Current Output Function; Loss Of Echo (Loe) - Siemens SITRANS LR560 Operating Instructions Manual

Technical reference
A.4 Analog output
You also have the option to put the device out of service, in which case the device defaults to
Fail-safe mode, and the reported level depends on the device type. A standard device reports
the last valid reading, and a NAMUR NE 43-compliant device reports the user-defined value for
Material Level (3.58 mA by default).
①
③
⑤
A.4.2

Current Output Function

Current Output Function (2.6.1.) controls the mA output and applies any relevant scaling. By
default it is set to Distance. Other options are Space and Level.
To view the mA reading in the secondary region of the LCD, press
programmer.
A.4.3

Loss of Echo (LOE)

A loss of echo (LOE) occurs when the calculated measurement is judged to be unreliable
because the echo confidence value has dropped below the echo confidence threshold.
CONFIDENCE (2.7.6.1) (Page 126) describes the quality of an echo. Higher values represent
higher quality.
ECHO THRESHOLD (2.7.3.2) (Page 122) defines the minimum confidence value required for an
echo to be accepted as valid and evaluated.
If the LOE condition persists beyond the time limit set in TIMER (2.5.2.) (Page 116) the LCD
displays the Service Required icon, and the text region displays the fault code S: 0 and the text
LOE.
If two faults are present at the same time, the fault code, error text, and error icon for each fault
are displayed alternately. For example, Loss of Echo and Fail-safe.
188
Level
sensor reference point
20 mA, 100%
low calibration point
Space
②
high calibration point
④ 4 mA, 0%
Operating Instructions, 06/2017, A5E34647946-AD
Distance
on the handheld
SITRANS LR560 (mA/HART)