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主题:【原创】话说军规 / 工规与商规电脑的差异 -- 四月一日

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  • 家园 【原创】话说军规 / 工规与商规电脑的差异

    【原创】话说军规 / 工规与商规电脑的差异

    军规与工规电脑使用的料件与商用不同, 基本的差别在于对抗恶劣环境的部份, 主要的为宽温湿度, 防尘, 防水, 防盐雾, 防撞击与震动, 以及特殊需求的如重工规格的防高突波脉冲, 防雷击, 防 EMI 干扰, 防火等等, 还有就是高标准的 reliability / redundancy 要求. 这里先谈谈环境规格.

    工作环境温度 (Operating Temperature)

    一般商用机元件的工作温度为 0 ~ 70 度 C, 工规宽温为 -20 ~ 85 度 C, 军规依情况等于或高于工规. 由于 IC 本身的限制, 若要求系统能在更严苛的环境温度下工作, 一般是采取系统调适的解决方法, 比如说环境过冷时, 系统启动后先运行增温线圈, 再经过导热板或系统内空气传送到需要较高温度才能启动的组件, 待系统内部增温到零度以上再行触发主板启动.

    防尘 (dirt / dust proof / resistant)

    防尘处理用于工规是指用于工厂环境或户外应用, 也就是非 PC 指定的室内 (home and office / with air condition) 的 "舒适环境". 这个部份广的来说是在进风孔添加 air filter, 细的来说就要看所处环境的粉尘颗粒与系统内部的粉尘容许度 (dust tolerance) 和系统所需要的进风量 (一般与散热有关) 来设计. Air filter 可用如冷气机滤网, 泡棉, 不织布等材料, 若合并考虑抗盐雾或特殊环境 (如矿坑或火山口内的腐蚀性或易爆性气体) 会有所不同.

    防水 (water proof / resistant)

    一般常见的防水规范是 IP54 / IP65 / IP67 等, 细的还很多. 较简易的防水规范是防泼水 (splash), 也就是可以防止系统局部的泼水或溅水, 如下雨或打翻果汁等, 这个规格在较高档的商用笔记本即可达到要求. 简易的处理方法是在系统曝露在外的 device 进行设计, 如 NB 的 Keyboard, LCD 接缝与 button 做处理. 工厂或户外环境使用的 Workstation / Panel PC 一般是以 Touch Panel 或 全防护型的 Matrix Keyboard 来达成. 较为严苛的防水设计要计入耐水压值, 这个就不能以简单的方法达成 (用硅胶或橡胶垫圈抗不住 200M 的水压). 高耐压值的防水系统使用的机壳无法以拼装的方式达成, 必须使用如铝铸模一体成型的方式. 另外全防水设计要求机器能直接浸在水中运行, 这和半防水或局部防水又有不同. 由于 IC 的限制, 较高效能的 CPU 几乎不可能在没有透过空气散热的环境下工作, 所以一般使用 486 以下或是 PowerPC 等 RISC 做为运算核心. 防水的另一样特殊的部份在于 external connector 和 cable linkage. 一般使用圆形旋入式接头, 如附图.

    防盐雾 / 腐蚀性化合物

    用于船舶, 海岸, 海上钻油平台或观测站等的设备需要具备防盐雾的功能. 如果运算要求不高, 处理方式与防水类似. 若是系统需求较高, 如 586 以上必须开孔散热的就很麻烦, 要使用风扇的更是麻烦. 一般的克服方法是进风口加上过滤器以排除对系统有害的物质. 也有在主机外再包覆一台具备隔离效果甚至内部衡温的机箱 (车载式) 或护套 (便携式), 以达到所需要的要求. 军规的由于士兵的体能较佳, 也有放在如拉杆箱的防护内的. (士兵搬台三十公斤的机箱应该不成问题, 但让行业应用的工程师这么干就很难了.)

    防震动 / 冲击 (Vibration / Shock Proof)

    这个在 system configuration 必须考虑的. 由于工规或军用的应用方式较为特殊, 比如单兵背了台电脑在肩上做卧倒的冲击 (1.5 M / 1 ~ 1.5G / Operating), 或是装在军车上的电脑必须能在石子路上以高速跑, 若是一般的家用 PC 一定会给震散了, 更别说要保持工作状态, 特别是脆弱的组件如 HDD 之类的. 避震的方式很多, 依系统需求也有许多不同的解决方式. 如 HDD 避震架, Add-in Cards 压条, 基板悬吊式结构等等. 主板必须避免使用大颗的电解电容, 小型系统或 device 甚至有完成组装后打入硅胶固定的方式. (这个方法几乎可以达到完全避震, 缺点是无法维修.)

