s5-135u plc cann't enter run state!

[jack 0]

s5-13u plc system configuration are as follows: 1. 6es5923-3ua11 2. 6es5928-3ua12 3. 6es5922-3ua11 4. 6av1242-0AB10 5. 6es5525-3ua11 6. some digital and analog modules Now I came into a big problem that both 928A and 922 cpu couldn't enter run state, stop LED flash slowly and alternately, BASP LED light up after switching on the power supply or Overall Reset. I don't know where is the fault ,hardware or software or others? pls give some help and suggestion ,thanks! otherwise, I have also caputured the detailed ISTACK information as the attached . your response is highly appreciated! ISTACK_infomation_about_s5_13u_plc.txt Edited 22 Jul 2008 by jack

[Moggie 17]

Corr.pdf Is this an existing project or a "fresh" one? Is DB1 and/or DX0 loaded? Put both CPU's to stop mode Put the 923 into stop mode. Put both CPU's to run position then put 923 back to run position. Please see attachment for more details

[jack 0]

Thank you , Moggie! This is an existing project and can operate normally before two years . but due to some other reasons, the produce line including the S5-135u plc system stopped , Now we want to use it , powered the s5-135u plc on several days ago , found this fault . I did it according to your suggestion, but the fault is still the same. Red stop LED on 922 cpu flash slowly, and Red stop LED on 928A cpu is continuously lit . I think user program is no problem , because the two cpus 928A and 922 are with corresponding EPROM , I have uploaded their program from plc and check it is complete ,including DB1 block . I don't know if load DB1 seperate from other blocks? Edited 23 Jul 2008 by jack

[Moggie 17]

There is an error with DB1 Please overall reset your plc then load DB1 then load all remaining DB's Then carry out restart procedure above. I am attaching the pages concerning the DB1 error from the S5 135 manual DB1_FE.pdf

[jack 0]

our cpu928A and cpu922 are with EPROM , without RAM . so could not load DB1 and other DB blocks like what you said. but I connected to cpu928 and cpu922 online with PC , saw DB1 is exsit in the cpus and is correct . I think if some hardware module is fault ,but I don't know how to diagnose them? in additon, I have also a question that cpu istack info doesn't change even if remove a certain digital module from the rack. Is this normal? if don't power the digital modules supply with external 24vdc, the crossponding cpu can enter run?

[Moggie 17]

InputCard.pdf The iStack indicates a problem with DB1 in the 922 cpu. Has any extra input/output modules been added to the system? Are all the addresses of the I/O cards the same as that entered in DB1? It is possible to disable the "enable" circuit of I/O cards so that the cpu does not look for "power" on the enable inputs on the cards; please see attachment for location of "jumper" Edited 24 Jul 2008 by Moggie

[jack 0]

moggie There are not any extra input/output modules added to the system , I have also captured two pieces of DB1 I/O assignment in cpu928 and cpu922 , plc see the attached file . the digital modules located in the system are as follows : slot no. module name address 67 430-4ua12 0 75 430-4ua12 4 83 430-4ua12 8 91 451-4ua12 0 99 451-4ua12 4 107 451-4ua12 8 in my opinion, the setting of all the I/O addresses is right . Due to some reason, I didn't apply the external DC voltage to all the input/output modules .if this is a possible reason, I have a confusion that istack doesn't show DB1 error in cpu 928, but show DB1 error in cpu 922. because all the digital input/output modules were not supplied the power in this system, and DB1 in cpu928 contains all the I/O assignment in this system., DB1 in cpu922 only contains part of it . Edited 26 Jul 2008 by jack

[jack 0]

Moggie, thanks a lot for your help ! Now our problem has been solved, the cause is in missing the I/O modules's enable voltage. Best regrads jack