Importing a project from WorksManager into TBC

Hello, I’m curious as to when I pull a project in from Worksmanager into TBC a screen pops up asking for me to indicate my coordinate sequence which, being in North America is Point, Northing, Easting and Elavation. I have three options to select from, they are: DMT (P,N,E,ELV), Control (P, N, E, ELV.), or Unknown (P, N, E, ELV.).

A source I have as reference who is pretty well versed with this says to use unknown, but can’t give a definitive reason as to why. Any clarity on this would be greatly appreciated!!

To further your understanding, I would recommend clicking on each one of these options and then clicking through the import point menu to see what all each of them changes (without actually importing the points). If you type F1 in TBC for the help and search “How Coordinate Quality for a Point is Displayed”, you will find that the Control vs Unknown setting are just two of the options for point quality in TBC, depending on how much you trust your data and how it was collected. One of the import points dialog boxes lets you choose your quality, and the Control (P, N, E, ELV.) versus the Unknown (P, N, E, ELV.) is just a preset. You can change the presets or define new presets. I was hoping to find a post about all this somewhere but can’t find it. Your next question will be about the grid-only checkbox, and I know there is a post about that :smiley:

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These options have little effect on most construction workfows. TBC has different states of points and those are mainly used in the Survey Data Processing functions (Traverse, Resection, Network, GPS Baselines etc.)

For example the other day I was talking through some things with a Surveyor and he had measured some points as As Staked points - he then set up a Total Station and resected from those As Staked points in the field and Trimble Access allowed him to do that. He downloaded the data into TBC and ran the survey processor and a number of his measured points from that resected station did not process and turned red in his point list. The reason being that TBC does not allow control calcs to be made from As Staked points - the points have to be Survey or Control quality to do that. So in TBC there is an option that allows you to promote an As Staked Point to a Survey Point so that those point copies can be used in the calculations engine.

Control Points have the highest quality
Survey Points are the second highest quality
Mapping / GIS Points are Mapping Grade Only (not used for control)
Unknown - are of unknown quality
As Staked are of Stakeout quality

Each has its place in the computations process.

All of the above can be used in surfaces without any issue

So for the Works Manager import - you just need to select the quality level that you are happy with for the points - the points come in in the correct location based on the coordinate order defined NEZ or ENZ etc. and will have the Point ID and Code but will then be assigned the appropriate quality that you selected.

You mentioned DTM - that is Surface quality i.e. a point you measured with a Rover or a total station to represent points on a surface.

What you select will only have an effect if those points are used for calculations to process raw survey measurements (Total Station measurements or GPS Baseline Measurements or Digital Level Loop Measurements etc.) into coordinates.

If they were coordinates provided to you by a Surveyor for Control then they are likely Control Quality

If they were points measured to establish new hubs for check in or additional stations for control then they are likely second order quality so Survey Quality

If they were Topo Shots then likely Survey Quality or Unknown (if they were measured in e.g. Walking Mode across the site on a GPS rover or with a pole that may not have been perfectly vertical at the time of measure then Unknown is likely the best classification or DTM

If they were points captured by a machine then I would set them to unknown

If you digitize them off a set of plans then likely Mapping quality not Survey quality

Matthew below also mentioned the Grid vs Grid Only vs CAD Points question. The differences between these are as follows

Grid Points are linked to the coordinate system / site calibration - if the coord system is modified or updated or a new site cal is added to the project, these types of points will update automatically and will be recomputed / repositioned in the new coordinate system (we do not recommend this for any construction data as the coord system / site cal for a project should never change after the project has started.

Grid only points - these are points that are not associated with the coordinate system - they have the ability to be Feature based for Feature Code processing and carry Feature Codes and Attributes like the Grid Points, but they do not move if the coord system changes or is updated - these are best for construction.

CAD Points - these are points that came in from DWG / DXF / DGN type files. They are not feature based and have limited functionality. You can convert CAD points if needed to Grid or Grid only points.

During import of CSV files you can select if the points are Grid or Grid Only points

When you run commands in TBC you can sometimes select whether the points being created are Grid or Grid Only points - in the Create Point command you cannot make that decision, however in other commands you can, especially in RPS commands.

Hopefully this answers the question

Thank you very much Alan. This was quite informative and will be helpful to me in the long run.