    防雷击, 防高 EMI 与防火

    特殊应用的电脑必须符合特殊规格, 如不受雷击干扰而能正常工作. 简单的系统设计是在透过 RS422/485 连结的 port 端加防护. 工规 / 军规的 EMI 环境要求与商用 / 家用的也不相同, 如进入高 EMI 环境工作的便携式笔记本或工作站不能一进去就不能开机. 防火应用亦同. 如果是属于简单数据的, 使用 programmable 单片机即可, 且单片机的抗环境能力高于 PC 组件甚多.

    关于前面帖子谈到的产品涉及国内某公司的不便多说, 呵呵, 拿工规 / 军规的项目经费去开发出个不军不商的产品的例子多了去了. 基本上以 PC-based 的组件可以达到的严格军规的系统规格上限在 Intel Pentium 166 / 430TX / PIIX4E 的组合以内, 再往上因为 IC 本身达不到要求, 必须以系统设计来克服商用组件的不足之处, 或是只能适应部份工规 / 军规要求. 即便是工规也有许多不同应用与级别的规范, 如简单的 EIA RS310C 或是更高的规格. OS 一般不会使用 "开机就要等半天 + 非法关机就会挂" 的 M$ Windows.

    附图: 防水 external connector / cable linkage

    点看全图

    点看全图

    元宝推荐:Highway,

    本帖一共被 2 帖 引用 (帖内工具实现)
    • 家园 以前的计算机要空调无尘

      计算机房还要穿拖鞋,就差带口罩手套了,是什么标准的?

    • 家园 实际情况也未必

      有很多达不到地方,凑合一也就过去了。毕竟现场环境一般都是恶劣的。

      WIN系列现在用的很多了,很多组态软件都是在WINXX下运行的。美国军方不是也用么。

      其实,从技术上说,没什么特别的,关键是很多东西没人去做,尤其是不挣钱的东西。

      • 家园 您误会了,这里讨论的是环境对硬件的要求, 您说的是软件

        给您看看我常用的工业标准http://www.cchere.net/article/506352

    • 家园 转贴我常用的环境规格工业标准

      National Electrical Manufacturer’sAssociation (NEMA) Standards250-1991, Enclosures for Electrical

      Equipment (1000 Volts Maximum)

      NEMA Enclosure Rating

      Enclosures may be tested to determine their ability to prevent the ingressof liquids and dusts. In the United States,equipment is tested toNEMA 250. Some of the more common

      enclosure ratings defined in NEMA 250 are as follows.General Locations

      _ Type 3 (Dust-tight, Rain-tight,

      or Ice-resistance, Outdoor enclosure):

      Intended for outdoor use primarilyto provide a degree of protection against rain, sleet, windblown,dust, and damage from external ice formation.

      _ Type 3R (Rain-proof, Ice-resistance,

      Outdoor enclosure): Intended for outdoor use primarily to

      provide a degree of protection against rain, sleet, and damage from external ice formation.

      _ Type 3S (Dust-tight, Raintight, Ice-proof, Outdoor enclosure):Intended for outdoor use primarily to provide a degree of protection against rain, sleet, windblown dust, and to provide for operation of external mechanisms when ice ladened.

      _ Type 4 (Water-tight, Dusttight,Ice-resistant, Indoor or outdoor enclosure): Intended for indoor or outdoor use primarily to provide a degree of protection against windblown

      dust and rain, splashing water,hose-directed water, and damage from external ice formation.

      _ Type 4X (Water-tight, Dusttight,Corrosion resistant, Indoor or outdoor enclosure): Intended for indoor or outdoor use primarily to provide a degree of protection against

      corrosion, windblown dust and rain, splashing water, and hose-directed water, and damage from external ice formation.

      Hazardous (Classified) Locations Two of the four enclosure ratings for hazardous (classified) locations are described as follows in NEMA 250:

      _ Type 7 (Class I, Division 1,Group A, B, C or D, Indoor hazardous location, Enclosure): For indooruse in locations classified as Class I, Division 1, Groups A, B, C or D as defined in the NEC and shall be marked to show class, division, and group. Type 7 enclosures shall be capable of withstanding the pressures resulting from an internal explosion of specified gases, and contain such an explosion sufficient that an explosive gas-air mixture existing in the atmosphere surrounding the enclosure will

      _ Type 9 (Class II, Division 1, Groups E, F or G, Indoor hazardous location, Enclosure): Intended for use in indoor locations classified as Class II, Division 1, Groups E, F and G as defined in the NEC and shall be marked to show class, division, and group. Type 9 enclosures shall be capable

      of preventing the entrance of dust.

