The 7I37-COM is a version of the 7I37 with a common input reference and a common output power source. The 7I37-COM can simplify I/O wiring when individually isolated inputs and outputs are not required. The 7I37COM has 16 isolated inputs and 8 isolated outputs like the standard 7I37 but the inputs share a common ground or minus input reference, and the outputs share a common power source. The outputs drive ground referred loads (so call PNP output type).
The 7I37-COM's I/O specifications are the same as the standard 7I37 but the 7I37-COM adds output freewheeling diodes. Due to the output power commoning, AC loads cannot be driven by the 7I37-COM.