The invention relates to a connection module for field devices in the explosion-protected area, having a housing with a plurality of controller-end terminals to connect to at least one input/output module and with field-end terminals to connect to the field devices. The connection module is characterized in that different resistors are present in the housing to provide intrinsically safe pairs of field-end terminals with different characteristic values, said resistors being hardwired in the housing to different field-end terminals and/or controller-end terminals.