Can someone provide clarification on whether the figure of 64 Meg/s in the control specification from GE for the Frame 5P denotes 64 megawatts per second, or if it denotes another unit of measurement? This query arises following our recent upgrade of the plant control system from Mark IV to Mark VIe for both the Frame 5P and Frame 6B. We've noted that the specified ramp rate of 64 Meg/s for the Frame 5P appears impractical, while the rate of 0.05 Meg/s for the Frame 6B remains acceptable.

Recently, we came across this constant setting within the "MANSET3" control block of the Mark VIe system, and the units have been operating consistently for the past few months.

 

You can right click on the block and select 'block help' to see how the block works. Short answer is yes, Rate1 and Rate2 are in units/second. However, in the example shown, those rate limits are just for how quickly the preselect MW setpoint changes. The actual rate of change for the turbine MW will depend on the raise and lower load regulators and other factors.