Siemens Simatic M7-400 Reference Manual page 163

4.11 Digital Input Module SM 421; DI 16
(6ES7421-5EH00-0AA0)
Characteristics
The SM 421; DI 16
• 16 inputs, isolated
• 120 VAC rated input voltage
• Suitable for switches and two-wire proximity switches
(BEROs, IEC 61131; type 2)
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
120 VAC has the following features:
Digital Modules
120 VAC
;
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