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204 Processing
Transportation and material handling
How the length is calculated
When Travel time: speed and calculated length is selected in a Convey Item block, the rel- ative positions of blocks in the model, and their connections, determine the path’s length. The following example explains how the length is determined.
The bottom potion of the Behavior tab for a Convey Item block is seen at right. In this frame:
• The 2D From x location is 211 pixels (the position of the previous non-pass- ing block) and the To x location is 344 pixels (the position of the next non- passing block).
Length calculations for Convey Item block
• Bydefault,thelengthiscalculatedinastraightlinebetweenthefromlocationandtheto location. (The alternative is to calculate the distance along the connections.) The shape of the block’s object will not visually change with either choice, but the choice affects the determi- nation of the path’s distance. For instance, if there were a series of right-angle connections between the from and the to locations, and along connections was selected, the distance would be longer than if the straight line option had been selected.
• The Distance ratio (pixels per meter) is based on the 3D distance ratio set in the command Run > Simula- tion Setup > 3D Animation tab. The default is 20 pix- els per meter, as shown at right.
In addition, the block’s Block Animation tab is set by default to stretch the object to the conveyor’s length. This will cause the Conveyor object in the E3D window to auto- matically resize to reflect the calculated length.
Distance conversion ratio
Setting in Block Animation tab
How the settings affect the length
The distance between the previous non-passing block (the from location) and the next non- passing block (the to location) is calculated in a straight line between the output connector of the from block and the input connector of the to block. This is 133 pixels (344 pixels - 211 pix- els).
The distance ratio of 20 pixels per meter is used to convert the 133 pixels into meters. The result is the length of the conveyor: 6.65 meters. as can be seen in the block’s Behavior tab. (This is also reflected in the 3D information, where the From x location is 10.55 meters and the To x location is 17.2 meters, a difference of 6.65 meters.)
☞ If the from and/or to locations are blocks, the determination of the length starts at one block’s output connector and ends at the other block’s input connector.
Moving this Convey Item block along the connection line between the from and the to blocks will not have any affect on the conveyor length. This is because the distance between the from and to locations stays the same. However, moving the from block away from the Convey Item
Discrete Event

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