Energy absorption/dissipation - This rating, given in joules, tells you how much energy the surge protector can absorb before it fails. A higher number indicates greater protection. Look for a protector that is at least rated at 200 to 400 joules. For better protection, look for a rating of 600 joules or more.

επίσης
Among the factors to consider when choosing a surge protector – how many outlets, the optimal cord length and options such as protection for a coaxial cable connection – perhaps the most important factor is the surge protector’s joule rating.

Surge-GroupA joule rating indicates how much energy the surge protector can absorb before it fails. The higher the number, the greater the protection provided. Keys to determining the amount of protection needed include the type and value of the equipment to be protected.


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Note added at 19 mins (2019-07-10 15:12:03 GMT)
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ή και βαθμονόμηση σε joules