Survey Interface

To access the General Lift Technocrane configuration panel, click Configure next to the GL Technocrane Pos/Rot Tracker.

Zero the Encoders

After confirming that the crane is in the default position, zero out all of the encoders before continuing the calibration process. This is because some of the steps to derive the pulses depend on the crane starting in the default position.

Entering Points

Click Edit to make the survey point location editable. As each point is measured, enter it into the appropriate survey area. The coordinates for the northing, easting, and elevation points are all in meters, so they can be entered directly from the total station coordinates.

Deselect the Edit button when complete.

Automated Boom Sag

When the initial point and the end point of the boom are surveyed, Previzion will automatically calculate the deflection in the intermediate stages of boom extension. This calculation is based on beam bending, and matches tested data closely without the need to build a lookup table.


Set the Boom Extension Rate

Finally, the various encoder counts/degree must be set. When using the Kuper computer, the various counts per degree are usually set by the operator, so that the Kuper data output is in angles. In this case, the encoder counts/degree are +/- 1.

For installations using the Encodacam serial box, calculate and enter the counts/degree values.

  • 320 tooth swing gear, 56 tooth encoder gear: (18,000 counts/rev)(4x interpolation)(320/56)(1/360) = 1142.86 counts/deg (boom swing)
  • 512 tooth elevation gear, 36 tooth encoder gear = (18,000 counts/rev)(4x interpolation)(512/36)(1/360) = 2844.44 counts/deg (boom elevation)

Setting Boom Extension

Previzion provides for automated setting of the Boom Extension counts/degree. If the encoders were properly zeroed in the default crane position, and the extended Mitchell pivot survey data has been entered in the survey coordinates, do the following:

  • Make sure that the boom is fully extended.
  • Click Set next to ‘Boom is Fully Extended’ to automatically derive the correct counts/degree from the survey.