A system (100) for monitoring a temperature of an electrical conductor of an electrical cable and including a temperature sensor unit (100a) and a transceiver unit (100b). The temperature sensor unit (100a) is located inside the first (semi)conductive layer and includes a micro-controller (120), a temperature sensor (110), an energy harvest sub-unit (140) and a wireless transmitter layer (130). The temperature sensor (110) is adapted to detect a first signal (S1) representing temperature of the electrical conductor and to supply the first signal (S1) to the micro-controller (120). The transceiver unit (100b) is located outside the first (semi)conductive layer and includes an energy transmitter (160) and a wireless receiver (150). The energy harvest sub-unit (140) is adapted to harvest electromagnetic power from the energy transmitter (160) and to provide electrical power to the micro-controller (120). The wireless transmitter (130) is adapted to being engaged with the wireless receiver (150) under the control of the micro-controller (120) to transmit a second signal (S2) converted from the first signal (S1) to the wireless receiver (150). The energy harvest sub-unit (140) and the wireless transmitter (130) are designed to have different working frequency.