Siemens SIMATIC User Manual

Other signal modules
7.4 Position decoder module SM 338; POS-INPUT; (6ES7338-4BC01-0AB0)
S7-300 Module data
Manual, 06/2017, A5E00105505-AJ
501
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.

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)