Siemens 6ES7-222-1HF21-0XA0 Output Module

Siemens 6ES7-222-1HF21-0XA0 Output Module is an eight-point digital relay output module (EM222) designed for use with the SIMATIC S7-200 family. It provides eight relay contacts that can switch external loads, enabling galvanic isolation between the PLC and field devices. Each relay output is rated to handle up to 2 A, with a maximum switching voltage of 250 V AC, making it suitable for controlling pumps, solenoids, lights, and other line-powered equipment. The module's control side is powered by a 21–28 V DC input, compatible with standard 24 V DC control signals from S7-200 I/O. It plugs into the S7-200 expansion bus and can be mounted in compatible I/O racks to extend discrete output capability for compact automation tasks. The 6ES7-222-1HF21-0XA0 designation identifies this EM222 8-point relay module, aligning with Siemens' 2nd generation S7-200 modular I/O catalog. Typical field applications include machine control, process sequencing, and appliance control where robust relay switching and electrical isolation are required, while preserving low-voltage logic control from the PLC. This output module is commonly used in legacy Siemens systems and can be found in automation installations that rely on the EM222 family for reliable, discrete control of higher-power loads.