With certain chargers, they have the ability to use a 12V source. Some chargers require a 12V 1A source, and others, a 12V 2A source.
Am I correct in saying that, in order to provide the correct power to the charger, when using a charger that requires 1A that the fuse inside the car charger has to be 1A? Same goes when using a charger that requires a 2A source?
Well… It would need to be @ minimum of the 1 or 2 amps.
Amps are asked for and not given, if that makes any sense - you could use a 100 amp fuse and the charger will still only pull the 1 amp.
But at 100amps it would be less of a ‘fuse’ in a 2 amp situation and a tad more a ‘nail’.
A fuse is designed to break the circuit during a fault. It does not regulate amps, except in that it can not supply more than its rated for, within specs that is. ie: a 5 amp fuse can supply any number of amps, upto 5. If the demand exceeds that 5, it will pop the fuse.
Use the right fuse for the vehicle in that fuse slot (assuming its a cig lighter etc) as it likely will be fusing more than a charger over time. So long as you dont exceed the amps of the fuse, then it should function as normal (absent a short). Its when there is a short that the fuse becomes important, which is why you dont want to exceed the recommended amperage fuse. However if it is a cig lighter socket and its fused at say 10 amps in the cars fusebox, and you worry about the margin being too much for safety, you could put a fuse in the line you plug into the cig lighter socket to the device that was lower than the 10 amps, say 5. The lighter socket could still deliver 10 amps, but the device would be protected at anything over 5 draw.
In your scenario, the 1 amp fuse would not work well with the 2 amp device (depending how accurate the fuse rating was and the draw of the device but assuming 1 amp is exactly that, and 2 amps is the draw), but the 2 amp fuse would be fine with the 1 amp device. It would take some peculiar circumstances for the 2 amp fuse to be too hot for the 1 amp device and not blow the fuse if there was a fault.
Thanks for the replies.
I’ll have to look at my car’s manual to see what’s in the fusebox of the cigarette lighter socket.
I already have a car charger that has a 3A fuse in it, but I’ll consider getting 2A fuses instead. This is to power up either an Xtar SP2 or Nitecore D4 charger I have.
It’s probably a 10A fuse.
Fuses are specced at a level higher than the expected load. They are there for safety and equipment protection when things go badly out of spec. In the case of a car charger, the fuse should, at the very least, have a lower rating than the cord, because you’d rather the fuse blow than than have the cord melt or catch fire. I have no idea what a standard safety margin would be, though.
Oh, also, its worth asking, these car chargers, is the current specced you are looking at specced at output voltage, or input voltage?
Input voltage. Xtar SP2 is 12V at 2A, whilst the Nitecore D4 is 12V at 1A.
edit: checked the manual, it says it’s either a 7.5A or 15A fuse. Either way, I think the original plan of using 2A fuses in the car charger is fine.