How Do I Charge a 24V From a 12V Alternator?by Darby Stevenson
While most vehicles use a 12 volt (12v) electrical system, many buses (and some boats) utilize a 24 volt system. Some 24v systems actually employ a series of linked 12v or 8v batteries. The 24v systems that employ 12v batteries can be recharged with a 12v alternator by simply being plugged in like any other 12v battery. If the 24v system uses an actual 24 volt battery, the electricity will have to pass through a voltage converter before it goes from the 12 volt alternator to the battery.
Purchase a 12v to 24v converter. If the system is going to be installed inside the vehicle, get one that is designed to be used in a moving vehicle so that it can withstand bumps and other movements on the road. Some of these converters will have different input and output options (8v, 12v, 24v, etc), so purchase one that specifically accepts 12v as input and will output to 24v.
Unscrew the screws on the terminal block of the converter, this is the point where the input and output wires connect to the converter. If the converter has more than one input and output, unscrew only those denoting 12v input and 24v output.
Connect the output of the converter to the 24v battery with standard terminal wire. The inverter end should be wrapped around the bolt at the output, then secured by re-tightening the screw. The battery end should employ a standard 24v battery connector.
Connect the input of the converter to the 12v alternator. The alternator end of the cable should use a standard alternator connection. The converter end should be wrapped around the 12v input bolt, and screwed into place.
Check to see if the converter has switches for different types of electrical conversions. If it does, set the switches to 12v DC input, and 24v DC output.
Turn on the engine to begin charging the battery.
- Talk to the experts online or in the store where you purchase your converter to make sure you get the model best suited to your needs.
- Do not touch the battery, converter, alternator, or cables while the engine is running.
Items you will need
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