What is the main difference between MS & PG series gas turbines & what are the abbreviations?

 

MS = Model Series. E.g., 5001 for frame 5, single shaft; 5002 for frame 5, 2 shaft. Can be followed by letters to show "revision" level. Usually, higher letters mean later revision, and more power output. Main exception to this was the 5001P and 5001R. The P was an upgrade to the N which itself was an upgrade to the M. The N had a better compressor section with variable IGV's. The P had some changes in the turbine section and was Mark II control (N was Mark I). The R was basically an M with Mark II control and turbine changes similar to the P.

PG = Power Generator and is MS with the two zeros replaced by numbers that indicate approximate horsepower of the turbine. So a PG5341P would be a MS5001P rated at about 34000 horsepower or about 25 MW.