Today is...
Wednesday, April 25, 2018
Welcome to, the global online
community of automation professionals.
Featured Video...
Featured Video
Wiring and programming your servos and I/O just got a lot easier...
Our Advertisers
Help keep our servers running...
Patronize our advertisers!
Visit our Post Archive
Mark4 Diagnostic eeprom Fail
Mark4 eeprom HUMB u28, 30 failed diagnostic

We have a Frame-6B power plant with Mark4 Turbine Control that has a diagnostic that appears to be self explanatory, but wanted some confirmation or to hear if any others have had this happen.

We had to power down the Mark4 control system for upstream power system maintenance. We turned off each power supply, R-S-T-C and 2 for IO, before powering down the system. After about a week of downtime, we powered it back up, with fingers crossed as usual.

The main displays show a diagnostic alarm as follows:

Primary eeprom changed, not backed up
Diagnostic alarm see display

The diagnostic page shows this:
CC002 eeprm 1 <c> cksm fail humb2k u28, 30

I powered down C core and checked all the ribbon cables and reseated the cards. We had a spare HUMB card but no new eeproms so we swapped the eeproms onto a new card, set all the berg jumpers, just to rule that out but the same diagnostic comes in.

It looks like eeprom U28 and U30 are bad. are these the only 2 eeprom that I need to change? (all others seemed to pass the test as I saw them scroll through the start up page.)

I am unfamiliar with this system and am concerned about wiping the existing memory so it looks like we need new eeproms and someone familiar with changing them out. I read that there is a specific method for backing up the memory and replacing the eeprom without wiping all the data.

Am I overlooking anything? Can anyone comment about any similar experience? Anybody have an field service people that may be up for this? Any idea where to get eeproms?

WORLD OF CONTROLS can help you with backing up of EPROMS and supplying the same.

1 out of 1 members thought this post was helpful...

Is the unit still operational?
If not; as you have a message stating that the Backup EEPROM to Primary is incorrect why not try a restore from the backup to Primary [data Pg 07 - EPROM Maint]

Slight chance the primary might have just been corrupted, and the backup data is saved in HUMB2UK U31 to U33 which is passing your tests.

Otherwise I'd recommend the services of Gas Turbine Controls, speak to Sam Leyton <> who might offer advice and can arrange backups and replacement EPROMS

It would be great if you could keep us informed of the outcome, this is my worst nightmare, we have two MK4 units running 9E turbines and no backup and I can't convince the management how close to disaster we are running.

>Primary eeprom changed, not backed up
>Diagnostic alarm see display
>The diagnostic page shows this:
>CC002 eeprm 1 <c> cksm fail humb2k u28, 30