There is also a wiki on this.
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Forum Post: RE: How to select junctions connected to any particular ( 100mm ) diameter pipes?
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Wiki Page: Select end nodes of pipes in a selection set
Applies To Product(s): Bentley WaterCAD, WaterGEMS Version(s): 08.11.XX.XX Environment: N\A Area: General Subarea: N\A Original Author: Dan Iannicelli, Bentley Technical Support Group Problem How do I select the end nodes of pipes in the selection set ,say end nodes of pipes of certain diameters only, not all the pipes? Problem ID#: 59982, Solution This can be done using a tool called Network Navigator. Highlight pipes in the selection set. Go to View > Network Navigator. Choose the ">"button and go to Network Trace > Find Adjacent Nodes. The nodes attached to the highlighted pipes will appear in the Network Navigator dialog. You can highlight the nodes in the drawing by selecting the"Select in Drawing" icon. You can then apply them to an existing selection set or a new one. This is done by right-clicking in the drawing pane with the elements highlight and selecting with "Add to Select Set" or "Create Selection Set". (Please visit the site to view this video) See Also
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Forum Post: RE: How to select junctions connected to any particular ( 100mm ) diameter pipes?
Thanks a lot Sushma.
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Forum Post: check valve closure
Dear all, How should I model a swing type air valve in Bentley HAMMER. I also want to know how the closure time (Operating time) of check valve is incorporated in the analysis, specially how to determine the actual closure time of a check valve. I really appreciate your response. regards, Nalaka
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Forum Post: RE: check valve closure
Hello Nalaka, You had submitted your question to the Communities Feedback forum. I have moved it to the Haestad | Hydraulics and Hydrology Forum There are several ways to model a check valve in HAMMER, as described in this article: Modeling Reference - Check Valves If you're not comfortable assuming an instant closure (such as with a check valve enabled in the properties of a pipe), then the check valve node element is recommended. It gives you more control over the open and closure behavior. It sounds like you are using the check valve node element, but unsure of the parameters. You can see some definitions in the above article, but basically the Open Time and Closure Time in the check valve node properties is entered by the user based on specifications from the manufacturer, or from the engineer's best judgment. I would recommend getting some information from the swing check valve manufacturer. In general, a longer closure time can sometime cause a more severe transient if significant reverse velocity occurs before the closure, but it may be possible for the opposite to occur. So, it may be best to try out a value that you feel is appropriate and check the transient response. In some cases a sensitivity analysis may be appropriate - try a range of values for the parameter that you're unsure of (such as closure time) and check how the results change. This will give you a feel for how sensitive the particular model is to the parameter. You may need to set up a profile that focuses in on just a few pipes around the check valve, and use a small calculation timestep with Report Times set to "all" and "generate animation data" set to "true". This way you'll be able to see enough detail to understand the check valve's response.
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Wiki Page: Why does the gutter need to be defined in both the catch basin and gutter element?
Product(s): Bentley StormCAD, Bentley CivilStorm, Bentley SewerGEMS Version(s): 10.00.xx.xx, 08.11.xx.xx Environment: N\A Area: Modeling Subarea: N\A Problem The gutter and catch basin elements both seem to have the same fields for defining whether the gutter was depressed and then what the gutter cross slope and gutter width are. Why is that? Problem ID#: 88880 Solution In the gutter element these fields define the gutter shape up to (upstream of) the inlet itself. In the inlet these fields define the gutter shape just on the upstream side of the inlet opening where the spread is highest. The gutter shape can be different at these locations, for example if there is a local depression at the inlet location. In cases where the gutter shape is the same as the gutter at the inlet location, choose "Same as Start Node Gutter" for the field "Gutter Type" in the properties of the gutter. Original Author: Mark Pachlhofer
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Wiki Page: When changing the road cross slope in a model, the gutter spread and depth values are not changing in the results.
