K-Patents PR-21-S - Manual (Page 59)

6 Configuration and calibration 53
Note: NAMUR is an international association of users of automation in process
industries. The association recommendation NE 43 promotes a standardization
of the signal level for failure information. The goal of NE 43 is to set a basis for
proactively using transmitter failure signals in process control strategies. Using
these failure signals, instrument faults are separated from process measurements.
NAMUR NE 43 uses the 3.8 to 20.5 mA signal range for measurement information,
with ≥21 mA or ≤3.6 mA to indicate diagnostic failures (see figure 6.11). With
that information, it is easier to detect a failure condition on a refractometer, for
example, it clearly tells you whether you have an empty pipe or a failed instrument.
0 3.6
3.8
4 20
20.5
21
mA
failure OK
Measurement Data
failure
Figure 6.11 Default mA output values
−
6 MANUAL SET allows you to set different output values to check the output signal.
Press the BACK key to return normal output function.
Note: If you want to ’turn off’ the mA output, select NOT DEFINED in the Source menu.