Complex sentence: While possessing a fairly high horsepower rating (2950 total HP), the traction horsepower was rated at 2800 while 150 HP was used to run the onboard appliances.
Split into simpler sentences: While possessing a fairly high horsepower rating (2950 total HP). The traction horsepower was rated at 2800 while 150 HP was used to run the onboard appliances.