Siemens SIRIUS 3SK1 Manual page 97

Maximum system configuration when supplying with 24 V DC using the 3SK1230 power supply
When using the 3SK1230 power supply, the maximum system configuration can be
calculated as follows:
Up to 10 "system units" can be connected to a 3SK1230 power supply.
Individual devices occupy a different number of system units.
Note
With this configuration too, up to 5 expansions are permitted to the left of the basic unit and 5
expansions are permitted on the right.
Device
Input expansion 3SK1220
Power supply 3SK1230
Basic units 3SK1
Output expansion 3SK1211
Output expansion 3SK1213
Example 1x 3SK1230 power supply; 5 x 3SK1220 input expansion; 1 x 3SK1 basic unit; 2 x
3SK121 output expansion
110 ... 240 V AC
3SK1 safety relays
Manual, 04/2013, A5E02526190021A/RS-AA/01
L1 N
1 1 1
Input
expansions
1 1 0 2
Output
expansions
System configuration
6.1 General information
System unit
2
1
0
0
2
2
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