What Size Battery Isolator Do I Need

Figurer | Sizing a 12 Volt Battery to a Load

Do y'all have a 12v device you need to ability, simply don't know what 12-volt battery you lot need? This calculator is designed to aid you find a deep bike bombardment when a continuous 12-volt load is practical.

If you know how much power your application takes to run, and the time you lot would like to run it, nosotros'll recommend a 12-volt bombardment. This figurer is designed to provide a properly sized AH (Amp Hours) rated battery without excessively discharging the battery.

Keep in mind if you lot are using an power inverter yous will get-go need to convert the AC Amps to a DC Amps before using this calculator.

Choose Your Battery

Walkthrough

Case	The first Field to enter information into is labeled "Load Size". This is typically found on the device y'all are running; for light bulbs information technology will be in watts and you lot need separate by the voltage y'all are running in-typically 12 volts. Other DC devices should be rated in amperage.(Notation* if yous are running AC devices, you will demand to figure out the DC amperage using our Air conditioning to DC calculator). For our case nosotros are running a 12 volt 15 amp swamp cooler.
Case	The second field is labeled "Load Duration", which is completely up to the user. If you want your load to run for 5 hours, put 5 every bit in our instance shown here.
Instance	The tertiary field, "Temperature Adjustment", is for adjusting the calculations for extreme temperatures. For our example, information technology is above 85 deg. F, so check the box. (Note* if you are using Gel batteries in temperatures beneath 0 deg F, and higher up -60 Deg F, there is no need to check the box.)*
Example	The 4th field is to adjust for the age of the bombardment beingness considered. Since the greatest usage of the calculator is to figure out what battery to buy, usually the box volition be left unchecked, equally in our instance, just it is at that place in case the batteries available are older.
Instance	The next three fields are for selecting what battery type you are going to use. Cull from Gel, AGM, and Flooded. For our instance we select the AGM Bombardment.
Instance	The last Field is where the calculator waves its magic wand and tells you what you need. This number is rounded to the nearest whole number, and will tell you lot what battery Amp Hour rating to look for in the selected bombardment type.
For our case, our 15 amp swamp cooler will run safely for 5 hours with a 180AH, rated at 20Hours, AGM battery. For a little more than detail on the math check out our Math Behind the Magic article.