The rated working voltage of the indicator light is 220110, 48, 36, 24, 12, 6, 3 V, etc. Due to the limitation of the current level in the control circuit, and in order to extend the service life of the bulb, it is often adopted to add a current limiting resistor in front of the bulb or use two bulbs in series to reduce the working voltage.

Power indicator lights belong to the lighting industry and are subdivided into a category of indicator lights, which have been recognized by a large number of customers. The indicator lights on the front panel and power supply device of the system are used to indicate the power status of the system. The power button controls the power supply to the input system power device. The power button indicator light can provide information about the power status.