Siemens Sitrans LR400 Instruction Manual page 54

The URV is always at 20 mA. If you set the current limit to a higher value, you can have the
measured values output outside the measuring range (up to approx. 115%).
4.3.5 Error Signal (F = 3.6 mA)
Current value of the error signal
Value
In the event of a fault the device applies the current defined here to the analog output.
When the Hold... values are selected, the device outputs the last valid value until the
appropriate time has run out or the fault has been eliminated. If the fault persists after the
set time runs out, the analog output switches to an error signal of 3.6 mA.
A fault is different from a loss of echo which indicates a failsafe condition. A
Note:
fault indicates an error with internal electronics, hardware, or software.
4.4 Digital Output
4.4.1 Function DO (F = Alarm)
Assignment of the digital output
Value
Here you can select whether the digital output supplies the upper or lower limit value of
level or an alarm (device error, measurement error; see Parameter 3. 1 ) to the control
system. If you select the
Selection of a limit value enables Parameter 4.4.4. If you select Alarm or No
Note:
function in this parameter, Parameter 4.4.4 will not be visible.
Page 50 SITRANS LR400 (7ML5421) – INSTRUCTION MANUAL
3.6 mA
22.5 mA
Hold 10 s
Hold 1 min
Hold 2 min
Hold 3 min
Hold continuously
MaxLim level
MinLim level
Alarm
No function
option, the digital output is switched off.
No function
7ML19985FH06