Method, communication module and system for transmitting diagnosis data of a field device in an installation for process automation

A method for transmitting diagnosis data of a field device in an installation for process automation, wherein the field device has a communications link to a superordinate unit via a communications loop, comprising:

• connecting a communications module to the communications loop in parallel with the field device;
• capturing with a transducer unit in the communications module an electrical and/or physical variable and converting the electrical and/or physical variable into electrical energy;
• storing the converted electrical energy in an energy storage unit of the communications module up to a predetermined limit value;
• polling the diagnosis data of the field device using a communication command of the communications module;
• receiving the diagnosis data of the field device by the communications module via a communication command sent by the field device;
• and
• wirelessly transmitting the polled diagnosis data from the communications module to a reception unit as soon as the electrical energy stored in the energy storage unit reaches or exceeds the predetermined limit value and/or if the communications module receives a command for polling or transmitting.

A communications module, comprising:

• a transducer unit embodied to convert an electrical and/or a physical variable into electrical energy;
• an energy storage unit connected with the transducer unit and embodied to store the converted electrical energy;
• a polling unit configured to poll diagnosis data of a field device;
• and
• a transmission unit embodied to wirelessly transmit the polled diagnosis data to a reception unit.

A system for transmitting diagnosis data from a field device in an installation for process automation, comprising:

• a superordinate unit in communication with the field device via a communications loop;
• a communications module connected to the communication loop in parallel with the field device, the communications module including:
• a transducer unit embodied to capture an electrical and/or physical variable and convert the electrical and/or physical variable into electrical energy;
• an energy storage unit connected downstream of the transducer unit and embodied to store electrical energy from the transducer unit;
• a polling unit;
• and
• a transmission unit;
• and
• a reception unit,
• wherein the communications module is configured to poll diagnosis data from the field device and transmit the polled diagnosis data to the reception unit via a wireless radio link as soon as a predetermined limit value of stored energy is reached in the energy storage unit of the communications module or when the communications module receives a command for polling or transmitting.