Brief introduction of surge protective device service conditions.

1. Frequency
Frequency range is from 47 Hz to 63 Hz a.c.

2. Voltage
The voltage applied continuously between the terminals of the surge protective device (SPD)
must not exceed its maximum continuous operating voltage UC.

3. Air pressure and altitude
Air pressure is 80 kPa to 106 kPa. These values represent an altitude of +2 000 m to -500 m,
respectively.

4. Temperatures
• normal range: –5 °C to +40 °C
NOTE This range addresses SPDs for indoor use in weather-protected locations having neither temperature nor
humidity control and corresponds to the characteristics of external influences code AB4 in IEC 60364-5-51.

• extended range: –40 °C to +70 °C
NOTE This range addresses SPDs for outdoor use in non weather protected locations.

5. Humidity
• normal range: 5 % to 95 %
NOTE This range addresses SPDs for indoor use in weather-protected locations having neither temperature nor
humidity control and corresponds to the characteristics of external influences code AB4 in IEC 60364-5-51.

• extended range: 5 % to 100 %
NOTE This range addresses SPDs for outdoor use in non weather protected locations.