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36 PCB007 MAGAZINE I JULY 2019 is able to protect the electronic product from shock and vibration in the shipping. ΔV = 2/π*A*D * 10 -3 (Equation 1) The maximum shock force level along X, Y, and Z in the drop test is recorded in Table 5. The maximum ΔV calculated from Equation 1 is 17.09 along the Z-axis, which can be used as the criteria to judge whether the shock energy level for the packaged system is out of limits in transportation and transferring processes. The data maximum g-force from those two routes by train and sea were retrieved from the shock measurement device then the same computa- tion was done as previously for maximum en- ergy levels ΔV. The maximum acceleration re- corded by the device from the railroad route along the horizontal XY-direction was 20 g and vertical Z-direction was 35 g, which converts to 5.46 total energy. On the other hand, the maximum acceleration recorded by the device from the sea cargo route along the horizontal XY-direction was 13 g and vertical Z-direction was 11 g, which converts to 2.03 total energy. Comparing the total shock energy of railway and sea cargo to the maximum energy from the lab test indicates the package design and three design improvements were able to eliminate the contact interconnect problem and reduce the failure rate to zero. Finally, the temperature and humidity from the stickers in the packaging box and data measurement from the shock measurement device were all within the product testing re- quirement for product storage and operation, +40~-40°C and 30–95% RH to fulfill the product warranty mission time. Conclusion The contact interconnect problem of electronic accessories in the computer server system due to the severe shock in the trans- portation and transferring processes can be resolved through the following three ap- proaches: • Ensure hard Au plating thickness • Increase the damping plate area and thickness • Add the motherboard locking mechanism The redesign verification approach to com- pare shock energy from the field through two shipping routes to the lab test indicated that the total energy level from the lab drop test on the product is much larger than from real transportation and handling stresses so that the package design is able to protect the elec- tronic product from shock and vibration dur- ing the shipping and avoid the contact inter- connect failure totally. Table 5: Multiple corner-edge-face drop test for the product.