Exporting to INP error

Question

Hello, 
 Every time I try and export my scenario to an inp I get the error "Object reference not set to an instance of an object." I downloaded the latest version of watergems today and tried again - same error. It only exports my junctions. Any help would be appreciated. 
 Thanks

Jesse Dringoli · Accepted Answer

Hi Taylor - the scenario name was the key. In the model you had sent, the active scenario was set to "Existing System" which does not exhibit the problem. When I switch to the one you just mentioned "MDD" within the "EST Rehab- Alternate 2" scenario, I get the same error when trying to export to EPANET. 
 The problem appears to be due to hydropneumatic tank HT-1, which is present in the scenario in question but inactive in the one you had set current when you sent the model. From my testing, it appears that this happens in any model that has a hydropneumatic tank. I will report this to our development team but in the meantime, you may need to approximate this element as a different element. H ydropneumatic tanks are not an available element type in EPANET itself so some assumptions must be made on export, and equivalent results cannot be expected in EPANET. If you are sending the INP file to someone who does not have WaterGEMS, be sure to mention this limitation and the following related article: What are the limitations of importing/exporting EPANET files? 
 As a workaround to be able to export the model, try morphing the hydropneumatic tank as a regular tank, and configure the diameter and elevations to be roughly equivalent (see "constant area approximation" mentioned here ).

Sushma Choure · Answer

Hello Taylor, 
 Thank you for uploading the model files, while exporting WaterGEMS model into EPANET format, if you choose No - use element ID's as reference and not use labels then model exports without any error. 
 
 The problem is with long labels of pipes, PRVs and patterns, apparently long labels are not supported by EPANET 2.XX.XX version, which can be seen in below screenshot. Once you export the model with option to choose export labels below user notifications are seen. 
 
 Workaround is to relabel the pipes, PRVs and pattern names and then export EPANET if you wish to use labels are reference, else you can choose to export IDs instead which would be a quick way.

Jesse Dringoli · Answer

Glad to help. To close the loop on this, I have reported the issue to our developers as Defect # 526919, to be resolved in a future release (to better handle this situation instead of the error). I have added a note about this to the related wiki article .

Exporting to INP error

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