Inverter Chargers

These devices are inverters when no electricity or generator power is available and battery chargers when mains or generator power is available.

This can make sense in something like a motorhome or a house that suffers from unreliable electrical supply. It can also be a good idea if you have a high quality generator and are installing a solar system or if you are planning a solar system and need a quality battery charger for occasional use. An inverter/charger is somewhat cheaper than a quality inverter and a separate quality battery charger of the same power output. An inverter charger can also be a little complicated to the uniniated.

The combination of inverter + separate battery charger

An inverter/charger has several advantages and some disadvantages over the battery charger and separate inverter combination. First let's look at using a battery charger that is separate from an inverter:
When the power is low you start your generator and plug in the battery charger and battery charging commences. You still continue to use power from your inverter. An inverter delivers high quality power and your power supply remains quality. This can be an advantage as you will see shortly when you look at the difference. A problem only arises here if you need more power than your inverter can provide and you wish to use the generator for this power. You need separate circuits or a changeover switch to direct your generator to your power points.

Joining inverter and charger together into one box ...

When you use an inverter/charger all the above stuff about separate devices is redundant. You are using inverter power through your power outlets when the device is an inverter. You are using generator power through your power outlets when your device is a battery charger.

The process of going from inverter power to generator power at your power points is automatic and this function is provided by the inverter automatically with a built in automatic transfer relay. It is so simple that most electricians scratch and mumble and fail to grasp the basics without explanation! The swap between inverter power and generator power is virtually instantaneous.

Check it out so you can explain it if need be!

• Your inverter/charger has three connection points: Battery, household supply (output) and generator (input)
  
• When you use your inverter charger as an inverter, power comes from the battery, gets "inverted" to household power then comes out the household supply line. Nothing different from a conventional inverter here.
• When you start your generator or plug in the mains an automatic transfer takes place via an inbuilt transfer relay. Transfer is virtually instantaneous! Voila! your inverter is no longer an inverter. It has become a device that is now passing gnerator power through to your house and the components inside that were once operating as inverter components are now operating as battery charger components.

An inverter charger does the above process automatically and is provided will all components to be three devices in one. The first two are inverter and battery charger and the third is the automatic transfer part that seamlessly transfers power between inverter and generator. A quality inverter charger will also have a delay so a generator can warm up and stabilise before being connected.

There is a few advantages and a few disadvantages associated with this automation

The obvious advantage is that everything is in one box and the purchase price may have been less than a separate inverter and separate battery charger of the same quality. If you use heavy power tools or welders or such stuff you need not worry about plugging them into separate power points or switching over your generator via a switch. All this is done for you. Your inverter/charger could have an board electronics to automate starting the generator (if your generator is suited to auto-start) and will be a highly reliable and space saving device. A good inverter/charger will have electronic sensing to determine generator load and will reduce battery charger output if your household demand on the generator is high.

The disadvantage is this: If you use anything but a high quality generator your power quality will suffer. The output from the average generator is way inferior to that of a modern sine wave inverter. Whether you want to or not, if you are battery charging with the charger part of your inverter/charger you are also using generator power from your generator in your house.

Some other uses for inverter/chargers:

The use of an inverter/charger is not limited to solar power systems that need a generator. These devices are pretty neat! For example if you only have a generator for your power and nothing else, adding one of these devices plus a battery bank will give you 24 hour power for a vastly reduced generator run time. the savings in fuel alone could well pay for the installation cost.

If you have mains power connected and it is unreliable or you need a guaranteed continuous supply for medical equipment or computer systems an inverter/charger will provide all of this automatically and reliably.

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