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Our unit comprises of a single 9FA gas turbine and a single A15 steam turbine. Our shutdown time using the auto stop sequence is about 49 minutes (Auto stop initiated to GT breaker open). We are contracted to shutdown in <40 minutes therefore our customer is penalised for every shutdown. It’s my understanding the 9FA Gas Turbines unloading rate is 0.33% with respect to TNR. During the Auto shutdown when the Steam turbine breaker opens the GT is at about 80MW’s, the GT then takes about 25 minutes to unload to breaker open which is well in excess of the 0.33% unloading rate. To put it simpler the GT should be shedding about 7MW’s every minute but is instead shedding about 3.3MW’s a minute. Why is this happening? When the ST breaker opens a “ST Trip” is generated, if we “Reset” the ST the GT unloads to breaker open in a couple of minutes which is too quick. In the MKVI auto stop sequence what controls TNR when the ST breaker opens and the GT is then unloaded?