Applies To
	Product(s):	Bentley Building Mechanical Systems
	Version(s):	V8i (SELECTseries 1)
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A
	Original Author:	Bentley Technical Support Group

How is the radius on a rectangular elbow calculated?

The radius of a rectangular elbow is controlled via the R1 property, or Inner Radius, which can be set to whatever value is required during placement. If you want to permanently change the default radius, open the Catalog Editor and browse to the  existing "RectangularElbow" component type. Select the DefaultRect item and pick the property R1 in the right window pane. Change the default value to whatever is appropriate, click the Save icon at the top of the dialog box, and exit. The next time a rectangular duct is placed it should use this new default value.

You can also create a new elbow item that would use the desired radius, while maintaining the delivered version. To do so, browse to the existing "DefaultRect" type desired within the Catalog Editor, copy and paste (which automatically creates a  "copy of"), and change the default value for "R1" as desired. The name of this new duct type will also display in the Place Component dialog itself (after exiting and restarting HVAC).  For example, if you named the copy "DefaultRect2", when reopening the Place Component tool (with the Duct/Fitting Type menu set to Elbow) you would see both "DefaultRect" and "DefaultRect2" listed in the Duct/Fitting Name menu directly below. This makes it relatively easy to create and select (right from the interface) a number of duct types based on your specifications.

Can the method be changed which determines the direction of duct take-offs during placement?  

Yes. Key in the Accudraw Shortcut "RR" (Rotate Fitting) in order to change its direction or "?"  to display the entire list of Accudraw Shortcuts.

How are BBMS components resymolized in drawings?  

BBMS components can be resymbolized in a few different ways:

1. Through the part definition's Cut Pattern cell assignment.  The cell assigned here will be superimposed over the "open" end of the applicable BBMS component's 3D graphics in the drawing.

2. From within the component tool's VBA code.  In these cases geometry may be defined within VBA that determines how the component will display in a drawing, outside of the air flow cells assigned by the part definition.

3. As a direct assignment on the element itself using the Building Element Information tool. When selecting a BBMS component using the Building Element Information tool, switching to the Drawing Symbols tab will display the 2D symbol orientations that were applied to that component during placement.  For example, rectangular ducts typically have "Left" and "Right" symbols added so that their ends will display the appropriate air flow symbol:

Elbows, on the other hand, may include additional orientations so that they will display a symbol from multiple directions:

As you select any of the included orientations, you should see a graphic display of that symbol in your 3D model.

Although most components are placed with symbols already defined, you can add orientations through the Drawing Symbols tab if the circumstances require it. See TechNote xxxx for more detail on this process. 

In addition the above, the use of Drawing Rules can also factor in to how BBMS components display in a drawing.  For example, if a Drawing Rule is edited so that the Double Line > Graphics Type option is set to "Symbol", and the symbology changed from the default, the 2D symbols added to the drawing for those components affected will now take on that Drawing Rule's symbology.   

Note that in all cases the "Compound Cell Plan Symbols" toggle located in the Edit Drawing Definition dialog > Cut Plane/Forward View/Reflected View tab (DEM), or the "Drawing Symbols" toggle located in the View Attributes dialog > Building panel> General tab > Forward/Cut/Back (DV) must be checked ON in order for 2D symobols to display.

I see that many part definitions have a specific cell selected under the Cut Pattern part view to be used as BBMS 2D symbols, but I don't understand why those specific cells are selected since there many other similar cells available in HVACDuctSymbols.cel but not used by any part.

The cut pattern cell assigned in the part definition is the one used for Rectangular Duct moving in an upward direction.  For example, DS057 is the cell provided for Supply Duct going up, and is the cell name you will find in the Supply part definition. The other cells related to Rectangular duct begin with the same core name, but add specific suffixes to denote the direction and shape:

D - going down

FO - Flat Oval

R - Round

There are typically six cells defined to cover the three duct shapes and two directions.  Using DS057 as an example, we have:

DS057              Rectangular duct section going up

DS057D            Rectangular duct section going down

DS057FO         Flat oval duct section going up

DS057DFO       Flat oval duct section going down

DS057R            Round duct section going up

DS057DR         Round duct section going down

 

Is there any way to prevent the unit indicator from displaying with my drawing extraction labels? For example, when labeling a round duct I get 18", but I would prefer to see just 18, without the inch mark.

There is no way to remove the unit indicator within a drawing rule or when using the Add/Move Label tool.  However, you can accomplish this by choosing Settings > Design File > Working Units and clearing the sub-unit label, after which you will need to recalculate your drawing extraction. 

How do I set the text & dimension style when using the Add/Move Label tool?

The Add/Move Label tool simply uses the active Text and Dimension style.

