topic Re: Help witht Coordinates in Coordinate Reference Systems Questions

Help witht Coordinates

SamMason1 — Thu, 28 Apr 2022 14:49:21 GMT

Hi everyone

Can anyone make heads or tails with these coordinates? It is from a survey of a lot that I need to map into a BIM program as a site plan and I am deeply confused!
The distance between points is clear but the remainer (mainly how the coordinates are written) is quite unclear to me.

Thank you in advance !!

Re: Help witht Coordinates

curtvprice — Thu, 28 Apr 2022 15:43:31 GMT

No way to tell what the coordinate system for sure, you can only guess. I would try coordinate systems that are used in that particular area of the world. Better yet, ask the person you got this survey sheet from.

Re: Help witht Coordinates

MelitaKennedy — Wed, 04 May 2022 19:21:49 GMT

The (partial) definition is there in the Coordinates header: Lo 31. That's a South African coordinate reference system (CRS). It might be based on the Cape datum/geographic CRS or the current Hartebeesthoek94 CRS. We do a weird workaround to support these coordinates because the axes are south-west (or maybe west-south order) rather than our default of east-north.

Try entering them as they are using projected coordinate systems-national grids-south africa-Hartebeesthoek94 Lo31 and see how they work. If they appear to be flipped, try the (E-N) version instead.

Melita