User's Manual

Table Of Contents
Appendix A: Technical reference
A.3 Analog Output
SITRANS LR250 (HART)
226 Operating Instructions, 01/2014, A5E32220602-AB
A.3.2
Current Output Function
Current Output Function (2.6.1.)
controls the mA output and applies any relevant scaling. By
default it is set to
Level
. Other options are Space, Distance, and Volume. (The device can carry
out a volume calculation only after a vessel shape has been specified.)
When a volume application type is chosen, Sensor Mode remains as
Level
and the mA Output is
automatically converted to
Volume
.
To view the mA reading in the secondary region of the LCD, press on the handheld
programmer.
A.3.3
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 (2.8.6.1.)
describes the quality of an echo. Higher values represent higher quality.
Echo Threshold (2.8.4.3.)
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
LOE Timer (2.5.2.)
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.