An intelligent terminal device is provided for preventing mal-operation of a power equipment. The power equipment has safety devices, such as breakers, isolators or disconnectors. The intelligent terminal device includes a communication module, a display unit, an input/output (I/O) module, and a protection shell covering and protecting the communication module. The display unit is used to display a communication status and a status of an unlocking mode, which is switchable between a remote unlocking mode and an in-site unlocking mode. The I/O module provides power I/O and I/O of information of the status of the power equipment. The communication module is used to monitor the status of the power equipment and the safety devices, control actions of the safety devices, upload the status to a control device through a network; and in response to receiving an unlocking instruction from the control device, perform an unlocking procedure.