Product(s): Bentley StormCAD, Bentley CivilStorm, Bentley SewerGEMS Version(s): 10.xx.xx.xx, 08.11.xx.xx Environment: N\A Area: Output and Reporting Problem When changing the road cross slope in a model, the gutter spread and depth values are not changing in the results. Solution If you are using a catalog gutter, you will need to change the road cross slope and other gutter properties in the catalog gutter dialog. This is because the properties for catalog elements takes precedent over properties in the properties grid. A future release of the product will make this more clear. In the meantime, you can change the road cross slope by opening the catch basin properties grid, selecting the pulldown menu for "Catalog Gutter" and choosing Edit. You can also access the gutter catalog by going to Components > Catalog > Gutter Catalog (in the CONNECT Edition of the software) or Components > Gutter Catalog (in the V8i release). Select the appropriate gutter and change the road cross slope. Once this is open, adjust the road cross slope value. When you recompute the model, the results will change. If you are comparing different road cross slope values, you may want to create a new catalog gutter to use instead of editing the existing one. That way the original gutter properties will still be available if you want to return to those. See Also Why does the gutter need to be define in both the catch basin and gutter element?
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Wiki Page: Is it possible to model a conduit that is larger on the downstream side compared to the upstream side?
Product(s): Bentley StormCAD, Bentley SewerCAD, Bentley CivilStorm, Bentley SewerGEMS Version(s): 10.00.xx.xx, 08.11.xx.xx Environment: N\A Area: Modeling Problem Is it possible to model a conduit that is larger on the downstream side compared to the upstream side? In other words, can a conduit change size as it moves downstream? Solution Conduits are assumed to be the same size along its entire length. If you want to model a conduit where the size is changing, you would need to model the conduit as several conduits with varying size. For instance, consider a case where a conduit that is 60 feet in length and is 12 inches in diameter on the upstream end and 24 inches in diameter on the downstream end. In order to model this change, you will need to model this as more than conduit separated by a transition or manhole element. You could model this as three conduits, each 20 feet in length. The first conduit would be 12 inches in diameter, the second conduit would be 18 inches in diameter, and the third conduit would be 24 inches. Between these would be a transition element at the appropriate invert elevations to account for the slope. If needed, you could use the Element Property Inferencing tool to help define the elevations. If you wanted a finer level of detail, you could use more conduits as well.
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Wiki Page: Importing A CAD (DXF) Drawing Using ModelBuilder [TN]
Applies To Product(s): WaterCAD, WaterGEMS, HAMMER, StormCAD, SewerCAD, SewerGEMS, CivilStorm Version(s): 08.11.XX.XX Environment: N/A Area: Layout and Data Input Original Author: Jesse Dringoli, Bentley Technical Support Group Overview Some older versions of the Hydraulics and Hydrology product line (WaterCAD, WaterGEMS, StormCAD and SewerCAD) used a much different procedure for converting "polylines to pipes", compared to the 08.XX.XX.XX versions. This TechNote provides tips and techniques for effectively importing a CAD drawing into V8 XM or V8i using the new method. This procedure is similar for WaterCAD, WaterGEMS, HAMMER, StormCAD, SewerCAD, SewerGEMS, and CivilStorm. Background In older versions of WaterCAD, WaterGEMS, StormCAD and SewerCAD, the user would import a CAD drawing (.dxf or .dwg) via File > Import > Polyline to Pipe . Upon release of the V8 XM edition, this functionality was merged into Modelbuilder, which is a powerful tool used to import many different types of data. Since the steps in the Modelbuilder process are very similar for most data source types, there are some extra options involved for a CAD drawing, which could initially cause some confusion to new users of V8 XM and V8i. Preparing the CAD Drawing 1. First, you should take some time to clean up your CAD drawing prior to performing the conversion. Look for entities that should not be converted, such as leader lines, and move them to their own layer. Turn off or remove layers that you do not wish to convert. Do a quick review of your drawing and correct any potential conversion problems that you may find. Note: It is recommended that you perform a "save-as" before cleaning up the drawing, so that you can retain the original. 