Dust level (the first X)0: no protection1: to prevent large solid intrusion2: to prevent the invasion of solid medium size3: prevent small solid into intrusion4: prevent solid objects greater than the entry of 1mm5: to prevent the accumulation of harmful dust6: completely prevent dust enteringWaterproof grade (second X)0: no protection1: the drops into the shell had no effect2: when the shell is tilted 15 degrees, water droplets drops into the shell had no effect3: water or rain from 60 degrees corner to the housing no effect4: liquid from any direction poured into the shell did not damage effect5: rinse with water without any harm6: can be used for the cabin environment7: in a short time immersion resistant (1m)8: in the long time of soaking under certain pressureShell protection grade (IP code) standards:1) by IEC (INTERNATIONAL ELECTROTECHNICAL COMMISSION) the IEC: International Electrotechnical Commission Standard IEC 529 – 598; 2) GB GB 700 - 86; 3) GB 4208.Shell protection grade (IP code) laboratory:0：沒有保護1：防止大的固體侵入2：防止中等大小的固體侵入3：防止小固體進入侵入4：防止物體大于1mm的固體進入5：防止有害的粉塵堆積6：完全防止粉塵進入防水等級(第二個X表示)0：沒有保護1：水滴滴入到外殼無影響2：當外殼傾斜到15度時，水滴滴入到外殼無影響3：水或雨水從60度角落到外殼上無影響4：液體由任何方向潑到外殼沒有傷害影響5：用水沖洗無任何傷害6：可用于船艙內的環境7：可于短時間內耐浸水（1m）8：于一定壓力下長時間浸水外殼防護等級（IP代碼）的標準有：1）由IEC（INTERNATIONAL ELECTROTECHNICAL COMMISSION）所起草國際防護和防水試驗標準：國際電工委員會標準IEC 529 – 598；2）國標GB 700 – 86；3）GB 4208等。外殼防護等級（IP代碼）實驗室：