How long will my UPS last for?
Need any idea how long your UPS will last for? Eg How much runtime will you get out of your UPS? Then this UPS Runtime Calculator is just what you need.
You’ll need to know how much power (in Watts) your UPS is delivering. Then you’ll need to know how many battery blocks and of what Ampere Hour capacity are in your UPS.
This calculator is based upon 12V blocks only and will only accept integer values. So, if you have one single 6V battery of 12Ah capacity, then you’ll need to say it’s a 12V 6Ah battery. If the spec of your battery is not in Ampere Hours but Watt Hours, then as a very rough guide divide the Wh rating by 4 to get the Ah. If you have 7.2Ah or 8.5Ah then if you round down this will give you a minimum, and round up will give you a maximum.
Note, the calculator is approximate. There are no assumptions made on standby current consumption and inverter efficiency. These will be different for different UPS and also different at different load levels. Please just use as a guide. For example if you have an AC load of 1000W, the calculator makes no allowance for DC to AC conversion losses. This allows you to add your own. For example if your system uses 5W in standby, and has an efficiency of 90% then for a 1000W AC load, use 1000 / 0.9 + 5 = 1116W.
If your load varies over time, you’ll need to estimate the average power consumption. You’ll need to size a UPS to meet the maximum power draw expected, but calculate the runtime based upon the average power consumption.
UPS Runtime Calculator
If you want to select a UPS to meet load and runtime calculators please use the UPS Selection Tool.
If you’ve used the UPS Runtime Calculator please leave a comment or drop us a line with any ideas.