2. Next you will need to save your CAD drawing into a DXF format, as this is the only CAD type format that Modelbuilder currently accepts. DXF is the "drawing exchange format", so almost all CAD programs have the ability to save to it. Whenever possible, try to save to the earliest DXF format, for better compatibility. For example, in AutoCAD, go to File > Save As, and choose "2004 DXF" as the format. Importing Your CAD Drawing Using Modelbuilder Note: This process remains the same whether you are in the standalone, AutoCAD, Microstation, or ArcGIS platform. This process also assumes that you have certain pipe diameters separated by layer and that you're using V8i version of the software. If you're using V8 XM instead, the steps in the Modelbuilder process will look slightly different, but basic procedure remains the same. 1. Open WaterCAD/GEMS and start a new project. Ensure that the correct unit system is specified.Go to Tools > User Data Extensions. 2. Right click on "Pipe" and choose to create a new user data extension. We will import the layer name into this field so that we can assign diameters at a later point. Give it a name, keep the default data type of "Text" and click OK. 3. Start Modelbuilder by going to Tools > Modelbuilder. In the main window, click the "New" button to start a new Modelbuilder run. 4. In the first step, select "CAD Files" as the Data Source type and browse to your .dxf file. Once selected, a table will be displayed in the lower left corner, showing all the layers that exist in the drawing. Layers that you would like to be imported should be checked. Unchecked layers will not be imported. The layer type will be displayed after the name of each layer, showing you if the layer contains points, lines, or polygons. In this example, we have checked only the layers that represent water distribution pipes of various diameters. Layers containing roads, annotations,and other irrelevant items have been unchecked: Note: If you have a lot of layers that need to be unchecked, you can right-click anywhere in the list and choose "clear selection". Note: In many cases, nodal elements such as tanks, pumps, etc are represented in a CAD drawing as a series of lines. In this case, they cannot be imported as their respective nodes in the modelbuilder process. The user must enter these elements later on after the import. 5. Click the 'Next' button to proceed to the second step. In this step, you should select the appropriate unit and also make sure the check box next to "Establish connectivity using spatial data" is checked. This option allows Modelbuilder to use the spatial information inside the CAD file (lengths, coordinates of endpoints/bends, etc) to build the model, instead of the user needing to explicitly specify the start/stop node (which is typically not possible for a CAD drawing.) In addition to this, the "Tolerance" field will allow Modelbuilder to automatically connect pipe end points that are within the specified value. Make sure "Create nodes if none found at pipe endpoint" is checked. In most cases, only polylines are imported from a CAD drawing, so you'll want junctions to be created at the ends of these. For the "Tolerance" options, take the following CAD line for example In this zoomed-in view, notice that a gap exists due to drawing imperfections. This gap is 1.5ft wide. Now, if we import this CAD file with 1 ft. set as the tolerance it will create two nodes at the actual end points of these pipes This is because the distance between the end points was not within the tolerance. If we were to instead import this drawing with a 2ft tolerance, it would connect these end points and join them at a junction: 6. Next, you will only need to keep the "Add objects to destination if present in source" box checked, since we are creating new elements based on the CAD drawing data. 7. In step 4, accept the defaults of "Current scenario" and "Label". 8. In step 5, you must configure how the data in each layer is mapped to WaterCAD/GEMS. Click each layer from the list on the left and then configure the attributes on the right: "Table Type" This is used to select the type of element that a layer will be imported as. For a CAD file, you will most likely be importing polylines only. So, this field will be set to "Pipe" (for WaterCAD, WaterGEMS and HAMMER) or "Conduit" (for SewerCAD, SewerGEMS and CivilStorm). "Key/Label" This is the field used to create labels for the elements created by the modelbuilder process. It is also used to link up elements when updating existing ones. In the case of importing a CAD drawing, most likely a field containing unique labels does not exist for the polylines. So, you should select " " for each layer. This will cause Modelbuilder to automatically generate unique labels, utilizing a combination of an element's layer type label, its shape type, and a numeric ID that represents the order in which it was created. "Start"/"Stop" Choosing the "Establish connectivity using spatial data" causes the connectivity information to be taken from the CAD drawing, so you do not need to specify a start/stop node field for the pipes/lines. So, simply leave these as " ". "Attribute" At the bottom right corner of this Modelbuilder step, the user can link fields in the source data to fields in the program. In the case of a CAD drawing, typically there are no additional, useful attributes. However, you could link the "Layer" field to the user data extension attribute that you created in step 2. In this example, the user data extension was named "AutoCADLayer": By linking this field, there will be an attribute in the WaterCAD/GEMS model that contains the name of the layer that the pipe came from. Later on this will be useful. Note: Make sure that you set the key/label field and "layer" mapping for each layer. If your DXF contains points, they will show up as separate layers on the left side. You can then click and assign them to a node element type such as Junction. 