How does DS1's electrical system work?
The power consumption of the low voltage (28V) circuit which runs all electrical devices except the ion engine is around 450W. It takes around 16 amps (450W / 28V, given that P=IV) to run the low voltage circuit.
The nickel-hydrogen batteries on DS1 are 10 amp hour batteries. That means we get 10 amp hours / 16 amps = .625 hours (or about 37.5 minutes) of power when running from a full-charged battery and all of the low-voltage devices switched on and running at full power. Generally, the low voltage devices are running at lower powers than full power, and almost never are all of them on at the same time, so the battery life is usually longer than that. Generally, the battery life is about three hours. If the electrically-powered ion propulsion engine is turned on, it uses over 2000W of power, which vastly exceeds the battery's ability to supply power. The ion drive is not even connected to the battery.
What are batteries?
How does power get distributed in DS1?
What happens to a ship when it runs out of power?
How do batteries work?
What DS1's battery life?
What's a circuit?
What are volts and amperes?
How much power does DS1 use? How much power does it produce?