The surge protective devices (surge arresters, SPD) operation time may amount to 10 year, if comply to the followings requirements,

1. The electrical network voltage is in normal conditions (the voltage exerted in the module do not surpass millisecond level) and the discharge current (8/20us) exerted in the module do not surpass Imax (maximum discharge current).

2. The surge protective device cannot be installed in the acid and alkali, the salt mist, the multi- dust environment, and cannot be exposed to the sun and rain.

3. Normal temperature scope: -40 ℃ ~ +85 ℃
    Relative humidity: Under the room temperature is 30% ~ 93%
    Atmospheric pressure: (101.3-80) kPa (below elevation 2000m)