Something I copied many times for my own firmware configs, but not knowing why:
The maximum current to the heated bed and nozzle is limited in the stock TAZ 5 firmware to a PWM duty cycle of 206 (bed) and 225 (nozzle) witch is 80% and 88% of the possible maximum. Does anybody knows why they limited that? Both parts are made for 24V, so there should be no risk of burning them at 100% power… 
They might burn out faster, or the drivers might over heat are a couple I can think of.