We have an old alarm system in the house, the panel is an Optima G3. Tonight the alarm box outside went off, no indication as to why on the panel. It wouldn't turn off by entering our code and so we've had to disconnect the alarm box. The system seems 'ok' apart from none of the sensors are working and I've no idea why - they've not been touched and were working ok earlier today. Any help or advice would be greatly appreciated!! If you can explain in very simple words it would be a great help - I don't really understand anything about how the system works!!