When exporting to IFC from BBMS, it seems I cannot map my dataset to the IFC dataset. After clicking on the "Ifc Mapping Information" button from the main "TriForma IFC Export" dialog, the "Ifc Entities" area of the "Map Custom TriForma dataset to IFC dataset" dialog box is blank. Also, in the Message Center I receive the error message "Ifc Mapping settings file not found".  Is it possible to export an IFC from BBMS?

First, make sure that the configuration variable TFDIR_IFC is pointing to your dataset's \setting folder. This is where the IFC mapping file should be stored. But perhaps more important, if you are using BBMS with a straight TriForma dataset and not one from Bentley Architecture, you may be missing the files required for proper IFC export. 

There are three panes in the "Map Custom TriForma dataset to IFC dataset" dialog box, each of which is associated with specific files from the active dataset:

 1) The "Family-Part List" pane on the left displays the parts included in the current project & dataset; i.e., those that would be used during placement, and should automatically populate based on the contents of the applicable \parts folders.

2) The "Mapped Entities" pane at the bottom shows the mapping between those parts and the IFC Entities, which are by default stored in the file "ifcmapping.set" under the \WorkSpace\TriForma\ArchDataset<datasetname>\setting folder.

3) The "IFC Entities" pane on the right displays the available IFC entity types, which are stored in the file "ifc_<datasetname>_parts.xml", by default located under the \WorkSpace\TriForma\ArchDataset<datasetname>\part folder.

NOTE: "<datasetname>" above should reflect your current selection; e.g., NcsUS, UniclassGB, CisfbGB, etc.  

Since IFC has traditionally been very Architecture-centric, BBMS itself does not deliver a set of IFC related files. Therefore, you will need to copy them from the appropriate Bentley Architecture dataset into your WorkSpace\TriForma\hvac_<datasetname>\setting and WorkSpace\TriForma\hvac_<datasetname>\part folders (or their equivalents). This should populate all of the "Map Custom TriForma dataset to IFC dataset" dialog box panes, allowing you to map your BBMS parts to their applicable IFC equivalents.

Note that some customization to the file "ifc_<datasetname>_parts.xml" may be necessary since you are working with BBMS components. In its delivered state this file includes only generic entries such as "IfcDistributionFlowElement" and "IfcFlowFitting".

Is there any way to make components such as Air Handling Units (AHU) specific to certain projects or specfic country codes if needed?

Yes, by using the variable HVAC_STANDARDSMAIN = $(HVAC_SYSTEMSTANDARDS);$(HVAC_COUNTRYSTANDARDS);$(HVAC_COMPANYSTANDARDS);$(HVAC_PROJECTSTANDARDS).

In each of the folders defined by HVAC_STANDARDSMAIN you can add anything that is delivered under $(HVAC_SYSTEMSTANDARDS)\Cells using the same folder structure; e.g., the sub-folders under ..\WorkSpace\hvac\cells which include \AHU, \Fixtures, \PlumbingEquipments and \Symbols. 

For example, you could include country specific data in your HVAC dataset's \Country sub-folder (HVAC_COUNTRYSTANDARDS), company standard data under \workspace\standards and project specific data in your project as defined by $(_USTN_PROJECTDATA).  The priority for loading this data would be to use the project data first (if exits), then the company standard data (if exits), then the country specific data (if exits), at lastly the system level data (if exits). The only condition is that the data must exist in at least one of these locations.

You can perform a simple test for this type of configuration by copying the delivered HVACAHU.cel library from $(HVAC_SYSTEMSTANDARDS)\Cells) [..\WorkSpace\hvac\cells\AHU] to a folder under ..\workspace\projects\examples\[MyProject]\cells\AHU\ and modifying the variable HVAC_PROJECTSTANDARDS=$(_USTN_PROJECTDATA)\cells\AHU\.

As another example, companies that work in multiple countries might put the AHUs themselves in the project data folder and the section symbols in the dataset (based on country standards); e.g., $(HVAC_PROJECTSTANDARDS)\cells\ahu\HVACAHU.cel and $(HVAC_COUNTRYSTANDARDS)\cells\symbols\HVACDuctSymbols.cel, respectively.   The end result can be just about anything that makes sense in the context of your requirements.

I have two ducts that I just cannot seem to connect properly using the Join tool due to a compound angle between them.  I've tried placing both a Transition and an Ogee, but either the component doesn't place at all or the sizes and.or angles are wrong. 

The first thing to try is relaxing the Join tool's tolerance.  If this tolerance is too low you can get odd results (at best) or possibly no component at all depending upon conditions.

Alternately, you could place a Transition by matching the properties of the first duct without actually connecting to the second duct. After placement, use the Edit Component tool to modify the W2 (Width), D2 (Depth), L (Length) and SymAsym (symmetrical\asymmetrical) properties to suit the connection needed for the second duct. You may need to measure and/or place a few construction elements to get the required values, but the process should work once the applicable values are inputted.