DC to AC Power Inverters
DC to AC Power Inverters are devices that use direct current power from a 12 volt or 24 volt battery and convert the voltage into 120 volt standard alternating current. You can then plug all types electronics in your inverter. I would like to review all the types of electronics that can operate with a power inverter, different types of batteries you can use and ways to recharge your battery bank. The many different possibilities make this type of system extremely useful.
Lets first go into the system setup, the essential components of the system is the right dc to ac power inverter, the right type of batteries and the right charging methods. The start with the charging method and run through the system until we get to the output of the power inverters. With recently refined technology in the field of solar power and wind power harnessing device these two methods have become the standard in off gird power system resources. By connecting a wind generator or solar panel system to your power bank you can use clean reusable energy to keep to flushed with power. Researching your geographical areas strengths will be essential in figuring out if solar panels or wind turbines will work for you. There are still some areas that these options will only be able to be used as a partial charging methods, you might also need to combine both methods within the same system . Other methods of recharging still exist, you can use utility power when available to recharge your battery bank with a standard battery charger. Other off grid methods would include a using a generator or the alternator from a vehicle. If you choose to use a generator or vehicle alternator you would be using gasoline to run your charging method, so you might want to make sure you use the most cost efficient method. Now as far as the DC batteries go there is automotive batteries and deep cycle batteries. The main difference between the two types of batteries is that deep cycle batteries can be drawn down to a lower voltage and still be recharged. If a standard automotive battery is drawn down below a certain voltage the battery will be damaged and unusable. Most dc to ac power inverters include low voltage shutdowns and protect against drawing the batteries down so therefore more expensive deep cycle batteries might not be completely necessary. What you will want to look at when selecting your batteries is the amp/hrs level, the higher the rating the longer you will have power in between charges. You will find deep cycle batteries although more expensive have higher levels, and if you are using a gasoline based charging method the less frequently required recharging batteries might be the ideal choice.
Now that we covered recharging and selecting batteries we can discuss the actually dc to ac power inverter types. Most commonly power inverters are available in two voltage inputs 12 volt and 24 volt. If you are using you dc to ac power inverter with a vehicle battery source you will want to make sure it matches voltage levels. If you are setting up a free standing battery bank then both options will be possible. By wiring you batteries in parallel or series the correct voltage system can be made(please see the image below for examples).
Parallel battery connections are very simple you just connect positive to positive terminals to retain the same voltage within the entire system. If you use a series connection the batteries will use positive to negative connections and increase voltage level by the added voltage of the batteries. Once determining which voltage system you will use, now you need to look at the size of inverter. All dc to ac power inverters are listed in watts, most electronics might be listed in amps. To figure out your wattage requirements multiply your amps by standard ac voltage levels of 115 volts. One of the most overlooked aspects about calculating the wattage requirements is surge and start up wattages. When selecting the dc to ac power inverter make sure the listed continuous can handle the peak of all the surge and start up wattage levels. If you do not have an inverter that can handle your requirements you will encounter constant emergency shutdown and your system will be very ineffective. Another important aspect to consider is the differences between pure or true sine waves and modified sine wave inverters. For the difference please check our previous posts.