Wiring And Block Diagrams - Siemens SIMATIC Manual

7.4.2

Wiring and block diagrams

Wiring and block diagrams
①
Error LED - red
②
Connection to CPU ground
③
Twisted-pair cables
Wiring rules
Important rules to observe wiring the module:
● Ground of the encoder supply is connected to CPU ground potential. Thus, establish a
low impedance connection between pin 2 of SM 338 (M) and CPU ground.
● Always use shielded twisted-pair cable to wire encoder signals (pins 3 to 14.) Connect
both ends of the shielding.
Use the shield connection element to terminate the shielding on SM 338 (order number
6ES7390-5AA00-0AA0).
● Connect an external power supply if the maximum output current (900 mA) of the encoder
supply is exceeded.
S7-300 Module data
Manual, 06/2017, A5E00105505-AJ
7.4 Position decoder module SM 338; POS-INPUT; (6ES7338-4BC01-0AB0)
Other signal modules
501