I have a project that requires an odd voltage of 15DCV. The power pack that I plan to build will be two 12DCV 7AH SLA batteries with a DC-DC converter.
So I know that my starting conditions will be: Input Volts: 24v Input Capacity: 7AH
DC-DC converter (LM2596): 24DCV to 15DCV
Load: intermittent (6-12 times/day) 15DCV, ~1 amp, ~30sec duration
My question is "How does the DC-DC converter factor into the load calculations to figure out estimated battery life?"
How do I figure in loses from the converter?
Supplemental information: I know that running the same system at a reduced 12DCV results in about a 48hr runtime on a 12v SLA 1.3AH battery.
Thanks for the help!