A surge is when the voltage increases dramatically above the standard voltage provided by YVEA. Most homes have a 120/240-volt system. That means at the meter, the nominal voltage on one leg to ground is 120 volts, and leg to leg nominal voltage is 240 volts. A surge could be classified as when the voltage increases greater than 140 volts.
The MSA minimizes the amount and duration of the surge that comes in via the utility's electric system to a safe voltage that most appliances can tolerate. Most sensitive electronic equipment (i.e. televisions, stereos, computers, faxes, printers, etc.) may not tolerate that voltage and will require a second line of defense provided by a “point-of-use surge arrestor”. The surge protector passes the surge along from the device to the system ground. YVEA does not verify the integrity of your home’s grounding system.
It will not prevent flickering, outages, or dips in voltage. A dip is when the voltage goes below 120 volts. A dip in voltage can cause damage to equipment too. A meter socket surge suppressor will not protect your home from a direct lightning strike. All surge protection devices will burn out after repeated power surges.
The MSA has an indicator light tells you if the components are functioning. Without an indicator light, you have no knowledge if the protector is still functioning properly.