Fail-Safe - Siemens LR250 Instruction Manual

2.5. Fail-safe

Note: Default settings in the parameter tables are indicated with an asterisk (*)
unless explicitly stated.
2.5.1. Material Level
Note: The default setting depends whether your device is a standard or
NAMUR NE 43-compliant device.
Defines the mA output to use when the Fail-safe Timer expires.
Options
Options
2.5.2. LOE Timer
Note: When a Loss of Echo occurs Material Level (2.5.1.) determines the
material level to be reported when the Fail-safe timer expires. See
Echo (LOE)
Sets the time to elapse since the last valid reading, before the Fail-safe Fail-
Safe mA Value is reported.
Values
2.5.3. Fail-Safe mA Value
Notes:
• The default setting depends whether your device is a standard or NAMUR
NE 43-compliant device.
• Material Level (2.5.1.) must be set to VALUE to enable the Fail-Safe mA
Value value to be reported.
Allows the user to define the mA value to be reported when the Fail-safe timer
expires.
Device Type
Values
Page 86 SITRANS LR250 (HART) – INSTRUCTION MANUAL
STANDARD DEVICE
HI 20.5 mA (max. mA Limit)
LO 3.8 mA (min. mA Limit)
* HOLD Last valid reading (default 22.6 mA)
VALUE User-selected value [defined in Fail-Safe mA Value (2.5.3.)]
NAMUR NE 43-COMPLIANT DEVICE
HI 20.5 mA (max. mA Limit)
LO 3.8 mA (min. mA Limit)
HOLD Last valid reading
User-selected value [defined in Fail-Safe mA Value (2.5.3.):
* VALUE
default 3.58 mA]
on page 138 for more detail.
Range: 0.00 to 7200 seconds
Default: 100 s
STANDARD
Range 3.56 mA to 22.6 mA
Default 22.60 mA
Loss of
NAMUR NE43-
COMPLIANT
3.58 mA
7ML19985JE06