I see you're running 480s so:
The best draw I could find for the dap1 = 1000mAh
draw for the 480s = 4mAh/pair
6 volts x 1 amp = 6watts
48 volts (phantom) x .004amp = .192 watts
6.192 watts / 6 volts = 1.032 amps
This is probably closer to 1.5 amps considering conversion efficiency.
The short version........you need 1.5 Amps per hour via 6 volts to run the p1/480 combo.