Insulators are very important components in power systems, and their main function is to support conductors and prevent current leakage. The voltage can be roughly judged based on the condition of the insulator, which requires a comprehensive assessment of its appearance, sound, and any other accompanying phenomena. However, please note that observing the insulator alone cannot accurately determine the specific voltage value; this requires professional instruments for measurement. Below are some situations that may indicate the presence of voltage based on the performance of the insulator:

1. Appearance color: The surface of the insulator is usually coated with materials that indicate color. Under the influence of voltage, these indicator colors will change with the intensity of the voltage. Generally, the deeper the color change, the higher the voltage. However, this method is only suitable for qualitative judgment and cannot provide specific voltage values.

2. Discharge phenomenon: The air around the insulator will ionize under a strong electric field, resulting in discharge phenomena. If corona discharge or spark discharge is observed near the insulator, it usually indicates a higher voltage. The frequency and intensity of the discharge sound can also serve as a basis for judgment.

3. Insulator condition: If the surface of the insulator is dry, clean, and free of damage or cracks, it indicates that the voltage it bears may be light or within the normal range. Conversely, if there are stains, damage, or signs of aging on the surface of the insulator, it may mean that the voltage it bears is high or there is a potential fault.

4. Equipment operating status: If the power equipment is operating normally, the voltage borne by the insulator should match the rated voltage of the equipment. By observing the operating status and sound of the equipment, one can indirectly judge the voltage situation that the insulator is subjected to. However, this method requires rich experience and professional knowledge.

In summary, judging the voltage through the appearance, sound, and other performances of the insulator is only a preliminary method and cannot provide accurate values. To accurately know the magnitude of the voltage, professional voltage detection instruments must be used for measurement. In addition, operations and handling of high-voltage electricity should be carried out by professional electricians, and appropriate safety measures should be taken. Non-professionals should avoid direct contact and judgment of the voltage situation of high-voltage electrical equipment.