The absolute humidity in the Totech dry storage cabinets lies at a temperature of 20°C and <2% RH with less than 0,35g/m³. Under these conditions no cathode reaction and with this also no oxidation can take place. In the humidity protection bags packed under vacuum is with a rest pressure of ca. 6mbar between 0.1 und 0.06g vapour per m³. When the bags are filled with nitrogen, either a means of oxidation nor an electrolyte are available and oxidation is impossible. In the Standard-Dry Storage Cabinets Totech maintains for 24 hours on average a vapour pressure of <0.95mbar, in a humidity protection bag with a rest pressure of <6mbar the vapour pressure is <0.15mbar. Both systems, dry storage cabinet and humidity protection bag, protect in a reliable and effective way from diffusion. With storage periods of more than 5 years Totech recommends a combination of the two systems. The storage of humidity protection bags with nitrogen present components in a simple dry storage cabinet with 5% RH. Decisive with the bags, however, is that the construction of the bags is mechanically stable and shows a very small percentage of diffusion. The IPC/JEDEC-STD033B.1 demands a diffusion percentage (MVTR) of less than 0.002g/100in² in 24 hours with 40°C. This demand is only met by bags which have a strength of 150µm. 90µ-bags have a substantially higher diffusion percentage and are therefore not suitable. The Totech Bags remain below the maximum value as laid down in the IPC in a multiple. The MVTR is 0.0006g/100in².
Productronica A3/234
eppe432
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