NE 43 has been revised

The NAMUR Recommendation NE 43 has been revised and may now be obtained from the NAMUR Office.

The change compared to the previous edition of NE 43 (2003-02-03) mainly concern the introduction of a safety margin for signal detection in control systems and the device behavior during initialization.

Abstract NE 43 ‘Standardization of the Signal Level for the Failure Information of Digital Transmitters’
(Edition: 2021-07-26)

The purpose of this recommendation is to standardize the signal level of the failure information in the analog current signal. This creates the basis for a standardized use of the failure signal in automation systems.

Additional information outside of the actual measurement information, is already widespread today due to the use of microprocessors in field devices. A device failure information has been defined as an indispensable part of the status signals of a sensor system.

The use of failure information in digital transmitters with analog output signal provides two major advantages for process control engineering:

• Faults in the measuring system are thus signaled at an early stage, so that the effects can be limited in information-processing systems by means of failure strategies.
• In addition, maintenance strategies can be implemented with the aim of increasing the efficiency of PCT maintenance.