Honeywell TPS LCN电缆故障处理 点击：1673 | 回复：15
发表于：2008-02-13 15:50:00
楼主
在新年前，我公司的LCN电缆A缆出现故障，B缆正常，怎么也无法切换到A缆工作，噪音主要出现在LCN网络的最后两个节点，NIM节点和APP节点，而且NIM还被拖跨，显示“fault”，现把处理过程列出来：
1、初步判断是APP节点到NIM节点LCN电缆故障，于是把APP节点停止，电脑断电，这是LCN电缆A缆可以正常工作，但是当重新启动APP节点后，过了一段时间，A缆依旧故障；这样通过停用APP节点可以切换到A缆试验两次，都可以；
2、后来又出现问题后，停用APP节点还是无法切换到A缆；于是更换APP节点的MAU，可以正常切换，但是过了一段时间后，A缆依旧故障；
3、于是检查APP节点到NIM的A缆；从外观上看没有问题；由于无备件，新年到了，于是甩开APP节点，把A缆的终端电阻接到NIM一头；这是工作正常；春节过后，在这长达8天的时间A缆都是工作正常的；说明问题出现在APP节点到NIM节点之间，故障点判断正确；
4、目前还要两个点需要判断，一个是MAU到APP的LCNP电缆是否正常？一个是LCN A缆（APP到NIM）电缆是否正常,是否电缆受到了干扰；
5、于是重新把APP节点并入LCN网，但是这节电缆是敷设在防静电地板上的，这样做的原因是判断是否有别的电缆对它造成干扰，今天做了这个工作，目前正常，但是还要观察；
6、后续工作主要是，如果还有问题，那么更换LCN电缆或更换MAU到LCNP电缆；
7、关于后期的处理还要观察，目前只做到了这一步，毕竟备件很少，只能这么试。
我说这些，主要是认为在DCS检修和故障判断时，由于备件很少，查找问题和排除问题的方法很重要，在检修时的安全性很重要，毕竟在DCS问题处理时都是在线做的，生产在进行，必须保证安全，尤其在查找网络故障时。
1、初步判断是APP节点到NIM节点LCN电缆故障，于是把APP节点停止，电脑断电，这是LCN电缆A缆可以正常工作，但是当重新启动APP节点后，过了一段时间，A缆依旧故障；这样通过停用APP节点可以切换到A缆试验两次，都可以；
2、后来又出现问题后，停用APP节点还是无法切换到A缆；于是更换APP节点的MAU，可以正常切换，但是过了一段时间后，A缆依旧故障；
3、于是检查APP节点到NIM的A缆；从外观上看没有问题；由于无备件，新年到了，于是甩开APP节点，把A缆的终端电阻接到NIM一头；这是工作正常；春节过后，在这长达8天的时间A缆都是工作正常的；说明问题出现在APP节点到NIM节点之间，故障点判断正确；
4、目前还要两个点需要判断，一个是MAU到APP的LCNP电缆是否正常？一个是LCN A缆（APP到NIM）电缆是否正常,是否电缆受到了干扰；
5、于是重新把APP节点并入LCN网，但是这节电缆是敷设在防静电地板上的，这样做的原因是判断是否有别的电缆对它造成干扰，今天做了这个工作，目前正常，但是还要观察；
6、后续工作主要是，如果还有问题，那么更换LCN电缆或更换MAU到LCNP电缆；
7、关于后期的处理还要观察，目前只做到了这一步，毕竟备件很少，只能这么试。
我说这些，主要是认为在DCS检修和故障判断时，由于备件很少，查找问题和排除问题的方法很重要，在检修时的安全性很重要，毕竟在DCS问题处理时都是在线做的，生产在进行，必须保证安全，尤其在查找网络故障时。
发表于：2008-03-05 00:31:00
4楼
在处理过程中的学到的一个知识：
我们是在APP节点没有SHUTDOWN的情况下，把LCN A缆恢复，但是当硬件恢复完后，LCN B无法切换到A缆，采取的方法是把APP节点SHUTDOWN后，再启动就可以切换了。
我们分析了一下原因：认为这是正常的，因为在B缆正常时，DCS可以监测到所有LCN上的设备，那么在我们恢复A缆时，在A缆上就断成了两个环（两个网络），DCS认为A缆有问题，处理的办法就是把这两个网络环的其中一个环上的设备全部SHUTDOWN，并入另一个环，让这两个网络环成为一个整体，其实这些在手册上都有，不过很少碰到，
所以在处理网络断为两段时，在并为一个环时，要注意NIM千万别SHUTDOWN ，也就是把不重要的设备并入到有NIM的网络环中。
我们是在APP节点没有SHUTDOWN的情况下，把LCN A缆恢复，但是当硬件恢复完后，LCN B无法切换到A缆，采取的方法是把APP节点SHUTDOWN后，再启动就可以切换了。
我们分析了一下原因：认为这是正常的，因为在B缆正常时，DCS可以监测到所有LCN上的设备，那么在我们恢复A缆时，在A缆上就断成了两个环（两个网络），DCS认为A缆有问题，处理的办法就是把这两个网络环的其中一个环上的设备全部SHUTDOWN，并入另一个环，让这两个网络环成为一个整体，其实这些在手册上都有，不过很少碰到，
所以在处理网络断为两段时，在并为一个环时，要注意NIM千万别SHUTDOWN ，也就是把不重要的设备并入到有NIM的网络环中。
发表于：2008-03-14 22:58:00
11楼
感谢 瘸猫 的说明，他说的是对的。
只有UCN网络才有噪声的概念，好像噪声数达到6万左右的时候，会出现问题，所以我们要定期检查噪声数，定期清零；
而LCN网络显示的是每1000个信息出现的传输错误数。
但是我不赞同 瘸猫 的：当A/B缆同时出现"挂起"故障时（真正的故障），NIM为了保证冗余，会FAIL掉BACKUP节点。
因为如果LCN网络的两根电缆都出现问题，那么GUS就无法读取到HPM控制器的数据，那么在GUS流称图上就无法显示现场数据，这种情况我碰到过，在HPM通讯负荷过重时，会出现那个控制器的数据无法在GUS上显示，这非常危险，操作人员无法看到现场的数据，整个一个瞎子摸象，很吓人。
在处理LCN网络时，当时有一根电缆是好的，在GUS上状态也是显示好的，在NIM出现问题后，我立即“shutdown”了这个NIM。重新启动后NIM正常。
Honeywell的工程师给我的解释也和你说的一样，但是我不敢苟同。
只有UCN网络才有噪声的概念，好像噪声数达到6万左右的时候，会出现问题，所以我们要定期检查噪声数，定期清零；
