Abstract: A system includes a valve (14) configured to operate a filling of a tank (11); and blocking device (15) that blocks access to the valve (14). The blocking device (15) is operated between a closing and an opening position by an actuator (20) governed by a wireless terminal (12). The wireless terminal (12) includes a transceiver (65) for sending a charging signal (WD) that includes a data signal portion (D) and a supply portion (W) carrying energy via electromagnetic induction, in particular a WPC (Wireless Power Consortium) signal. The blocking device (15) is configured for receiving electrical energy from the supply portion (W) to operate the actuator (20). The blocking device (15) also includes a control module (70) enabling operation of the actuator (20) according to the data signal portion (D) exchanged with a corresponding control module (60) of the wireless terminal (12).