This is a utility that I use to calculate how long certain devices will last when powered by a pair of deep cycle marine batteries that I have ready to use in case of a power outage.

Enter two of the three values (volts, watts, or amps) for each device in the form below and click CALCULATE. First, the values you entered will be highlighted in green and the remaining value will be calculated. Rows highlighted in red indicate that no calulation was performed. You will need to change any of the values for a recalculation to occur. Secondly, the estimated runtime for the array of devices will be calculated at the bottom.

Default values for my use of this application are in place. However, you are free to change anything to suit your needs.

1	VOLTS	WATTS	AMPS
2	VOLTS	WATTS	AMPS
3	VOLTS	WATTS	AMPS
4	VOLTS	WATTS	AMPS
5	VOLTS	WATTS	AMPS
6	VOLTS	WATTS	AMPS
CALCULATE	TOTAL WATTS	BATT VOLTAGE	BATT AMPHOURS	AMP DRAW	RUNTIME