Bulb Ramping Help

[DJHaze596]

I've been trying to Capture the Sunrise in my Complex,  and the Sun comes up right above the Complex Fountain.  So my goal is to Capture some Night Footage Timelapse then the Sunrise.  The Night shots came out great but when i did the Sunrise,  It started out nice but than i had to stop it because it got Washed out.  It kept over exposing.  and the sun wasn't even peaking yet.  So messing with that kinda messed up the Timelapse on playback.  There's no tutorial for this Feature so idk if i'm doing it right.   I set it to Sunrise and Rampspeed was set to 0.50 the first time,  than 0.100 the second after the mess up.  My settings went from 5 Second Night exposure to
1-3 Second Sunrise Exposures.   I Mean everything worked,  ISO,  Aperture,  and Shutter Changed,  but i just don't understand why it overexposed.  My other mistake was only doing 100 Shots at a time because i didn't want it to Overexpose,  But it did after about 300 Shots.  Any Tips?