Siemens 6Es5420-4Ua12 32-Channel Digital Input Module

The Siemens SIMATIC 6ES5420-4UA12 is a 32-channel digital input module for the SIMATIC S5 PLC platform, designed to interface 24 VDC input signals from sensors, switches, and other field devices in industrial automation. This compact U-version DI 420 module mounts in a rack and supports non-isolated 24 VDC inputs, with a front connector that uses screw or crimp terminals depending on the accessory, and it is compatible with S5-135U and S5-155U systems, with S5-115U operation possible via adapter casing 6ES5491-0LB11. Weighing about 0.45 kg and rated for 0°C to +60°C, it is listed as a spare part / legacy module; common replacements include 6ES5420-4UA13 and 6ES5420-4UA11.