900211-05
1． 什么是dcs？
dcs是分布式控制系统的英文缩写（distributed control system），在国内自控行业又称之为集散控制系统。
2． dcs有什么特点？
dcs是计算机技术、控制技术和网络技术高度结合的产物。dcs通常采用若干个控制器（过程站）对一个生产过程中的众多控制点进行控制，各控制器间通过网络连接并可进行数据交换。操作采用计算机操作站，通过网络与控制器连接，收集生产数据，传达操作指令。因此，dcs的主要特点归结为一句话就是：分散控制集中管理。
4． dcs的控制程序是由谁执行的？
dcs的控制决策是由过程控制站完成的，所以控制程序是由过程控制站执行的。
5． 过程控制站的组成如何？
dcs的过程控制站是一个完整的计算机系统，主要由电源、cpu（中央处理器）、网络接口和i/o组成。
日常维护
1 过程通道故障：过程通道故障出现最多的是i/o卡故障。i/o卡故障一般的判断与处理：通过系统诊断，更换通道或通过更换备用件处理，至于其内部元件老化或是其他原因造成的损坏，一般控制人员不好判断。i/o卡的检修一般是由厂家处理，目前的热控检修人员的手段还不能达到像检修常规仪表那样检修。而且生产厂家的i/o卡件已制造成一体化的趋势，这样只能购买备件。好在这类故障只是在调试阶段出现较多，正常运行中出现几率很低。一次元件或控制设备出现故障有时不能直接被操作员发现，只有异常或报警后才通知热控人员处理。这样对检修人员和运行人员的素质要求就要提高，运行人员要详细介绍故障前后的状态便于热控检修人员能够快速、准确地处理缺陷，减少故障的扩大化，另外许多dcs厂家在产品宣传上都支持卡件热拨，做为控制人员，在运行中更换卡件时一定要做好安全防护措施否则会引起系统变化或负荷变化，尤其数字量卡件。
2 对于操作员站死机无论国产与进口设备都有相关的报道，那么究其原因比较多，硬盘或卡件故障，冷却风扇负荷过重等等，有时会发生人为操作现象，一般在修改控制逻辑下装软件重启设备或强制设备保护信号时，最易发生操作事件，轻则设备异常，重则易造成设备停运后果非常严重；对死机后重启，不同厂家的启动时间不同，少则几十秒，多则几分钟，人为该操作发生的故障在热工专业中的不安全事件中占有很大比例，在操作中尤为引起高度重视，减少人为故障。
3球标操作不正常，一般是由于机械装置长期工作、老化、污染、点通断不可靠、电缆插件不牢等这样的就需要换检查即可。
4控制操作失灵：是由于球标的操作信号没有正常改变过程通道的状态，造成操作失效，这是2个方面造成的，一个方面是软件缺陷，另一方面是硬件本身故障的状态针对这样的缺陷通常做法检查过程通道功能正常后，再检查操作远必要时进行重起初始操作。
5 对于薄膜键盘主要是键盘接触不良信号电缆松动或主机误动键盘或启动不完整都可以导致其功能不正常应用针对不同情况处理。
6打印机不工作一般是由于配置的原因，这样的故障应检查打印机的设置及其硬件是否正常进行处理。报表软件功能不强主要表现在由于打印机打印报表和soe等造成死机，或者打印机的soe记录时问与实际情况不符；soe打印浏览后不能返回历史曲线；soe时间顺序不一致有时偏差很大，这会延误事故分析的进展时，有时还会误导分析方向，soe问题既与系统设计不合理，soe点没完全集中在一个dpu上的有关，也与系统硬件及软件设计考虑不周有关。这种故障的出现，通过分析认为这主要是对电厂的总体方面考虑的不太完美，在小的方面还不够仔细会出现这样那样的故障，针对这种情况要认真对待，不放过蛛丝马迹，与厂家认真研究提出问题进一步完善，让该系统更好地为生产服务。
7 电源故障：电源故障问题较多，保险配置不合理，备用电源不能自投，电源波动引起保护误动及接插头接触不良易造成无电源。针对电源故障处理相对比较容易。首先，认真核对保险的配置及容量，真正起到保险的作用；其次，ups的配备很重要，它可以在电源波动时也能保证系统正常供电，而且要考虑冗余和备用问题。
8 干扰造成的故障：对于干扰主要是接地问题，备用电源的切换和大功率的无线通信设备如手机、对讲机等。另外还有dcs系统的干扰信号可能由本身造成的。那么对于dcs系统的接地问题越来越引起人们的重视，尤其在电力行业，大功率电器设备的启动和停止都会干扰dcs的控制信号，造成不必要的故障。为了防止干扰信号串入系统，严格执行屏蔽和接地要求和方式，信号线远离干扰源，同时采取防电源波动措施。主/从过程处理机之间在机组运行时，除非万不得以，尽量不要人为切换，已防产生干扰，如必须切换，应采取措施，先将控制切手动，以免对机组运行工况产生影响。对电子设备问、工程师站等重点部位，应绝对禁止使用大功率无线电通信设备
reman fanuc power supply a06b-6087-h126 1 year warranty w/core $1745
refurbished fanuc spindle motor, mod# a06b-1003-b200, w/ 1 year warranty
refurbished fanuc spindle motor, mod# a06b-0754-b400#3000 w/ 1 year warranty
refurbished fanuc servo motor, model# a06b-0514-b505#7008, with 1 year warranty
refurbished fanuc servo motor, model# a06b-0512-b574#7008, with 1 year warranty
refurbished fanuc servo motor, model# a06b-0501-b005#7008, with 1 year warranty
ref # 7761302 1996 mori seiki sl-25-sy, 32" swing, 2.6" bar cap, fanuc 16
reduced price- victor tns3h cnc lathe, 12" chuck, fanuc ot control - see video
reduced- mori-seiki partner l-200v cnc vertical turning center - lathe, fanuc
reconditioned fanuc16 main cpu board a16b-3200-0010 with daughter boards
reconditioned fanuc16 main cpu board a16b-2200-0900 with daughter boards
reconditioned fanuc sub-a cpu board a16b-2201-0310 with daughter boards
reconditioned fanuc spindle amplifier ( a06b-6111-h006#h550 )
reconditioned fanuc spindle amplifier ( a06b-6111-h006#h550 )