9. In the last Modelbuilder step, choose to build the model. Modelbuilder will then import the layers and provide you with a summary, including a "Messages" tab that you can use to view informational messages about the import process. In this case, there are some messages about nodes being created due to missing start/stop nodes. This is expected since we were only importing polylines, with the "Create nodes if none found at endpoint" option selected. 10. After closing the summary and closing Modelbuilder you will be prompted to synchronize the drawing. Choose "Yes" and your model should show up in the drawing area. If it does not, then go to View > Zoom > Zoom Extents. Note: Upon completion of your ModelBuilder run, it is suggested you use the Network Navigator tool to identify any connectivity or topological problems in your new model. Assigning Pipe Diameters Now that our model has been created, we can assign diameters to the pipes, based on the layer attribute that we imported. 1. Open the pipe flextable via View > Flextables. 2. Click the yellow Edit button ( ) and add your user data extension. To do this, first find it in the list on the left side, click on it, and then click the single arrow button pointing to the right side. Click OK and you will now see a column in the flextable, containing the layer that each pipe came from. In our example case, the layer "12_WATER" represents 12" pipes, "16_WATER" represents 16" pipes, and so forth. 3. Right click on any of the column headers, choose "Filter", and select "Custom". In the query window, double click on your user data extension field from the list on the left and click the equals sign button. Then, click the green button on the top-right corner to retrieve a list of unique values from this field. Double click on one of the diameters (layer names) shown. In our example case, we'll start with the 10" layer: When you click OK in the query window, the flextable will be filtered to only show pipes that came from the layer that you queried on (those from the "10_WATER" layer in our example case.) Note: After performing your filter, the bottom left corner of the flextable will show you how many pipes met the query condition and are displayed (for example "68 of 4714 elements displayed") 4. Now, assign the correct diameter by right clicking on the "Diameter" column header and choosing "Global Edit". Keep the operation as "Set", and enter the appropriate diameter as the value. Click OK and your diameters will be assigned. 5. Repeat steps 3 and 4 for each layer, assigning out all your diameters. Note: When done, you can reset your filter by right clicking on any column header and then choosing Filter > Reset. Note: An alternative way to assign diameters would be to bring each layer in one by one. Instead of using the user data extension, create a Prototype under View > Prototypes, and set the pipe diameter to the smallest one in your CAD Drawing. Next, uncheck all layers in the first Modelbuilder step except for the one corresponding to that diameter. Import the pipes per above and they'll be assigned the diameter specified in the prototype. Next, change the pipe prototype diameter to the next size, open the Modelbuilder run again, uncheck the first diameter and check the next one. Continue on like this for each diameter. Troubleshooting When importing a DXF layer which contains only lines or polylines, ModelBuilder recognizes the layer as a polygon instead of polylines. Make sure all polylines have a length. The DXF layer may contain a point (line without length). Other applications such as MicroStation and AutoCAD may recognize the element as a polyline, but ModelBuilder does not since the endpoints are at the same location. Either delete these points or replace them with a line that has a length. This is also discussed in this article . See Also Building A Model Using ModelBuilder [TN] Updating A Model Using Model Builder Not all the layers in my DXF file are showing up in ModelBuilder Product TechNotes and FAQs Haestad Methods Product Tech Notes And FAQs Hydraulics and Hydrology Forum External Links Bentley SELECTservices Bentley LEARN Server
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Wiki Page: Why is the system time at one of my nodes much larger than the upstream nodes Tc or system time?
