CPU BUS UNIT ERROR

[frank.raymond]

I have been having intermittened CPU faults. Up until now the maintenance team has been resetting and going about their business. Apparently the problem is happening more frequently. This morning I hooked up to the PLC that holds the "pass/fail database" for product routing purposes. This is a CJ1M-CPU13 controller with two I/O modules and a CLK21 module. During this time the CPU did fault and I recorded the following message from the error log: 0x0200 CPU BUS UNIT ERROR 0. I checked the error code in the W393-E1-07 Sysmac CJ manual. I am now monitoring the following address: A402.07 and A417. As I understnad A402.07 tell me I have a fault and A417 will tell me the CLK module's unit address. I know I can cycle power to the processor and recover from the error however I need to track this puppy down and resolve the prolem. I'm sure I will be learning a lot about CLK during this repair. Now for my questions: Can data from the other nodes be generating this error? If so, how can I determine which node is creating the problem? I went into CX Integrator and tranferred the error logs. WIll this be a tool to determine where my problem lies? Any thoughts will be appreciated. Thank you in advance. Edited January 7, 2008 by frank.raymond

[PdL]

I had a similar problem recently and I programmed some functions to store the information when the error occurs. I haven't had the chance to go on site since though. Here's the topic. Do you have datalinks running ? Automatic or manual ? You should be able to read the logs from the other CLK nodes which tell you when which node stopped participating in the data link. How many modules are hooked up in the CLK network ?

[frank.raymond]

I have 17 nodes. What I didi see this afternoon was the production line had stopped without a fault light. I went ahead cycle the PLC that had the fault earlier in the morning and the line started back up. I started doing some 'troubleshooting 101' (ie reseat modules, tighten connections, etc) What I found so far is terminating switch on the module in question was switched to on (this PLC is not at either end of the network. and the PLC next to it which is at the end of the network at it's terminating switch off. I doubt if this will cause my problem however it is a start! I have decided on the next occurrence to change the CLK21 module

[sonicjw]

I got a similar case for a CJ2M-CPU31 unit, there were " 0x0200 CPU BUS UNIT ERROR 0 " from time to time. The unit would gave all 7-segment display off after power on when the Ethernet was connected. This error also found in the EIP unit error logs "0x0601    0x8000    CPU Bus Unit error". So we swapped the EIP board with another unit, the errors gone forever.