Sensor Mode; Current Output Function - Siemens 7ML5431 Operating Instructions Manual

Appendix A: Technical reference
A.3 Analog Output
A.3.1

Sensor Mode

This parameter controls the input. Depending on the reference point used, the measurement
reports either Level, Space, or Distance. By default Sensor Mode is set to Level.
Operation
NO SERVICE
See Fail-safe Mode (Page 243).
1)
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
②
③
④
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
programmer.
242
Description
Measurement and associated loop current
not being updated. Device defaults to Fail-
safe mode
LEVEL Distance to material surface
SPACE Distance to material surface
DISTANCE Distance to material surface
Sensor reference point
High calibration point
20 mA 100%
Space
.
1)
⑤
⑥
⑦
⑧
Operating Instructions, 10/2019, A5E32220602-AG
Reference point
Low Calibration Point (process
empty level)
High Calibration Point (process
full level)
Sensor reference point
4 mA 0%
Distance
Level
Low calibration point
on the handheld
SITRANS LR250 with mA/HART