DC 12V Step Up to 48V 6A Boost Converter 288W DC Voltage Regulator Power Converter Transformer for Golf Cart Club Car Solar System

Q: What size fuse should be used on the input side?

The input at 12v would be 24amps since the output is 288 watts at 48v. Also that raises some concern because the input wires are 16awg, which is rated to handle only about 10amps at 12v. This is not to US wiring standard and could potentially cause a fire. When I asked the seller about this they simply answered "yes, it is ok" with zero explanation as to why. But the facts are it isn't technically safe with those specs. That input wire should be at least 8-10awg if using a 30amp fuse.

Q: So will this go both ways? 12v to 48v up or 48v to 12v down?

No, it is 12v to 48v dc step up converter

Q: Will the output be regulated, that is limited to 3a, 14 watts, regardless of the load? and with no damage to the buc?

Yes, this 12v to 48v converter will automatically adjust the current and power required by the device at the output, provided that the voltage of your device is 6-16v.