Beckhoff EL3101, Документация

Страница: 83 / 229

Commissioning
EL31xx-00xx 83 Version: 5.9
5 Commissioning
5.1 NAMUR basic information
The abbreviation of NAMUR, “User Association of Automation Technology in Process Industries” identifies
an international association for users of automation technology that considers the interests related to
standardization, devices and measurement control (or similar) of the Process Industries as its major task. In
this role, the NAMUR releases the so called NE (proposed standards), each numbered continuously.
Information with regard to the implementation of this recommendation in Beckhoff products are specified in
sections “Technical data” and “Process data” of this documentation.
Analog measured values
The analog output value of a sensor that can be measured among other things as a certain current value
represents the measurement information (M).
By means of NAMUR NE43 a recommendation – irrespective of the sensor manufacturer – for standardized
failure information (A) is defined in addition to the measurement information (e.g. malfunction of a
measurement converter, error in connective wires, failure of an auxiliary energy etc.). The failure information
states that there is an error in the measuring system. This concerns the analog output signal of sensors in a
current loop and therefore in the form of a current value. A current value lying outside of the limits defined by
NAMUR is defined as invalid and is thus interpreted as failure information. The following diagram illustrates
this:
Fig. 63: Representation of the definitions from NAMUR recommendation NE43, version 03/02/2003