Page 378 - ExtendSim User Guide
P. 378

Creating Flow
from the end of the conveyor. For more information, see “Distribution of flow” on page 416.
Setting indicators
The Indicators tabs on all
three residence blocks
have similar interfaces.
Each Indicators tab has a
table (shown on the right
with example settings) for
specifying an indicator
name for each range of
values, entering the low
limits, and defining values (an ID number for each indicator) to output when the block's flow level falls within a particular range.
To create indicators, enter your own information or click the Show Example button to populate the table with some example indicator names and settings. In either case, ExtendSim will cal- culate the High Limit values based on the Low Limit entries.
☞ The top row has to have the highest range; the bottom row must have the lowest range.
☞ To add or delete table rows, use the +/- button in the table's lower right corner. For instance, to
delete the example settings, change the number of rows to 0.
The screen shot above shows a Tank’s names, limits, and ID values to output after the Show Example button has been clicked. Each indicator name corresponds to a range of flow contents defined by the Low and High Limits for that row. (The High Limit column is presented for clarity only, since those numbers are calculated using the values entered for the Low Limits.)
Unless the block has infinite capacity, the indicator limits can be expressed in absolute num- bers (shown above) or as percentages.
See “Bucket Elevator 2 model” on page 429 for an example of how indicators are used in an Interchange block to control a Valve’s effective rate.
☞ If the block has infinite capacity, the limits must be expressed as absolute numbers. If the block's initial contents are set to infinity, the indicators are disabled.
Getting information about levels
There are two types of events that will cause a new indicator to be reported:
• When the level is
increasing and the
block’s contents reach
the next indicator’s Low Limit.
• When the level is decreasing and the block’s contents reach the next indicator’s High Limit.
In each case, the new output ID is used to update the I value output connector, and any con- nected blocks are alerted to the change.
Using the above table as an example, if the level in the Tank increases from 120,000 to 175,000 containers, the block will compare that level to the Low Limit and send the value 3 to
Example indicators in Tank block
Example indicators in a Tank
Discrete Rate

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