而LCN网络显示的是每1000个信息出现的传输错误数。
但是我不赞同 瘸猫 的：当A/B缆同时出现"挂起"故障时（真正的故障），NIM为了保证冗余，会FAIL掉BACKUP节点。
因为如果LCN网络的两根电缆都出现问题，那么GUS就无法读取到HPM控制器的数据，那么在GUS流称图上就无法显示现场数据，这种情况我碰到过，在HPM通讯负荷过重时，会出现那个控制器的数据无法在GUS上显示，这非常危险，操作人员无法看到现场的数据，整个一个瞎子摸象，很吓人。
在处理LCN网络时，当时有一根电缆是好的，在GUS上状态也是显示好的，在NIM出现问题后，我立即“shutdown”了这个NIM。重新启动后NIM正常。
Honeywell的工程师给我的解释也和你说的一样，但是我不敢苟同。
发表于：2008-03-19 19:11:00
13楼
5.3 Double Cable Fault Handling Procedures
Introduction
The UCN provides correct communications in the presence of faults oone trunk or drop cable because all nodes move to the backup cable. If all nodes do not correctly move to the backup cable, some nodes will be
n
unable to communicate.
communicate over the UCN, causing loss-of-view, loss of AM control
fa
o
Faults on both Cable A and Cable B of the UCN are known as double faults. Double faults will cause one or more nodes to be unable to
and/or loss of peer-to-peer control. Dual faults to any one node’s drop
cables will cause it to be unable to communicate over the UCN. Trunk ults are likely to affect all nodes to some extent depending the location f the physical problem.
Fault Indications
S
• her nodes as OFFNET, or
itself
e
d fault in a backup drop or trunk cable and a node is
hutdown, or is powered off, or fails over, one or more nodes may be
In either case, failovers in redundant nodes may occur. On the UCN TATUS DISPLAY, the NIM may show itself as OK and most ot
• if it cannot communicate with at least one other node it will showas COMMFAIL, and all other nodes as UNKNOWN.
At least one special single-fault case looks like a double fault: when theris an undetecte
s
unable to communicate.
Recovery Approach A double cable fault situation must be reduced to a single fault situation
before communications can begin to be restored—one of the cables (A or
B) must be restored completely. Start by repairing the cable in use by
the NIM, and then repair the other cable. In some cases, full view may
not be restored even after one cable is completely restored.
NIMs Dual drop faults to a primary NIM will only cause that NIM to failover.
Dual drop faults to a secondary NIM will not cause that NIM to fail.
Dual trunk faults will generally cause NIM failover. Do not reload the
failed partner until after the cable faults are repaired. If necessary,
Release 430 NIMs will disconnect from the UCN and periodically
attempt to reconnect. This attempt can be observed at the LEDs on the
PNI or EPNI board edge in the NIM module. The self-test Led will cycle
for each attempt. In addition, the Pass Module Test LED (green) will
cycle each half second.
