Hello,
Thank you for your question.
In FMB630 there is no option to set PIN. However, for Bluetooth there are two modes : visible and hidden.
When the device Bluetooth is set to be in hidden mode, no other devices will see it and it will be safe from unwanted connections.
Visible mode - is standart mode.
All device pairings can be done in configurator - global parameters - bluetooth settings.
Best regards