Siemens SIMATIC ET 200M Operating Instructions Manual page 248

Compatibilities between the IM 153-x
A.3 RC Network with 1 MΩ for Configuration with ungrounded reference potential
See also
Configuration of an ET 200M with ungrounded reference potential (Page 54)
RC Network with 1 MΩ for Configuration with ungrounded reference potential (Page 246)
Redundancy with IM 153-2 (Page 162)
What is Isochronous? (Page 168)
A.3 RC Network with 1 MΩ for Configuration with ungrounded reference
potential
The principle of the ET 200M structure with ungrounded reference potential can be found in
chapter "Configuration of an ET 200M with ungrounded reference potential (Page 54)".
IM 153-x with a resistance of 1 MΩ
The following IM 153-x have in the RC network a resistance of 1 MΩ:
● IM 153-1
● IM 153-2
①
The following applies for this IM 153-x:
Maximum 18 nodes can be operated on the PROFIBUS DP in an unearthed structure on a
power supply.
With more than 18 nodes you must use an additional power supply.
Subsequent Versions
All later versions have a resistance of 10 MΩ in the RC network.
246
up to and including 153-1AA02, version 07
up to and including 153-1AA82, version 06
up to and including 153-2AA01, version 02
Ground bus
1
Operating Instructions, 12/2008, EWA-4NEB780600602-08
ET 200M