Continued on next page
06/05 UCN Guidelines 45
5.3 Double Cable Fault Handling Procedures, Continued
PMMs Dual drop faults to a primary PMM (or non-NIM) will only cause that
PMM to failover. Dual drop faults to a secondary PMM (or non-NIM)
will cause that PMM to fail. Dual trunk faults may cause PMM failover.
The node pair will end up in one of the states in the following table, each
of which requires a specific action. Local control and IOLINK operation
are maintained through loss of UCN communications except in the rare
FAILED/FAILED case.
The PMM SHUTDOWN command is used to recover from most cases of
loss of view, which are evidenced by an error code of 0A2x in the
COMM loss of view (where the node state is FAIL), which are evidenced
by an error code of 0A2x in the COMM ERROR BLOCK (PMM
DETAILED STATUS, MAINT INFO). This command is accessed from
the UCN STATUS DISPLAY, MODULE COMMANDS, and
SHUTDOWN. Issue the command only once.
我也没有办法，它就是这么说的。。。。嘿嘿
Introduction
The UCN provides correct communications in the presence of faults oone trunk or drop cable because all nodes move to the backup cable. If all nodes do not correctly move to the backup cable, some nodes will be
n
unable to communicate.
communicate over the UCN, causing loss-of-view, loss of AM control
fa
o
Faults on both Cable A and Cable B of the UCN are known as double faults. Double faults will cause one or more nodes to be unable to
and/or loss of peer-to-peer control. Dual faults to any one node’s drop
cables will cause it to be unable to communicate over the UCN. Trunk ults are likely to affect all nodes to some extent depending the location f the physical problem.
Fault Indications
S
• her nodes as OFFNET, or
itself
e
d fault in a backup drop or trunk cable and a node is
hutdown, or is powered off, or fails over, one or more nodes may be
In either case, failovers in redundant nodes may occur. On the UCN TATUS DISPLAY, the NIM may show itself as OK and most ot
• if it cannot communicate with at least one other node it will showas COMMFAIL, and all other nodes as UNKNOWN.
At least one special single-fault case looks like a double fault: when theris an undetecte
s
unable to communicate.
Recovery Approach A double cable fault situation must be reduced to a single fault situation
before communications can begin to be restored—one of the cables (A or
B) must be restored completely. Start by repairing the cable in use by
the NIM, and then repair the other cable. In some cases, full view may
not be restored even after one cable is completely restored.
NIMs Dual drop faults to a primary NIM will only cause that NIM to failover.
Dual drop faults to a secondary NIM will not cause that NIM to fail.
Dual trunk faults will generally cause NIM failover. Do not reload the
failed partner until after the cable faults are repaired. If necessary,
Release 430 NIMs will disconnect from the UCN and periodically
attempt to reconnect. This attempt can be observed at the LEDs on the
PNI or EPNI board edge in the NIM module. The self-test Led will cycle
for each attempt. In addition, the Pass Module Test LED (green) will
cycle each half second.
Continued on next page
06/05 UCN Guidelines 45
5.3 Double Cable Fault Handling Procedures, Continued
PMMs Dual drop faults to a primary PMM (or non-NIM) will only cause that
PMM to failover. Dual drop faults to a secondary PMM (or non-NIM)
will cause that PMM to fail. Dual trunk faults may cause PMM failover.
The node pair will end up in one of the states in the following table, each
of which requires a specific action. Local control and IOLINK operation
are maintained through loss of UCN communications except in the rare
FAILED/FAILED case.
The PMM SHUTDOWN command is used to recover from most cases of
loss of view, which are evidenced by an error code of 0A2x in the
COMM loss of view (where the node state is FAIL), which are evidenced
by an error code of 0A2x in the COMM ERROR BLOCK (PMM
DETAILED STATUS, MAINT INFO). This command is accessed from
the UCN STATUS DISPLAY, MODULE COMMANDS, and
SHUTDOWN. Issue the command only once.
我也没有办法，它就是这么说的。。。。嘿嘿
热门招聘
相关主题
- PCB原件封装方法
[2220] - 伺服脉冲当量的定义计算法[1369]
- （已结束）电源电器擂台第五十...[1562]
- 求SE-20071A变频器说明书[1584]
- 一份“不正经“的低压电工作业...[1094]
- 变频器与软启动的区别.doc[1998]
- 交直流继电器是按触点回路来...[5834]
- (已结束)电源电器擂台第四十...[4631]
- 施耐德低压产品常见问题[1215]
- 变频和工频的区别[890]
官方公众号
智造工程师
-
客服
-
小程序
-
公众号
工控网智造工程师好文精选
