Issue with FLOWDIRECTION being automatically added as network attribute to electric UN

[Isaac_King]

I am encountering some undesirable behavior using the electric essentials package (UNv7) with Pro 3.3.

This package includes FLOWDIRECTION as an OOTB attribute but NOT as a network attribute. Unfortunately, when I apply my asset package, this is being set as a network attribute in the resultant UN - and creating some terminal connection issues in secondary lines. 

I have deleted the attribute from my asset package and reapplied, and somehow the attribute reappears and is set as a network attribute again in a newly created UN. I am not able to delete the attribute from ElectricLine feature class because it is set as a network attribute.

I'm stuck in a very annoying loop here and hoping someone like @RobertKrisher or @MikeMillerGIS may have a suggestion for a fix.

Thanks!

[RobertKrisher]

The FlowDirection attribute is a system field that was added to the utility network at v7. It shouldn't affect tracing unless you specify the 'use digitized direction' option in tracing, which has limited/no application in an electric network.

v7 / upgrade history help: Utility network upgrade history—ArcGIS Pro | Documentation

v7 blog: What's New for the ArcGIS Utility Network with the 2024 Network Management Release (esri.com)

digitized direction help: Configure a trace—ArcGIS Pro | Documentation

digitized direction blog: Introducing Tracing Using Digitized Direction in the Utility Network (esri.com)

[Isaac_King]

Thanks, @RobertKrisher 

It is not impacting tracing (yet). The issue I am encountering is some secondary line segments creating a Line Feature has Invalid Terminal error. This is happening when my fromterminal attribute is set to 2wXFR:Secondary. The error goes away if I clear the fromterminal value and apply the same to the toterminal attribute, but this is obviously not correct for a radial secondary being fed by a transformer.

Any ideas?

[RobertKrisher · Accepted solution]

Your problem is that you assumed that the transformer was going to be at the first vertex of the line when it is in fact at the last vertex of the line. It is 100% acceptable for the transformer to be at the last vertex of the line because the utility network doesn't rely on the digitized direction to control flow, and electrical networks don't rely on the digitized direction of lines to control flow/tracing. If we did, then you wouldn't be able to backfeed a circuit by opening a switch because all the medium voltage lines would be drawn in the wrong direction.

The flowdirection is unrelated to that error, and even if you were to deploy a v6 network without the attribute you would still have the error. The problem is that you have populated the fromdeviceterminal with the terminal id of the device at the todeviceterminal position of the line. Remember that fromdeviceterminal and todeviceterminal refer to the device at the first vertex (from device) and the last vertex (to device) of the line, and not related to the flow of the network (i.e. which device is upstream).

[Isaac_King]

I just learned something I didn't know. Thanks, Robert! Hope you're doing well.

[RobertKrisher]

Doing well. I thought we tidied up the online documentation to be more explicit about from/to device terminal not being related to flow or flow direction, but it looks like we've still got some work to do on that front.