Analog Modules
5-45
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
Non-Isolated Sensors
The non-isolated sensors are connected with the local ground potential (local
ground). When using non-isolated sensors, you must connect MANA to chassis
ground.
Connecting Non-Isolated Sensors
Caused by local conditions or interference, potential differences UCM (static or
dynamic) can occur between the locally distributed individual measuring points. If
the potential difference UCM exceeds the permissible value, you must provide
equipotential bonding conductors between the measuring points.
M+
M–
UISO
M+
M–
MANA
Chassis ground
Non-isolated
sensors
UCM
Equipotential
bonding conductor
Figure 5-8 Connecting Non-Isolated Sensors to an Isolated AI
Note
Do not use non-isolated two-wire transmitters and non-isolated resistance sensors!