To step down from 240V AC to 12V DC for a unit drawing 80W, you will need to use a transformer and a rectifier circuit.
Here's what you need to do:
- Choose a transformer with a voltage rating of at least 240V AC and a secondary winding that outputs 12V AC.
- Connect the primary winding of the transformer to the 240V AC power source.
- Connect the secondary winding of the transformer to a rectifier circuit, which will convert the AC voltage to DC.
- Connect the output of the rectifier circuit to your unit drawing 80W at 12V DC.
Note: It's important to choose a transformer and rectifier with an IP55 rating, as it will be used for external use.
The tools you will need are:
- Soldering iron and solder
Pros:
- You can choose a transformer that fits your specific power requirements.
- A custom circuit allows you to optimize the conversion efficiency.
Cons:
- Building the circuit yourself can be time-consuming and requires a certain level of technical knowledge.
- If the circuit is not assembled properly, it can result in a dangerous situation.
You can look for off-the-shelf AC to DC converters or power supplies with the right voltage and current rating, but if you don't find one with an IP55 rating, you may need to build a custom circuit.
To give a more accurate answer, I would need additional information such as the distance between the power source and the unit, and the ambient temperature range of the environment the unit will be used in.