After making a change to the length between 2 node points ( on the Points tab of the input grids, noticed in the model it looked as some node points were now disconnected.
Also found the following was displayed in the Model Consistency Check report:
W726-34: Inconsistent coordinates were reset at following point(s)
What Causes it and how to avoid it?
First step is to understand what happens when a node point location change / update is made and how that affects the rest of the node points down stream of that modification.
A node point location can be modified by using any of the following methods:
1. Modify> Run command
2. Update the Node point location directly on the Point Tab of the Input grid
3. Edit> Move / Stretch command
The user should understand the benefits and drawback of each procedure before using any one particular method.
Note: AutoPIPE models are built by first establishing an Origin point and then inserting a delta distance to the next node point. This process is continued until the end of the existing segment or a new segment is started. Again the new segment will have an Origin point and progressing to the next node point based on the delta distanced entered. The continues until the model is finished. A model may contain a Single segment or multiple segments on multiple disconnected systems. It all depends on the modeling required by the project being analyzed.
This command requires the user to first be on the node point that is to be modified before using this command. After the command has been started, the following dialog opens:
Allowing the user to update the coordinates, yellow colored area, of that point as needed (ex, changed Length from 3.00 ft to 5.00 ft). Another words the Delta Offset from the exiting node point (B01) to the next node point (B02) and the following node point (B03) are being changed. This modification will only affect a single node point (ex. B02) and the Delta offset distances from the node point before and after.
Imagine B01 is the starting point and B03 is the end point. Node point B02 lies somewhere between them both (ex. B01-B02 = 3.00 ft and B02-B03 = 3 ft, therefore there is 6 ft between B01- B03). Any modifications on the Run Point dialog, yellow shaded area in the image above, will relocate node point B02 from B01 as defined by the new values. However, regardless of where B02 is relocated, B03 has not moved and the delta offset is automatically calculated between B02 - B03.
In this example, B02 moves along the X-axis between B01 and B03, B02 delta offset is manually changed from 3.00 ft to 5.00 ft. Therefore, since the distance between B01 - B03 is 6.00 ft, and B02 is now 5.00 ft from B01, the distance from B02-B03 is automatically calculated as 1.00 ft
There is one very important feature on this Modify> Run dialog, "Apply offsets to all following points"
See AutoPIPE help for complete details on this feature.
"Enable this option to move all points following the current point by the offsets specified in this dialog. "
With this option enabled, all the node points downstream of this node point will be affected by the delta distance applied by changing the node point location (ex. changing B01-B02 from Dx=3.00 to Dx=5.00 ft, is essentially adding 2.00 ft in the +Dx direction to all the node points from B03 to the end of segment).
Depending on how the model is created and segment orientations there may be some locations in the model that may appears as if the piping is now disconnected (ex. D00).
However upon closer inspection the end point has the same Node point name.
Question: Why does the node points on both sides of the disconnect have the same node number (ex. D00)?
Answer: Because it is not a split pipe, actually the pipe is stilll connected, but the Graphics need to be updated.
To update the graphics, select Tools> Model Consistency Check command, note the error message above will appear in the the report and then close the report. Presto, the graphics have now been updated:
At this point, there are only 2 options to consider:
a. Undo this action and perform another procedure that yields the correct pipe modifications.
b. Accept this modification and continue to modify the piping as needed.
The user can move node points by updating any of the following values on the Input grid> Point tab:
Note, any changes to these 3 types of values on this tab assumes that the "Apply offsets to all following points" option is automatically enabled or is being considered. Therefore the above statements and images apply.
Select a single node point or a range of connected node points,
Select Edit> Stretch/Move command
Stretch the piping as far and in any direction as needed (ex. stretch the selected piping an extra 5.00 ft in the +X-dir, set DX: 5.00 ft)
Notice the highlighted pipe was stretch / moved to a new location and the connected piping automatically adjusted as needed (ex. highlighted pipe B02-B05 was stretch/moved 5 ft, the connected piping runs B01-B02 & B05-B06 automatically adjusted to the new location by updating from 3.00 ft to 8.00 ft. A difference of 5.00 ft).
Each of these 3 methods can be used for modifying the node point locations in an exiting model to compensate for piping changes in the field or by design. They are very powerful features that will perform exactly as directed by the user depending on:
Because of this the warning message above may appear when running a Model Consistency Check report. Each method has its proper time and circumstances to be used, Think about what you are trying to accomplish and use the correct method to attain your goals. Even if it was a mistake, use the Undo feature, try to understand where the mistake was made and try again with a slight variation until the modification is correct.
Question #1, What Will happen if Segment D direction was reversed, where would the offset occur?
Answer: click here
Question #2, What Will happen if Segment E direction was reversed, where would the offset occur?
Warnings Messages displayed in AutoPIPE