Product(s): Bentley StormCAD, Bentley SewerGEMS, Bentley CivilStorm Version(s): 08.11.XX.XX Environment: N\A Area: Calculations Subarea: N\A Problem Why is the system time at one of my nodes (catch basin, transition) much larger than the upstream nodes time of concentrations or system time? or How is flow calculated for the GVF-Rational Solver (StormCAD) Problem ID#: 64653 Solution Most likely the reason why this is happening is the following: The problem is that the time of concentration is added to the pipe travel time a.k.a (Time (Pipe Flow)) under the Results (Hydraulic Summary) for pipes which determines the system time. As stated in the help documentation, when combining rational loads, the controlling time (aka system time) is the greatest of the individual loads' system times. Therefore the system time at a given transition X with one upstream node and a pipe connecting to it would be computed as follows: Catch Basin Y has a time of concentration of 5.00 minutes + the Time (Pipe Flow) for conduit Z which would be 71.193 min = a system travel time of at transition X of 76.193 min. Similar to a time of concentration, a system time (or controlling time) is the amount of time it takes for all contributing parts of the storm sewer to reach a given location. This includes a catchment's time of concentration, and pipe travel times. When combining rational loads, the controlling time is the greatest of the individual loads' system times. This system time is used as the duration of the storm when determining peak intensity, and therefore peak flow. To avoid unreasonably low storm durations and unreasonably high rainfall intensities, many regulatory agencies impose minimum storm durations, typically 5 or 10 minutes. StormCAD allows you to specify a minimum storm duration and uses this as the controlling time when the computed time is too low. In these cases, StormCAD carries the computed system time throughout the system, but continues to calculate intensity based on the minimum allowed time (until the system time rises above the minimum). For example, consider a catchment at I-1 with a time of concentration of 4 minutes, and a minimum allowable duration of 5 minutes: I-1 Catchment time of concentration: 4.0 minutes StormCAD computes flow based on: 5.0 minutes P-1 Pipe travel time: 0.5 minutes J-1 System time (4.0 + 0.5): 4.5 minutes StormCAD computes flow based on: 5.0 minutes P-2 Pipe travel time: 1.0 minutes O-1 System time (4.5 + 1.0): 5.5 minutes StormCAD computes flow based on: 5.5 minutes This 5.5 minutes is used as the duration in the intensity vs. duration equation used to calculate in determining the flow using: Q = i (CA) Original Author: Mark Pachlhofer
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Forum Post: Long-term simulation use real time/date in graph
Hi, I'm using SewerGEMS for a long-term simulation and I would like to change the time axis in the graphs by date and time that I set in the calculation option. Is it possible? thank you!
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Forum Post: SCADA DATA
Hello, I have scada data and would like to enter my WaterCAD model as making some guia .... THANKS...
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Forum Post: RE: Long-term simulation use real time/date in graph
Marie, You can't change the bottom axis to have the date, but you can set it up so that you see 12 or 24 hour periods. Graphs also have the options of being able to change the label from "Time (Hours)", which I believe is the default. You can find information for how to do that in this wiki: communities.bentley.com/.../20230.how-do-i-change-my-the-chart-options-on-my-graphs-so-they-start-at-a-certain-time Regards, Mark
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Forum Post: RE: SCADA DATA
Leonidas, The following wiki describes how you can go about entering your SCADA data. When the option is open for source type make sure to choose Excel 8.0 for an .XLS format file or Excel 12.0 for a .XLSX file type. communities.bentley.com/.../18684.scadaconnect-in-sewergems Regards, Mark
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Forum Post: Pump VSD during transient
Hi, I am modelling a pumping system, with one pump on a ‘fixed head’ VSD controlling the pressure of a header pipe which distributes to six drains via orifice plates. I am trying to model a transient case where one of six isolation valves closes rapidly (using a TCV element). However during a transient run, when the valve closes, the pressure in the header rises, but the VSD does not respond to slow down the pump and maintain the target pressure in the header pipe. Does the Hammer variable speed drive function during a transient? Do you have any suggestions as to how I could model this case (e.g. do I need to use a variable speed pump battery element, or do I need to manually enter a pump transient operation rule to match the closure of the valve)? Also is there a way of setting a delay or deadband on the vsd during a transient? Thank you
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Wiki Page: Why do I get zero available fireflow for one or more nodes in my fireflow report?
