Technical difference between surge arrestors and surge protestors
• Internal Monitoring Capabilities
It is the ability to identify internal failure quickly, and to activate remote alarm or light for indicating the failure. The surge arresters don’t have this quality whereas surge protectors are able to identify failure and to activate a remote alarm or light quickly.
• EMI/RFI filtering
The surge arresters don’t provide the facility of filtering EMI/RFI. However, the high quality surge protectors can do this job.
• Internal Fusing
Internal fusing is defined as protection of the equipment from overload current. This facility is also unavailable in surge arresters whereas you can protect your equipment from overload by using high quality surge protectors.
The design of surge arresters are based upon gapped MOV design. On the other hand, surge protectors are design by hybrid MOV.
• Interrupts power
Interrupts power and is also known as crowbar. This feature is available in surge arrestors; however, the surge protectors don’t have it.
Surge arresters have limited warranty whereas surge protectors have a warranty of at least of 5 years.
• Life Expectancy
Surge arresters are "use and throw away" type devices, and have limited life. However, surge protectors have a life of more than 25 years if they are sized appropriately.