Siemens SIMATIC User Manual

Principles of analog value processing
4.2 Wiring and connecting transducers to analog inputs
S7-300 Module data
Manual, 06/2017, A5E00105505-AJ
241
Wiring and connecting electrically isolated transducers to a non-isolated AI
The CPU / IM 153 can be operated in grounded mode or ungrounded mode.
Figure 4-2 Wiring and connecting electrically isolated transducers to a non-isolated AI
Note
Do not interconnect M
- with M
ANA
when wiring and connecting 2-wire transducers and
resistance transducers. An equalization current develops at the interconnection of M
- with
M
ANA
and corrupts the measured value. This also applies to unused inputs which are
programmed accordingly.
4.2.2 Wiring non-isolated transducers
Non-isolated transducer
Non-isolated transducers are interconnected with local ground potential. Always interconnect
M
ANA
with local ground when using non-isolated transducers.
Local conditions or interference may cause potential differences CMV (static or dynamic)
between locally distributed measuring points. If the maximum CMV value is exceeded,
interconnect the measuring points by means of equipotential conductors.

Siemens SIMATIC Specifications

General

Product type designation	SIMATIC
CPU	Varies by model
Memory	Varies by model
Input/Output	Varies by model
Communication	Varies by model
Programming Language	STEP 7
Operating Temperature	0°C to 60°C (varies by model)
Protection Class	IP20
Category	Programmable Logic Controller (PLC)