The utility model provides a large power supply transformer folder with sensor is put in optic fibre method - amber office, belongs to the electrical equipment field. It has been solved and has been installed inside the large power supply transformer, has been used for detection office and puts optic fibre method - amber office of bringing out ultrasonic signal and put the sensor and can arouse that the inside electric field of large power supply transformer changes, influence the problem that the large power supply transformer moved. The utility model discloses a sensor is put in large power supply transformer folder and optic fibre method - amber office, and optic fibre method - amber office puts the sensor and passes through epoxy and fix at the angle of large power supply transformer folder inboardly, has realized that optic fibre method - amber office puts the sensor and put in the outside inside office of the large power supply of detection transformer of large power supply transformer and bring out ultrasonic signal, can not arouse basically that the inside electric field of large power supply transformer changes, can guarantee the steady operation of large power supply transformer. The utility model is suitable for an inside office of detection large power supply transformer puts and brings out ultrasonic signal.