Siemens SITRANS LUT400 Series Operating Instructions Manual page 456

2.3.2. Empty Rate per Minute
Defines the maximum rate at which the reported level is allowed to decrease.
Adjusts the SITRANS LUT400 response to decreases in the actual material
level.
Values
Enter a value slightly greater than the vessel's maximum emptying rate, in units
per minute.
2.3.3. Damping Filter
Use this to stabilize the reported level (displayed and analog output), due to lev-
el fluctuations (such as a rippling or splashing liquid surface), defined in sec-
onds.
Values
2.4. Fail-Safe
The fail-safe parameters ensure that the devices controlled by the SITRANS LUT400
default to an appropriate state when a valid level reading is not available. The PV
region on LUI will display dashes (– – – – – – –) until the fail-safe fault has been
cleared. (See General Fault Codes on page 233 for a list of faults that will cause fail-
safe.)
Note: When a Loss of Echo occurs Material Level (2.4.1.) determines the material
level to be reported when the Fail-safe timer expires. See Loss of Echo (LOE) on
page 263 for more detail.
2.4.1. Material Level
Note: The default is a factory setting and depends whether or not your device
was ordered as NAMUR NE43-compliant for Fail-safe.
Defines the mA output to use (shown in Current Output Value) when the Fail-
safe Timer expires and the device is still in an error condition.
Options
Default
A5E33329501 SITRANS LUT400 (HART) – OPERATING INSTRUCTIONS
Range: 0.000 to 99999.000 m/min
Default: 0.100 m/min
Range: 0.0 to 7200.0
Default: 100.0
HI 20.0 mA (max. mA Limit)
LO 4.0 mA (min. mA Limit)
HOLD Last valid reading
User-selected value [defined in Fail-Safe mA Value (2.4.3.):
VALUE
default 3.58 mA]
VALUE (if ordered with NAMUR NE43 compliant fail-safe preset)
HOLD (if ordered without NAMUR NE43 compliant fail-safe preset)
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