Applies To Product(s): Bentley WaterGEMS, Bentley WaterCAD Version(s): 08.11.XX.XX Environment: N/A Area: Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem Why do I get zero available fireflow for one or more nodes in my fireflow report? Solution This is likely due to the pressure or velocity constraints being violated, even with the baseline demands. In the Fire Flow Table, check the fields "Pressure (Calculated Residual)" and "Pressure (Calculated Zone Lower Limit)". In some cases, other constraints may be used as well. The automated fire flow has the option to assign pressure constraints for the whole system, as well as velocity constraints. Go to your Fire Flow alternative to confirm if you are using these. If so, also check the fields "Pressure (Calculated System Lower Limit)" and "Velocity of Maximum Pipe". See Also Understanding Automated Fire Flow Results
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Wiki Page: How is flow balanced at junctions with the GVF Rational Solver (StormCAD)?
Applies To Product(s): Bentley SewerGEMS, Bentley CivilStorm, Bentley StormCAD Version(s): 08.11.XX.XX Environment: N/A Area: Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem How is flow balanced at junctions with the GVF Rational Solver (StormCAD)? Solution Because of the use of rational method hydrology, flow discontinuities may be noticed. This is a condition where the sum of the inflows does not equal the sum of the outflows. The main reason for this is that the rational method is only concerned with peak flows and has a high dependence on duration (system time). As the system time changes, the intensity changes and has a direct effect on the rate of flow in the system. The most common cause of confusion with this discontinuity stems from rational loads that are tracked through a long piping system without any other loads entering the network. At the inlet of origin, the time of concentration may be relatively small, resulting in a high intensity and a large peak discharge. As the load travels through the pipes, the system time becomes larger, so the intensity lowers. This results in smaller discharge values, so the peak flow at the outlet may be significantly smaller than the peak flow at the original inlet. This may seem counter-intuitive at first, with questions like "Where did the rest of the flow go?" coming to mind. In reality, the rest of the flow was not lost, but an attempt to balance peak flows is not valid. Picture standing at the top of a hill with a bucket of water. If you empty the entire bucket into the gutter in one second, then the peak rate of discharge at the top of the hill is one bucket per second. Racing to the bottom of the hill, you can observe the flow and see that the peak flow is much less than one bucket per second. However, the flow lasts longer than one second. There was no water lost, but the peak was lower. StormCAD does not simply add flow at a junction node; rather, it takes into account the attenuation of peak flow as one moves downstream by keeping track of upstream catchment properties and decreasing the peak intensity according to the time of concentration and travel. The flow out of a catchment is: Where : Q = Flow C = Coefficient i = Intensity a = Area And the flow out of a junction is: Q (out) = Sum (C * i * a) + Sum (Q known) One would think therefore that flow in equals flow out. However, the intensity (i) used for determining the flow into the manhole will be higher than the intensity of the flow leaving the manhole. This intensity is calculated using the longest possible flow travel time in order to generate the most conservative value for peak flow. For example, say a catchment empties into a catch basin and has a Time of Concentration of 10 minutes. On the other hand the travel time of the piped flow getting to the catch basin is 12 minutes. The rational flow generated at the catch basin will be generated based on the intensity associated with the 12 minute duration. This way you are assured that the whole system is contributing to the flow and hence you are using the most conservative peak flow value at that point. If you do not wish to have this flow attenuation taken into account, you should specify Known or Additional flows at the catch basins. See Also Why is the system time at one of my nodes much larger than the upstream nodes Tc or system time?
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Forum Post: RE: Long-term simulation use real time/date in graph
Hello Marie-Joelle, Are you looking to change the bottom axis to show dates instead of time from start? If you right click on the bottom axis and choose "Time Properties", (this was introduced in V8i SELECTseries 2 ) there are a number of different date and time formats available. Here is an example of Short Date: Here is an example of "Short Date & Short Time": The dates should show up appropriately based on the simulation start date. In other words, the first date on the left side of the graph should be the simulation start date.
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Forum Post: RE: Pump VSD during transient
Hello Luke, Hammer assumes that the pumps are controlled by an operating rule or, in the case of the "Shut down after time delay" transient pump type, a time value at which the pumps will stop operating. You will need to setup the operating rule to model this transient event of valve closure. The below article contains information about variable speed of pump in Hammer, which you may find useful.
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Forum Post: RE: Long-term simulation use real time/date in graph
Thank you this is exactly what I wanted to do!
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