The chart licence belongs to the machine/system it was purchased. In this case the TZT2 system chart master holds the licence and it will share the licence with all those connected with it on the network including your new TZT3 unit. If the chart licence is older, you may have to downgrade the chart installed on the TZT3 chart card to the older version to unlock it. Alternatively, the chart licence can be upgraded (half normal cost) to the newest version.