Power over-voltage protector 
The main function of overvoltage protector is to monitor the power supply voltage of the power grid. The overvoltage, overvoltage, undervoltage, surge and short circuit automatic protection can protect the electrical lighting lamps from being burned, ignited and burned by the grid voltage or the abnormal input power supply, and effectively protect the safety of equipment and life and property. There are multiple protections, self-protection at high voltage, stable operation at low voltage, and fast action response.
Lightning arrester  
Surge protector, also known as lightning arrester, is mainly a safety protection device for various electronic equipment, instrument communication and street lamp lighting electronic. Its function is to limit the instantaneous overvoltage entering the power line and signal transmission line within the voltage range that the equipment or system can withstand, or to discharge the strong lightning current into the ground to protect the protected equipment or system from impact. Lightning arresters ‘ or ‘ overvoltage protectors ‘ are abbreviated as SPD. The role of surge protectors is to limit the instantaneous overvoltage entering the power line or signal transmission line to the voltage range that the equipment or system can withstand, or to discharge strong lightning currents into the ground to protect the protected equipment or system from shock damage.
Difference between the two 
Overvoltage protector has no effect on lightning, and arrester is not sensitive to overvoltage. Overvoltage refers to the supply voltage is higher than the equipment can withstand the voltage limit, such as operating overvoltage, light load overvoltage during trough period, or accident overvoltage. Overvoltage will damage electrical appliances, ‘ overvoltage protector ‘ is to prevent this kind of overvoltage damage. 
 
Lightning arrester is the equipment to prevent lightning disasters. Lightning and overvoltage are different. Lightning voltage is very high, and the damage caused by lightning is different from that caused by overvoltage. The disasters caused by lightning are breakdown and destruction. Lightning arrester is the equipment that provides the outlet for lightning. Both of them have the effect of suppressing overvoltage to protect electrical equipment. 
 
In general, the over-voltage protector is used to protect the power-frequency over-voltage. The so-called power-frequency over-voltage usually breaks out in the course of utilization. For example, when the arc is not zero when the switch is disconnected, there will be over-voltage. When the circuit is disconnected, due to the different impedance of the circuit wave, the over-voltage of the superposition of the voltage reflection wave breaks out. These over-voltages are power-frequency over-voltages, and the frequency of the voltage waveform remains unchanged at 50 Hz as usual. 
 
Lightning arrester is to protect lightning overvoltage, the hand-held device is damaged by lightning instantaneous high voltage. The front end of this kind of overvoltage waveform is steep and the frequency is high, but the follow-up current is very small. Lightning arrester can discharge the peak value of lightning wave to ensure the electrical comfort behind it. Usually, the lightning arrester is broken under the abnormal sign, and it is released to the earth when it passes through the lightning high voltage. The arrester does not act as a lightning conductor, if the lightning strikes the transmission line.When the lightning overvoltage can flow through the distribution assembly with the transmission line flowing to the transformer, the arrester discharges and the stop distribution assembly is damaged. 
The difference is that the protected object is not the same, there are also differences in the use of scenarios, lightning arrester is mainly lightning protection equipment, instrument communication, street lighting electronics are not damaged by lightning current and voltage.