Loss Of Echo (Loe) - Siemens HydroRanger 200 HMI Operating Instructions Manual

You can also set the mA output to report when the device is in an error condition and the
fail-safe timer has expired. By default, the reported value depends on the device type. A
standard device reports the last valid reading, and a NAMUR NE43 compliant device
reports the user-defined value for

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.
If the LOE condition persists beyond the time limit set in
the Service Required icon, and the text region displays the fault code 0 and the text LOE.
If two faults are present at the same time, the device status indicator and text for the
highest priority fault will display. For example, if both Loss of Echo and Broken cable
faults are present, the Broken cable fault will display.
1 Broken cable
Fail-safe Mode
The purpose of the Fail-safe setting is to put the process into a safe mode of operation in
the event of a fault or failure. The value to be reported in the event of a fault (as displayed
2.5.9. Milliamp Output
in
same response as an unsafe level.
2.4.2. LOE Timer
determines the length of time a Loss of Echo (LOE) condition will persist
before a fail-safe state is activated. The default setting is 100 seconds.
2.4.5. Material Level
2.4.2. LOE Timer
reported when
Upon receiving a reliable echo, the loss of echo condition is aborted, the Maintenance
Required icon and error message are cleared, and the mA output returns to the current
material level. [The Primary reding on the HMI display will show dashes (– – – –) when a
fault that causes fail-safe is present, and will return to the current reading when the fault
is cleared.]
A5E36281317
2.4.9. mA Fail-safe Value
) is selected so that a loss of power or loss of signal triggers the
determines the mA value (corresponding to the selected PV) to be
expires.
HydroRanger 200 HMI – OPERATING INSTRUCTIONS
(3.58 mA by default).
2.4.2. LOE Timer
, the LCD displays
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