Connection Of Non-Isolated Sensors To An Equipotentially Bonded Analog Input Module - Siemens SIMATIC ET 200S Manual

Analog Electronic Modules
Non-isolated sensors
The non-isolated sensors are locally connected to the ground potential. M
be connected to the ground potential. Depending on local conditions or
interference potential differences U
between the locally distributed measuring points.
If the permitted value for U
installed between the sensor locations.
Figure 12-2 shows the general connection of non-isolated sensors to an
equipotentially bonded analog input module.
Non-isolated
sensors
Figure 12-2
Operating 4-wire measuring transducers (MU) at external power supply
If the MU output and power supply is isolated, the MU can be connected to the 2AI
I 4WIRE without any additional connections.
If the MU output and power supply is not isolated, the MU can be connected to the
2AI I 4WIRE only if the power supply voltages have the same reference potentials
connections.
If the interference is increased, we recommend a connection between M-- and
M to the terminal module of the 2AI I 4WIRE.
ana
12-20
is exceeded, equipotential bonding lines must be
CM
U
CM
Equipotential
bonding
U
cable
Grounding busbar
Connection of non-isolated sensors to an equipotentially bonded analog input
module.
(static or dynamic) may be encountered
CM
M+
:
M--
M+ ADC
: M --
M
ANA
ISO
ANA
L+
M
Backplane bus
ET 200S Distributed I/O System
EWA-4NEB 780602402-12
must