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<< Click to Display Table of Contents >> Takeup Response Curve |
  
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<< Click to Display Table of Contents >> Takeup Response Curve |
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The takeup could have a response curve if a mechanical design is used, and may have one if a gravity design is used. The takeup response curve is used to adjust forces resulting from the takeup mechanism, such as drag for sheaves or a limit to the line speed of a winch.
There is no response curve when the takeup pulley is fixed.
Auto or User mode is selected.
•When the auto mode is selected, the software selects the response curve based on the takeup type and known data about mechanical design.
•In the user mode, the user inputs the data points for the response curve.
Curve for “Gravity” takeup type includes effect of sheave drag. When moving out, belt takeup tension is increased; when moving in, belt takeup tension is decreased.
Curve for "Winch Always On" and “Mechanical” takeup type includes effect of sheave drag, maximum line speed and maximum tension.
Curve for "Winch Off/On" and "Hydraulic Cylinder" takeup type includes effect of sheave drag, maximum line speed, Deadband high and low tension settings and maximum tension.
The specific response curve data points can be input into the displayed table; the table has 13 steps of line velocity versus tension response factor. The response factor is the amount of tension added to/subtracted from the normal takeup tension (for example: a response factor of 150 means that the takeup tension will be 150% of nominal running value at this line speed).
Right clicking on the sketch or spreadsheet will pop-up a menu of standard curves.
•No speed response indicates the takeup force is constant. This is typical for a gravity takeup when the weight is directly applied to the takeup pulley.
•A standard line speed response applies to a mechanical takeup device, such as a winch, which has a limited reaction speed so that the resultant takeup force can be a function of the carriage speed.
•If the takeup force is applied through a cable traveling over a series of sheaves, the friction in these sheaves will affect the applied takeup force.
•A mechanical takeup may have both a limit to the speed it can respond and the friction inherent in a series of sheaves.
With a custom takeup type response curves can be automatically created or saved data can be recalled.
•Use “Create” button to automatically input typical curve data from the drop down list.
•Use “Open” button to input saved response curve.
•Use "Save As" button to save the displayed response curve. This is not required for normal running since the curve data is saved with the current DA data files.