This may work for you, but it certainly is not that necessary to complete this amount of warmup sets.
2-3 sets at lower weights, not taken near fatigue--ie 135x8..225x5..go into workout.
For warmup, 5-15 cardio, then 5 min various light shoulder work. Just light front,side,rear lateral lifts works for me. Sometimes I like to do overhead squats with the bar just to get the body going. But back to the original, I don't feel like you have to make 20 or more warmup lifts for CNS or any other purpose.