Tips on Using PD Clash - PDS - Help

Plant Design System (PDS) Interference Checker/Manager (PD_Clash)




Sometimes, when a clash is detected, the offending item is moved, and interference detection is rerun, the area index numbers get reset to 0 in the project database.


There are only three things that can set an interference marker to 0:

  • One of the models involved in the clash has been re-associated with a different area, or

  • The volume coordinates for the predefined volume get redefined so that the clash (from the first run) that used to reside within the original volume now lies outside the newly defined volume.

    In both of these cases, the clash will be picked up on the next run, on the area within which the clash lies. It will have the same marker number, and all clash history will be intact.

  • The other way marker numbers can be set to 0 is if an envelope file that existed on a previous run does not exist on subsequent runs or if the file is corrupted. For example, an .env file is manually deleted and does not get clash checked on a rerun. If the clash has been previously reported, its area_index_no will be set to 0 until the next run where the .env file is left to be checked and updated.

Envelope Verification Dates

Envelope verification shows you at what times the model (on your workstation) and envelope (on the server) files were created. To ensure that the dates are correct, be sure the time clocks are set to the same time in both places.

Approval Manager > Enter Dynamics Mode

With Reference Models Toggle

When you are checking clashes in the dynamic mode, be sure and toggle With Reference Models/Without Reference Models to with. With Reference Models must be turned on in order to get the true dynamic clash display. Otherwise, the display looks as though nothing is happening.

With the Select View Option

When dynamically reviewing clashes, be sure that Review Clash is checked in order to see the true dynamic clash display. If Window to Clash is used instead, the display window is collapsed around the clash, altering the view depth. You will not be able to see all of the clash because it exceeds the window's view depth.

Structural Database Records

ModelDraft and FrameWorks Plus

There are two records in the database: one for the actual model and one for the propagated model. The Model Status Type for the .dgn file should be set at 1. For the propagated model in ModelDraft, and for the frozen views in FrameWorks, the Model Status Type should be set at 2.

Placing Spheres


Spheres placed with the Microstation Place Sphere command will generate invalid envelopes. The generated envelopes are flat disks instead of spheres. The affected envelope builders include the generic envelope builder used for non-PDS models and any other PDS envelope builder which creates envelopes for spheres placed with the Microstation Place Sphere command.


A surface of revolution with a 180 degree arc creates a spherical envelope.