Control.com - Nerds in Control

Hello,

Just wondering if the new enhanced Mark VI controller supports DNP 3.0. Just wondering about interfacing the Mark VIe to a RTU via DNP. I believe the old Mark 6s support Modbus, but my understanding is that Modbus does not have timestamps.

GE is not "freely" distributing the manuals for the Mark VIe, so that's a tough question to answer without access to the manuals.

If I recall correctly, DNP communications are done "through" the HMI (running CIMPLICITY and/or Proficy), and the HMI relays the data requests/data from the turbine control processor(s).

I also seem to recall that there is some version of GE CIMPLICITY's implementation of OPC that supports time-tagging of alarms, events and data, but that may just have been something that was in the works.

I don't think the Mark VIe, itself, speaks DNP 3.0. I do believe that GE has at least one option for time-stamping data from their turbine control systems, whether it's done directly with the control processor(s) or through the HMI. It's certainly probably one of the most common questions and requests and bid specifications for their equipment as people try to integrate Speedtronic turbine control systems into an over-all plant control system.

But this is one of those questions that's best asked of the manufacturer (though we all know how hard it can be to get a timely, and correct, answer from many major multi-national corporations (not just GE).

You're absolutely correct when saying Modbus does not have timestamping feature.

The Mark VI and Mark VIe don't directly support DNP (as far as I know; it certainly isn't in the manuals). Typically an OPC-DNP gateway is used (the one I've seen was from Triangle Microworks) with either Cimplicity or WorkstationST acting as the OPC client/server. I wasn't involved in configuring it, so sorry I'm not much help beyond that.

Triangle Microworks seem to have about the best DNP gateway solution for just about any application, not just GE Speedronic turbine control systems.

But I have to wonder about the whole time-tagging issue. If people think they are going to get real-time tagging of data from the Mark VI or Mark VIe, they haven't really looked at nor understand EGD and the concept of Exchange Pages and time-resolution.

I believe that alarms (process and diagnostic) and events (as defined by GE) are time-tagged, but data requests or state/value changes must 'pass through' the EGD via Exchange Pages which occur at specified intervals.

Actually, I don't think the whole concept is really documented very well anywhere by GE or GE/Fanuc. But, time-tagging of data is subject to the method/protocol constraints. And that's EGD for Mark VI and Mark VIe.

GE handles alarms and events outside EGD. They are time stamped to 1 ms, but you will not be able to "get at" them directly.

GE's WorkstationST provides interfaces to EGD and alarms and events. WorkstationST also includes both OPC DA and OPC AE servers.

You can receive Mark VIe alarms by connecting an OPC AE client to WorkstationST, which runs on every Mark VIe HMI.

And no, the Mark VIe does NOT talk DNP 3.0.

DNP 3.0 was developed by the Transmission and Distribution people. The various and sundry protocols that the Mark * controllers speak were developed for the power generation folks.

The two organizations don't talk much.

Don't we wish that they did!!!