      The above two NEMA ratings are now often misunderstood. For example, the above definition of Type 7 is essentially

      the same as that for explosion

      –proof. Therefore, when an approval

      agency approves equipment as

      explosion–proof and suitable for Class

      I, Division 1, the equipment automatically

      satisfies the Type 7 requirement;

      however, the agency does not require

      that the equipment be labeled Type 7.

      Instead it is labeled as suitable for

      Class I, Division 1. Similarly, Type 9

      enclosures would be labeled as suitable

      for Class II, Division 1.

      Hazardous Location

      Classification

      Hazardous areas in North America are classified by class, division, and group.

      Note

      The method of classifying locations as zones instead of divisions was introduced into the 1996 edition of the NEC as an alternate method, but it is not yet in use. The zone method is common in Europe and most other countries.

      Class: The Class defines the general nature of the hazardous material in the surrounding atmosphere.

      _ Class I—Locations in which flammable gases or vapors are, or may be, present in the air in quantities sufficient to produce explosive or ignitable mixtures.

      _ Class II—Locations that are hazardous because of the presence of combustible dusts.

      _ Class III—Locations in which easily ignitable fibers or flyings may be present but not likely to be in suspension

      in sufficient quantities to product ignitable mixtures.

      Division: The Division defines the probability of hazardous material being present in an ignitable concentration in the surrounding atmosphere.

      _ Division 1: Locations in which the probability of the atmosphere being hazardous is high due to flammable material being present continuously, intermittently, or periodically.

      _ Division 2: Locations that are presumed to be hazardous only in an abnormal situation.

      Group: The Group defines the hazardous material in the surrounding atmosphere.The specific hazardous materials within each group and their automatic ignition temperatures can be found in Article 500 of the NEC and in NFPA 497M. Groups A, B, C and D apply to Class I, and Groups E, F and G apply to Class II locations.

      The following definitions are from the

      NEC.

      _ Group A: Atmospheres containing

      acetylene.

      _ Group B: Atmospheres containing hydrogen, fuel and combustible process gases containing more than 30 percent hydrogen by volume, or gases or vapors of equivalent hazard such as butadiene, ethylene oxide,propylene oxide, and acrolein.

      _ Group C: Atmospheres such as ethyl ether, ethylene, or gases or vapors of equivalent hazard.

      _ Group D: Atmospheres such as acetone, ammonia, benzene, butane, cyclopropane, ethanol, gasoline, hexane,methanol, methane, natural gas,naphtha, propane, or gases or vapors of equivalent hazard.

      _ Group E: Atmospheres containing combustible metal dusts, including aluminum, magnesium, and their commercial alloy, or other combustible dusts whose particle size, abrasiveness, and conductivity present similar hazards in the use of electrical equipment.

      _ Group F: Atmospheres containing combustible carbonaceous dusts,including carbon black, charcoal, coal, or dusts that have been sensitized by other materials so that they present an explosion hazard.

      _ Group G: Atmospheres containing combustible dusts not included in Group E or F, including flour, grain,

      wood, plastic, and chemicals.


      本帖一共被 1 帖 引用 (帖内工具实现)
    • 家园 俺当年参加发射火箭那会儿,出过一个事.

      在现场测试时俺们所的一台电脑启动不了,后来发现是内寸条的问题,拔下来换了个槽就好了.麻烦在质量部门不依不饶,要俺解释原因,还要"举一反三".实际上这已经是市面上最贵的了,而且采取了一些加固措施,但主板,内存条毕竟都是进口的,我找谁去呀.晕.后来官司打到总师那,也没办法,不了了之.

      所以国内的那些军规之类只是对付些表面问题,深层问题其实并没办法.

    • 家园 讲个工业级鼠标的故事

      一个项目开箱验收, 按图索骥, 发现多了一个鼠标, 我偷偷地占为己有, 拿回去打游戏(嘿嘿), 那时候狂迷英雄无敌二.这个工业级的鼠标还真不错, 一.线长, 大概有三米长.我可以趴在床上点击鼠标控制桌子上的计算机二.寿命长, 天天咔咔地按动无数次,我的英雄无敌从二代到三代, 还打了六代, 中间还穿插了仙剑奇侠传, 殖民计划,大富豪等游戏.好象用了三年或者四年, 才觉得需要换新的了.后来买的鼠标, 用不来太久就得换, 谁让俺天天咔咔地折磨这只老鼠了di.

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