MVME-51105E-2163

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描述

MVME-51105E-2163

DCS是一种“分散式控制系统”,而PLC(可编程控制器)只是一种控制“装置”,两者是“系统”与“装置”的区别。系统可以实现任何装置的功能与协调,PLC装置只实现本单元所具备的功能。
在网络方面,DCS网络是整个系统的中枢神经,它是安全可靠双冗余的高速通讯网络,系统的拓展性与开放性更好。而PLC因为基本上都为个体工作,其在与别的PLC或上位机进行通讯时,所采用的网络形式基本都是单网结构,网络协议也经常与国际标准不符。在网络安全上,PLC没有很好的保护措施。我们采用电源,CPU,网络双冗余。
DCS整体考虑方案,操作员站都具备工程师站功能,站与站之间在运行方案程序下装后是一种紧密联合的关系,任何站、任何功能、任何被控装置间都是相互连锁控制,协调控制;而单用PLC互相连接构成的系统,其站与站(PLC与PLC)之间的联系则是一种松散连接方式,是做不出协调控制的功能。
DCS在整个设计上就留有大量的可扩展性接口,外接系统或扩展系统都十分方便,PLC所搭接的整个系统完成后,想随意的增加或减少操作员站都是很难实现的。
DCS安全性:为保证DCS控制的设备的安全可靠,DCS采用了双冗余的控制单元,当重要控制单元出现故障时,都会有相关的冗余单元实时无扰的切换为工作单元,保证整个系统的安全可靠。PLC所搭接的系统基本没有冗余的概念,就更谈不上冗余控制策略。特别是当其某个PLC单元发生故障时,不得不将整个系统停下来,才能进行更换维护并需重新编程。所以DCS系统要比其安全可靠性上高一个等级。
系统软件,对各种工艺控制方案更新是DCS的一项最基本的功能,当某个方案发生变化后,工程师只需要在工程师站上将更改过的方案编译后,执行下装命令就可以了,下装过程是由系统自动完成的,不影响原控制方案运行。系统各种控制软件与算法可以将工艺要求控制对象控制精度提高。而对于PLC构成的系统来说,工作量极其庞大,首先需要确定所要编辑更新的是哪个PLC,然后要用与之对应的编译器进行程序编译,最后再用专用的机器(读写器)专门一对一的将程序传送给这个PLC,在系统调试期间,大量增加调试时间和调试成本,而且极其不利于日后的维护。在控制精度上相差甚远。这就决定了为什么在大中型控制项目中(500点以上),基本不采用全部由PLC所连接而成的系统的原因。
模块:DCS系统所有I/O模块都带有CPU,可以实现对采集及输出信号品质判断与标量变换,故障带电插拔,随机更换。而PLC模块只是简单电气转换单元,没有智能芯片,故障后相应单元全部瘫痪。
现在高端的PLC与DCS的功能已经差不多,DCS对网络和分布式数据库还要定时扫描有较强的功能,同时对运算和模拟量的处量比较拿手。
PLC还分大、中、小、微PLC,其中微型的只卖几百块到2000块,点数也好少,大型的可以带数千点,运算能力与DCS差不多,但对多机联网功能较弱。现在两个技术平台都差不多,只是重点不一样。

产品承诺:
保 证 全新原装进口,
保 证 安全准时发货,
保 证售后服务质量,
优势价格,大量现货。

主营DCS系统配件
机器人系统配件
大型伺服系统配件
品牌:ABB   ,AB  ,GE,FOXBORO,本特利,英维思,伍德沃德,西屋,瑞恩,施耐德,西门子,摩托罗拉,安川。力士乐。ACSO,横河等进口品牌。 专业销售进口DCS  PLC系统备件模块
Triconex Siemens Yaskawa ABB GE Ovation AB Foxboro Motorola Schneider XYCOM KUKA
  专业销售进口DCS  PLC系统备件模块 15天包退换 一年质保 大量现货  国内实力库存商家

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专业销售进口DCS  PLC系统备件模块

PLC模块,可编程控制器,CPU模块,IO模块,AI模块,通讯模块。AB/施耐德/ABB/GE/本特利/西屋/英维斯/霍尼韦尔/黑马/FU克斯波罗

15天包退换 一年质保 大量现货  国内实力库存商家


选择深圳长欣,选择放心,售后无忧大量现货,当天顺丰发货!
主营:本特利,英维思,伍德沃德,福克斯波罗、西屋、瑞恩、施耐德莫迪康、ABB、AB、西门子、摩托罗拉、GE发那科、安川、博世力士乐,ACSO,力士乐等各大品牌的DCS系统配件,机器人系统配件,大型伺服系统备件。

先介绍几点经验。
1、先通读一遍“系统手册”(不管能不能看懂,先了解个大概,以便学习编程时查找);
2、由位控逻辑入手,逐渐增加定时、计数等条件,把或、与、非关系理顺;
3、进而练习整数运算、实数运算、类型转换;
4、量程转换、PID调节回路的建立及P、I、D参数的理解(最好是有个物理回路验证,比如变频器+电机+测速传感器);
5、循环、顺序、跳转等程序控制(尽量避免跳转,非跳不可时也是跳的越近越好);
6、中断、通讯、位置控制....

本人以ABB工业机器人配件DSQC系列和Motorola MVME系列,GE 卡件 模块 驱动器系列为主攻。各位电工朋友可根据自己的条件选择适合自己的PLC品牌,由于PLC的基本框架大同小异,学会一种至于其它的学习起来也就简单了。