Lighting t5 to hps

Hi there just asking anyone there a question on switching light systems.I currently veg under t5 4x55w lights a total of 220 watts at 10,000 lumens.Now just thinking of flowering under hps lights but can only find 250watt hps globes.Will this work? is it just a matter of changing the hours of light or will the higher watts in the hps affect the flowering & not trigger the plant into flower. :flushed: