399 series

      The 399 series are kinds of circuit protectors.Here you can get something about the features.First,it is designed for worldwide applications.Secondly,it reduces PCB space requirements.Thirdly,it has highly defined cut-off times.Fourthly,it has irreversible physical separation.Fifthly,it has low internal resistance.Sixthly,it has flame resistant encapsulated casing.
      Then is something about the operating criteria.Maximum continuous current: I_C   I_{operating max} x F_{T time lag}
Minimum fault current:I_Fault 3 x I_C;Maximum fault current:I_Fault 50A at 65VAC/DC.It is packaged with 000 (Tape/Ammopack (1400 pcs.)). The Base/Cap uses Brown Thermoplastic Polyamide PA 6.6, UL 94 V-0.The round pins use copper and Sn plated.The operating temperature ranges from -40  to +85 (consider de-rating).Then we introduce something about the stock conditions.The temperature is from +10 to +60 .The relative humidity is lower than 75 % yearly average,without dew and the maximum value for 30 days is 95 %.The vibration resistance comes next.It has 24 cycles at 15 min. each (EN 60068-6),10 - 60 Hz at 0.75 mm amplitude and 60 - 2000 Hz at 10 g acceleration.The lead pull strength is 10 N (EN 60068-2-21).The solderability is 260 , 3 s (Wave) and 350 , 3 s (Soldering iron).The unit weight is 0.60 g (approx.).