calculated (R
: second earth value calculated (R
: coupling resistance between earths R
– R
) / 2)
1-2
: earth resistance connected to terminal E
: resistance of the stake connected to terminal H
+ R
)
A
C
= R
+ R
)
2
b
C
= R
+ R
)
1-2
A
b
= R
A
Ground Resistance Tester Model 6472
Adapter Model 6474
®
)
®
- R
)
1
C
= R
- R
)
b
1
C
and R
(R
A
b
= (R
+ R
c
1
2
Advertisement
Table of Contents
