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MARK I Control System Backsheets
Collecting diagnostic data from Mark I system

I am trying to collect diagnostic data from Mark I system. Do you know of anywhere I can obtain MKI backsheets?

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

The MK I backsheets include detailed circuit diagrams of the SPEEDTRONIC analog control cards. They are (or at least were when I worked for GE) considered proprietary information, and as such were not available to non-GE employees. The elementary diagrams provided with the equipment showed interconnections among the control cards and their connections to the physical analog I/O and discrete logic I/O.

You did not say what kind of diagnostic data you want to collect.
The Mark I (and Mark II) SPEEDTRONIC cards do not provide self diagnostic information for the control system. They did have some alarm outputs that were connected to light-box type annunciators. The analog control signals were generally not made available for external monitoring. Some customers asked for a limited number of these, and isolator cards that provided 4-20 ma signals were provided for a not so small fee. You could not physically accommodate many of these cards in the Mark I control card racks - only 4 signals (I think) per isolator card, each card occupying 1 slot in the rack.

Back in the early 1980's GE offered a SCADA type monitoring system that included what was essentially a large A to D converter for the analog signals, the digital side of which was connected to a minicomputer (PDP 11 at first, later on VAX 750), but this was not a big seller because not many end users could justify spending the money on it. This was only used on Mark II, to my knowledge, not Mark I controls. It was called DATATRONIC, a name also used for a Mark IV vintage control system, which also had a short lifespan.
At this point, if you really need to import data from this turbine (or turbines) I suspect it would be a lot more cost effective to replace the Mark I control with a Mark VIe simplex control.

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

We had 2 Mark 1 systems and a Mark 2 AMS system. We are just replacing the last system now after 39 years of very reliable service on the Mark 1's and 32 years on the Mark 2. We hooked up our own signal isolator modules years ago to monitor critical signals continuously and available for viewing on a PI system. All valve positions, Load Set, Load Ref, EL, Speed, Speed Error, Power Supply Voltages, and Oscillator outputs were monitored with 1 second scan times. If something went wrong, usually the monitored signals would point to the problem. We also had a 16 channel high speed recorder available to monitor anything you wanted to diagnose noise problems etc.

GE provided us with the detailed schematics that showed all board mounted components. Integrated circuits were shown simplified. I thought all customers got these prints, I know that other utilities have also been provided with these documents.

It is not cost effective in this instance (client specific dynamics) to replace the existing MKI equipment. Controller replacement has already been explored. A cost effective solution is to hook up a number of analogue signals from the panel into a purpose configured data collector. The signal collection will be limited and will focus on the points where maximum interpretation will be available using proven rule based analytics and remote monitoring. I am aware that GE have passed a number of these back sheets out and that they have been recognised as public domain and are used by after market card repairers. The purpose of access to the back sheets is to define the best available point of connection for our purposes as all the available pins are not shown on the elementary. I have installed and designed MKI to MKVI and know how useful they will be in optimising connection, and although not absolutely essential will provide a good input to the final design. Any assistance would be most welcome.

> Any assistance would be most welcome.

You could trying reaching out to G.T.C.

I know they can help..!!

GE should have provided a large package of drawings for your unit. These drawings should include mechanical drawings for the turbines, generator, valves, pumps, piping, foundation, etc. On our 3 units they also included detailed drawings of the Alterrex excitation controls, and turbine control system. The drawings that GE provided were all summarized in the GE CONSTRUCTION PRINT LIST.

On our older Mark 1 units, the detailed schematics were also included in the GE instruction manual Volume 3. In other words, the manuals contained the same detailed schematics as the construction prints. Pin numbers, resistor and capacitance values were all provided.

On our slightly newer Mark 2 unit, the drawings in the manual are not detailed like on the Mark 1. But we were still provided the detailed drawings as part of the construction prints.

So I would advise you to review your construction print list and look for E drawings.

Do you have any soft copies of your MKI documents? If you have, I'd love to get a copy.