Dear CSA,

Thanks a lot for your informative replies. We are planning an upgrade from Mark V to Mark VIe (the proposal is approved already). We just need to know some details about the upgrade. Does it include adding more instrumentation to the turbine? or changing any? We are particularly interested in Bentley Nevada vibration system. Does Mark VIe upgrade include an enhanced vibration monitoring system? Can we find a brochure/list that contains all the scope of the upgrade? Can you share a manual with me so I can start learning a bit about Mark VIe?

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Mohamedibr752,

There are Mark VIe upgrades, and there are Mark VIe upgrades.

GE loves to sell what has been variously called a "Mark Ve" and a "Mark V Life Extension (LE)" and "Mark V Migration" and several other names--but which retain the cores and plastic card carriers and ribbon cables and existing I/O terminal boards and wiring. They are very poor at communicating to the purchaser exactly what they are buying--and the technicians who have to work on the resulting system often believe they are getting a "full" Mark VIe when in fact they are getting Mark VIe-compatible cards installed in the existing Mark V cabinet.

The other Mark VIe upgrade would involve completely removing the Mark V and replacing it with a true Mark VIe, which involves a LOT of wiring modifications and interposing terminal boards (unless new interconnecting wiring was used, or there was a Marshaling Cabinet on the Mark V).

So, you should clarify what kind of Mark VIe upgrade you are actually getting. The Mark V Life Extension is touted to Customers as being less expensive and requiring less time to install and commission. But, there have been very large gaps in the HMI and configuration of such systems leading to lots of commissioning problems which lead to long delays in return to service and in reliability and availability.

Further, on these Mark V Life Extension projects usually there is little or NO loop-checking of field devices and instruments so, there are usually many problems associated with non-working field devices--or wiring--which are incorrectly attributed to the new control system, or, worse, are not discovered until some damage has occurred.

Many Customers mistakenly assume that when a new control system is installed on an existing system that the supplier will check every input and output and resolve any existing problems with the equipment and/or wiring--and that's just a ridiculous assumption. The supplier has contracted, in most cases, just to supply and commission a new control system--not to resolve any existing wiring and field device/instrumentation issues. Loop-checking and resolving issues can greatly increase the time for commissioning--and that increases costs and increases the time the unit is out of service. (Never mind that it's the PERFECT time to find and resolve any issues--known or unknown; no one wants to take the time, or incur the expense to do so.)

The Mark V Life Extension does use the newest configuration and troubleshooting tools (WorkstationST, ControlST, ToolboxST) which can make troubleshooting easier than in the past. But, without proper training and access to the software trying to learn and understand in advance is difficult, at best. You can do a World Wide Web search for GE publications related to the Mark VIe and Mark V control upgrades; I believe GE is making many of the publications readily available on the Web for download. (At this writing, I don't have the publication numbers; perhaps someone can post them to this thread if they know them.)

But, again, you should clarify exactly what upgrade you are getting before downloading any publications because you want to be sure you are getting the appropriate and applicable documents.

Finally, since GE owns Bently-Nevada it can be very easily integrated using several different methods into a Mark VIe or Mark VIe-compatible turbine control system. Just work with your salesperson/application engineer to understand the possibilities (which are many).

Hope this helps!