Your GPS unit can be re-programmed at any time so it is compatible with NZTM2000. The new Topo50 maps and coordinates come into effect from the end of September 2009.


Follow these steps to re-programme your GPS:


  1. Turn the GPS on. You can do this inside as you don’t need to acquire satellites to change settings.


  1. Press the Page button 3 or 4 times. This will bring up the “Menu” Screen.


  1. Scroll down to “Set up”, Press Enter.


  1. Scroll down to “Units”, Press Enter.


  1. In “Position Format”, (Press Enter to change), Select “User Grid”, Press Enter.


  1. In the window that comes up you can alter the Grid Reference settings.


    1. Longitude Origin, Set to E173 00.000

    2. Scale, Set to 0.9996000

    3. False E, Set to 1600000.0 – check the number of digits – you may need an initial zero – that is 01600000.0

    4. False N, Set to 10000000.0

  1. Select “Save”.


  1. This will bring you out to the “Units” page.


  1. Scroll down to “Map Datum”.


  1. Select “WGS84”.


The GPS unit will now collect positions of Easting and Northings in NZTM/Datum2000.


To go back to the old NZMG/GeoDatum49, change “Position Format” to “New Zealand”. This will set the datum to “Geod Datum 49”.


To reselect the new NZTM/Datum2000 Change “Position Format” toUser Grid” and “WGS84”and you will be good to go.