Dear Sir,
Is Torque converter Graphic (Guide vane changing) needed in GT 7EA MVie HMI?

 

Dear Sir,

Is it needed? No.

Would it be helpful? Probably.

I've never seen a GE-design Frame 7EA heavy duty gas turbine with torque converter guide vane position feedback, so any animation would only be an indication that the turbine control system was commanding the torque converter guide vanes to move--not that they were actually moving. My personal preference for animation is it only be used when there is proof positive that some is occurring or has occurred --not that the turbine control system is commanding some action to occur. That leads to a false sense of security--in the case of the torque converter it's happened on numerous occasions that the torque adjustor drive motor motor starter breaker tripped or someone left the HOA switch (Hand-Off-Auto) in Off or Hand and even though the guide vanes were being commanded to move they weren't actually moving. Without position feedback from the actuator any animation is misleading.

 

Dear CSA,

Thank you for your valuable answer. Before I found the same graphic in GE 9E frame which having 88TM, and it's drain solenoid 20TU-1 graphic. If cool down mode start given (@ lube oil header temperature 36 DegC 88CR start and TMGV angle in open full. If TNH not increased, means we can raise TMGV manually and found Shaft speed increasing. I am thinking is same can use for 7EA also? Here they didn't provide the graphic.

 

Dear Sir,

The Belfort (France) division of GE has responsibility for GE-design Frame 9E heavy duty gas turbine and they have demonstrated a tendency to change and modify long-standing control philosophies and practices. Your use of the signal name TMGV indicates they have begun to use torque adjustor drive motor mechanisms with guide vane position feedback.In the past, limit switches were used to provide indication of torque converter guide vane position to the turbine control system and while an analog position feedback would be useful at times if the torque converter is not in the proper position to provide the torque necessary to rotate the turbine shaft then the adjustment of the torque adjustor drive motor is likely questionable, regardless of lube oil temperature.

GE-design Frame 7EA heavy duty gas turbines are the responsibility of Greenville (USA). While both turbines have the same type of torque converter, Greenville had not been using torque adjustor drive motors with position feedback devices, but may have changed to them. Can you find TMGV in Toolbox/ToolboxST, and does it change value during operation? If so, and TMGV is not used on the graphic display then it would seem an oversight on the part of the group that designs the graphic displays for Greenville.

Belfort does not coordinate with Greenville, and Greenville doesn't coordinate with Belfort. Greenville tends to follow long-stand GE heavy duty gas turbine control philosophies and practices, whereas Belfort tends to charge things even when they have been working fine for decades and don't need to be changed, and, indeed, Belfort seem to just like change for the sake of change.

If you find the torque adjustor drive mechanism on the 7EA unit you are working on to have torque converter guide vane position feedback you should work with the packager of the unit to add the value to the graphic as it would be useful.

Please write back to let us know if you find the torque converter guide vane position feedback input on the Frame 7EA unit you are working on; it would be helpful to know if Greenville has started using the input.