Siemens 6NH9804-1CBThe Siemens 6NH9804 1CB is an essential electronic module engineered for industrial automation, particularly within process control and monitoring applications. Designed for compatibility with Siemens SIMATIC S7 200 and S7 300 programmable logic controllers (PLCs), this digital input module features four versatile inputs that can detect both normally open and normally closed contacts. It operates within a voltage range of 24 V DC and supports an input