Hello, this situation may require a little backstory to get the full context so please bear with me (Equipment Used: TDC600, Trimble Connect, Trimble Terraflex, R2, and Tornado Pole).
I received an AutoCAD DWG file from a surveying company pertaining to a project that I was working on for a client. The coordinate system assigned in the AutoCAD file was GA83-WF (NAD 83 Georgia State Planes, West Zone, US Foot). I was tasked with putting together a utility layout in AutoCAD Map, and then steak the locations of the light poles. We were aware that Trimble Connect does not currently accept NAD 83 as a datum reference, so from AutoCAD we exported our light poles into a shapefile with a coordinate conversion to WGS 1984. We then imported the resulting shapefile into a Trimble Map Workspace that was setup in WGS 1984. We started to locate our light poles, and we began to notice that the poles were consistently 3' due South East off target.
So since our light pole points were not lining in as they were laid out in our AutoCAD Drawing, we decide to go to a known reference point. In our case this was a property pin that the surveying company picked up and had in their AutoCAD file. We performed the same workflow as before, we exported that property pin point from AutoCAD to a shapefile (converted to WGS 1984), imported that property pin point into a Trimble M.W.S. setup in WGS 1984, and began the locating process. We walked to the location of the property pin (we could visibly see the pin), and find the point the TDC600 is telling us the pin is located at. We are again about 3' due South East of the actual location of the property pin.
I then tried to export the property pin point to NAD 83 (2011) and then import it into a NAD 83 (2011) M.W.S., but we still did not end up on top of the property pin (we were about 1' due South East off of the actual property pin). We tried a few other methods of exporting from AutoCAD and importing into Trimble Connect, but none of them were putting us on top of the property pin. I then had the idea to export the property pin point from AutoCAD to WGS 1984 and import that into a Trimble M.W.S. using NAD 83 (2011). We then begin to locate again, and we actually landed on top of the property pin. We export the rest of our light poles using this same methodology and they seem to be falling onto the locations that we designed in the AutoCAD file.
What is the workflow that Trimble recommends, when you are using a base file to work off of that is not in a datum that Trimble Connect supports?
(The image attached below is a diagram displaying what we saw in the field)
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Brandon Connelly
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