6
6-3
C7-626 / C7-626 DP Control Systems
C79000-G7076-C626-01
The isolated transducers are not connected with the local ground potential.
They can be operated free of potential. Local conditions or interference can
cause potential differences V
CM
(static or dynamic) to occur between the
measuring lines M of the input channels and the reference point of the
measuring circuit M
ANA
. However, this potential difference must not exceed
the permissible value. Where it is possible that the permissible value for V
CM
might be exceeded, or where you cannot determine the difference in potential
accurately, you must connect AIx-M to M
ANA
.
Figure 6-1 shows the principle of connecting isolated transducers to an
isolated analog input module.
Isolated
transducers
AIx-X
M
ANA
C7 CPU
V
CM
ADC
M
V
ISO
Lo
gic
AIx-M
AIx-X
AIx-M
L+
C7
Ground bus
Figure 6-1
Connecting Isolated Transducers to an Isolated Analog Input Module
The non-isolated transducers are connected on-site with the ground potential.
Depending on local conditions or interference, potential differences (static or
dynamic) can occur between the locally distributed measuring points. To
prevent these potential differences, you must provide equipotential bonding
conductors between the measured value points.
In addition, potential differences V
CM
(static or dynamic) can arise between
the measuring lines AIx-M of the input channels and the reference point of
the measuring circuit M
ANA
. However, these potential differences must not
exceed the permitted value. Where it is possible that the permissible value
for V
CM
might be exceeded, or where you cannot determine the difference in
potential accurately, you must connect AIx-M to M
ANA
.
Figure 6-2 shows the principle of connecting non-isolated transducers to an
isolated analog input module.
Isolated
Transducers
Non-Isolated
Transducers
C7 Analog Input/Output
Содержание SIMATIC C7-626
Страница 18: ...1 1 6 C7 626 C7 626 DP Control Systems C79000 G7076 C626 01 Product Overview ...
Страница 72: ...3 3 26 C7 626 C7 626 DP Control Systems C79000 G7076 C626 01 Configuring MPI Networks and PROFIBUS DP Networks ...
Страница 78: ...4 4 6 C7 626 C7 626 DP Control Systems C79000 G7076 C626 01 Connecting a Programming Device PC to a C7 ...
Страница 122: ...A A 8 C7 626 C7 626 DP Control Systems C79000 G7076 C626 01 General Technical Specifications ...
Страница 138: ...Glossary 10 C7 626 C7 626 DP Control Systems C79000 G7076 C626 01 Glossary ...
Страница 142: ...Index 4 C7 626 C7 626 DP Control Systems C79000 G7076 C626 01 Index ...