| Comment | A message is sent from the back office to all the machines on the network. When you present your card, the machine recognises the number and updates your balance with the amount you paid for online.
If the machine you tap is a gate, it will load your top-up and then deduct your journey cost and open the gate (but it will all seem like a single transaction).
If you're nervous about it, present it to a ticket machine and it will top it up instantly and die your new balance. |
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