Surge Protection is very important to any electronic equipment. Here is a brief description of how surge protectors work:

Generally you have a device called an MOV (metal oxide varistor). It is inside a surge protector strip or console. The MOV is in parallel with the voltage supplied to the outlets of the surge protector. These MOVs are also attached to the ground plug of the unit. When voltage is at normal levels, the MOV’s have a high resistance to the voltage (this keeps the path from the line voltage from the ground line). Once a certain voltage level is reached, the MOV conducts. This allows a large amount of current to pass through it, lowering the voltage back to normal levels. The MOV only diverts surge current, allowing the normal current to keep the equipment being protected to operate normally.

Note: Surge Protectors only work if the circuit they are plugged into is properly grounded.

• Clamping voltage:  the voltage level at which the MOVs operate. There are generally 3 levels: 330,400 and 500 volts -- the lower the more sensitive. 
• Joule ratings: the amount of energy a unit can dissipate before it fails --the higher the better. 
• Indicator light: tell you if your surge protector is operating correctly. If you blow an MOV and there is no indication, your unit may operate but will not provide surge protection. 
• Phone jack surge protection: use if you are using a modem for your computer. (Any cable bringing a signal into your house or business can bring in a surge.) 
• UL rating: Underwriters’ Laboratories is a non-profit organization that test electronics products for their safety. 
• Indicator light: indicate that your surge protector is operating correctly. If one of the MOV fails, the light will extinguish. If there is no indicator light and one of the MOVs fail, your unit may appear to work properly but it will not provide any surge protection.

Note: Even if the unit has all these features, no unit is 100% effective. Do your own research and find a unit that works for you and your application.