4.4.12 Setting the damping applied to the output

Screen display

d

 

Factory default value

3

The damping value entered is actually a time constant in seconds which is applied as smoothing to the displayed PV and current output.

A new value may be entered up to a maximum value of 9999 seconds. A large value will have the effect of smoothing out rapid changes of current output and will also smooth out the effects of turbulence and ripples on the liquid surface.

Note, it would not normally be necessary to select a value greater than 30 seconds.

Alternatively, a value of zero may be entered in which case no smoothing is applied and changes in reading immediately change the current output.

Note, as the MSP400 transmits a pulse at nominally once per second, a damping time of zero will not necessarily give an immediate change in output.

To edit the damping value:

a)Press the blue button to enter the damping menu and to display the current value in use. If this is correct, press the green button return to the main menu.

If the damping value is to be edited, press the blue button again to allow editing

The leading digit of the current damping value will now be flashing, indicating it may be changed.

b)Use the green button to edit the value of the leading digit.

c)Once correct, use the blue button to select the next digit and then the green button to edit as before, or the blue button to move to the next digit. Continue this sequence until all the digits are correct.

d)Press the blue button a final time to confirm the new value. None of the digits should now be flashing.

If the new damping value is incorrect, the edit sequence for the 20mA point can be re-started by pressing the blue button again.

If the damping value is correct, press the red button to save the new value to memory and automatically scroll on to the next main menu option: “AL”

4.4.13 Selecting the output current action on alarm condition

Screen display

AL

Factory default value

Hold

The MSP400 will signal an alarm condition in the event that the target echo is lost for a period of 900 seconds or more. This time of 900 seconds is factory set and is changeable in the field.

(See Section 4.7.2)

The user can select what action the current output will take in the event of a lost echo condition:

Hi

The current on the two wire loop will drive up to 21mA and will remain there until a correct target

 

echo is recovered. The display will flash “LE” and the alarm action alternately.

Hold

The current will freeze at the value it was last reading and will remain there until a correct target

 

echo is recovered. The display will flash “LE” and the last valid reading alternately.

Lo

The current on the two wire loop will drive down to 3.6mA and will remain there until a correct

 

target echo is recovered. The display will flash “LE” and the alarm action alternately.

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IP2046/IM

Nov 2006

 

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Emerson MSP400RH, IP2046IM manual IP2046/IM