reconditioned fanuc spindle amplifier ( a06b-6102-h222#h520 )
reconditioned fanuc spindle amplifier ( a06b-6088-h230#h500 )
reconditioned fanuc spindle amplifier ( a06b-6064-h305#h550 )
reconditioned fanuc spindle amp board ( a20b-1004-0600 )
reconditioned fanuc spindle amp board ( a16b-2201-0010 )
reconditioned fanuc spindle amp board ( a16b-2100-0070 with a16b-2201-0440 )
reconditioned fanuc spindle amp board ( a16b-2100-0030 )
reconditioned fanuc spindle amp ( a06b-6122-h100#h570 )
reconditioned fanuc spindle amp ( a06b-6122-h045#h570 )
reconditioned fanuc spindle amp ( a06b-6121-h015#h550 )
reconditioned fanuc spindle amp ( a06b-6121-h011#h550 )
reconditioned fanuc spindle amp ( a06b-6111-h022#h550 )
reconditioned fanuc spindle amp ( a06b-6111-h011#h550 )
reconditioned fanuc spindle amp ( a06b-6104-h226#h520 )
reconditioned fanuc spindle amp ( a06b-6104-h111#h520 )
reconditioned fanuc spindle amp ( a06b-6102-h106#h520 )
reconditioned fanuc spindle amp ( a06b-6078-h311#h500 )
reconditioned fanuc spindle amp ( a06b-6078-h306#h500 )
reconditioned fanuc spindle amp ( a06b-6078-h211#h501 )
reconditioned fanuc spindle amp ( a06b-6078-h211#h500 )
reconditioned fanuc servo drive ( a06b-6090-h003 )
reconditioned fanuc servo amplifier ( a06b-6127-h209 ) replaces a06b-6124-h209
reconditioned fanuc servo amplifier ( a06b-6114-h105 )
reconditioned fanuc servo amplifier ( a06b-6112-h006 # h550 )
reconditioned fanuc servo amplifier ( a06b-6096-h208)
reconditioned fanuc servo amplifier ( a06b-6096-h206 )
reconditioned fanuc servo amplifier ( a06b-6096-h202 )
reconditioned fanuc servo amplifier ( a06b-6090-h244 )
reconditioned fanuc servo amplifier ( a06b-6085-h104 )
reconditioned fanuc servo amplifier ( a06b-6085-h102 )
reconditioned fanuc servo amplifier ( a06b-6079-h291 )
reconditioned fanuc servo amplifier ( a06b-6079-h209)
reconditioned fanuc servo amplifier ( a06b-6079-h208)
reconditioned fanuc servo amplifier ( a06b-6079-h207 )
reconditioned fanuc servo amplifier ( a06b-6079-h206 )
reconditioned fanuc servo amplifier ( a06b-6079-h205)
reconditioned fanuc servo amplifier ( a06b-6079-h201 )
reconditioned fanuc servo amplifier ( a06b-6066-h008 )
reconditioned fanuc servo amplifier ( a06b-6058-h333 )
reconditioned fanuc servo amp module ( a06b-6114-h207 )
reconditioned fanuc servo amp board ( a16b-2201-0020 )
reconditioned fanuc servo amp ( a06b-6127-h207 )
reconditioned fanuc servo amp ( a06b-6124-h106 )
reconditioned fanuc servo amp ( a06b-6124-h105 )
reconditioned fanuc servo amp ( a06b-6124-h102 )
reconditioned fanuc servo amp ( a06b-6117-h202 ) replaces a06b-6114-h202
reconditioned fanuc servo amp ( a06b-6114-h302 )
reconditioned fanuc servo amp ( a06b-6114-h205 )
reconditioned fanuc servo amp ( a06b-6096-h208 )
reconditioned fanuc servo amp ( a06b-6096-h201 )
reconditioned fanuc servo amp ( a06b-6096-h106#ra )
reconditioned fanuc servo amp ( a06b-6096-h106 )
reconditioned fanuc servo amp ( a06b-6096-h104 )
