Siemens 6ES7321-1BL00-0AA0 32-Point Input Module

Siemens 6ES7321-1BL00-0AA0 SM321 Digital Input Module is a 32-point input module for SIMATIC S7-300 PLC automation systems, designed to receive 24 V DC signals from sensors, switches and field devices. It provides 32 DC inputs with a 20.4–28.8 V DC range, has galvanically isolated inputs (grouped), and uses a 40-pin front connector for reliable field cabling. The module supports IEC 61131‑compliant DC inputs, offers a response time of approximately 1.2–4.8 ms, and consumes about 6.5 W of power; it mounts rack-style on the S7-300 backplane and is part of the SIMATIC SM321 family. Its 32-channel density suits industrial automation tasks such as manufacturing lines, packaging systems, conveyor automation, and process control where fast digital signal acquisition is essential. Common replacements include Siemens 6ES7321-1BH02-0AA0, 6ES7321-1BL00-0AB0, and 6ES7221-1BF32-0XB0.