reconditioned fanuc servo amp ( a06b-6090-h234 )
reconditioned fanuc servo amp ( a06b-6090-h008 )
reconditioned fanuc servo amp ( a06b-6089-h209 )
reconditioned fanuc servo amp ( a06b-6079-h207 )
reconditioned fanuc servo amp ( a06b-6079-h201 )
reconditioned fanuc servo amp ( a06b-6058-h251 )
reconditioned fanuc servo amp ( a06b-6058-h226 )
reconditioned fanuc servo amp ( a06b-6058-h203 )
reconditioned fanuc profibus master pcb ( a20b-8100-0430 )
reconditioned fanuc power supply module ( a06b-6091-h130 )
reconditioned fanuc power supply ( a06b-6120-h100 )
reconditioned fanuc power supply ( a06b-6120-h030 )
reconditioned fanuc power supply ( a06b-6120-h018 )
reconditioned fanuc power supply ( a06b-6110-h030 )
reconditioned fanuc power supply ( a06b-6110-h006 )
reconditioned fanuc power supply ( a06b-6087-h137 )
reconditioned fanuc power supply ( a06b-6087-h130 )
reconditioned fanuc power supply ( a06b-6087-h126 )
reconditioned fanuc pcb board for lcd touch screen ( a20b-8100-0400 )
reconditioned fanuc o control master ( a20b-1004-0260 )
reconditioned fanuc motor ( a06b-0373-b688#7008 ) same as a06b-0373-b688#0008
reconditioned fanuc mdi board ( a20b-1000-0851 )
reconditioned fanuc master board ( a16b-1010-0331 )
reconditioned fanuc master board ( a16b-1010-0210 )
reconditioned fanuc master board ( a16b-1000-0200 ) with ( a20b-1001-0640 ) mmc
reconditioned fanuc main cpu with daughter cards (a16b-3200-0190 )
reconditioned fanuc main cpu board a16b-2201-0300 with daughter boards
reconditioned fanuc main cpu ( a16b-3200-0330 ) with daughter cards
reconditioned fanuc main cpu ( a16b-3200-0110 ) with daughter cards
reconditioned fanuc main cpu ( a16b-3200-0060 ) with daughter cards
reconditioned fanuc lcd touch screen ( a02b-0259-c212 )
reconditioned fanuc lcd pcb board ( a20b-2100-0240 )
reconditioned fanuc i/o psu board ( a16b-2202-0980 ) with a20b-1005-0420 p/s
reconditioned fanuc i/o ( a16b-2203-0070 ) with a20b-1005-0421 p/s
reconditioned fanuc from/sram module 8mb/2mb ( a20b-2902-0090 )
reconditioned fanuc cpu module ( a20b-3300-0240 )
reconditioned fanuc cpu card dram ( a20b-3300-0107 )
reconditioned fanuc cpu card dram ( a20b-3300-0106 )
reconditioned fanuc a06b-6090-h244 servo amplifier
reconditioned fanuc a06b-6090-h006 servo amplifier
reconditioned fanuc a06b-6066-h008 servo amplifier
reconditioned fanuc a06b-6050-h004 servo unit
reconditioned fanuc 21 main cpu ( a16b-3200-0270 ) with daughter boards
reconditioned by fanuc servo motor ( a06b-0166-b088 )
reconditioned by fanuc servo motor ( a06b-0143-b675)
reconditioned by fanuc servo amp ( a06b-6117-h207 ) replaces a06b-6114-h207
reconditioned by fanuc ( a16b-1010-0280 ) master pcb
recondition power supply module a06b-6087-h130
recondition power supply module a06b-6087-h126
recondition power supply module a06b-6087-h115
recondition fanuc spindle amplifier module a06b-6092-h226#h500
recondition fanuc spindle amplifier ( a06b-6102-h230#h520