We use fuse taps because it is the easiest source of power and provides a reasonable clean install. Running a power line through the firewall on a modern car is a major task on its own.. and.. there is no nice way to attach a light gauge wire to the battery.Why do you think almost everyone is using fuse taps rather than direct to the battery, are we all in danger of being incinerated?
Think about it this way.. Suppose you used a tap on a 3o amp circuit to ADD another 30 amp service. One way would work and the other way would see 60 amps go through the original circuit and fail. In the image (above) the left hand side circuit "could" see a 35 amp load across the 30 amp fuse. The right hand picture will not see a combined load.
the left hand sides shows a setup where a load of 30 amps out to the original load and a 5 amp additional load will pass 35 amps through the 30 amp fuse.
it would still work but if you put it in the wrong way the second outlet won't be protected by the fuse, original outlet works either way
That is true, it also has no bearing on the protection of the original load, the issue is the protection of the supply....But it has no bearing on the protection of the camera...
Great point. I'm sold on doing it the safer way.one way you can not overload the supply wire
If you start off with a 5 amp fuse supplying a 5 amp load and you add a fuse tap with another 5 amp fuse and a camera that consumes 5 amps then if you connect the fuse tap one way around you can draw 10 amps total
I am suggesting that you should put the fuse tap the correct way around for the fuses to be in series and thus have everything correctly protected, but if you put it the other way around then the fuses will not be in series and the source will not be protected.Nigel, that is all wrong, as I stated before putting fuses in series does not double the value, you can not draw 10 amps.
If you use the fuse tap taking power for the camera from the side supplied by the original fuse you will just be "preloading "that fuse.
Let's say we use what was originally a 30 amp fuse location that supplies the rear window defroster. Lets say that the window defroster uses 25 amps when 'on", now we add an additional 5 amps to the camera. Theoretically that would blow the original fuse, protecting everything, the rear window defroster, the camera and the supply wires.
Either way you use the tap you have no danger in melting anything. The only problem is possibly now not being able to supply the original load ( the rear window defroster) with enough current.
Great point. I'm sold on doing it the safer way.
Thank you, all of this was very confusing to a non-technical person. Thank you as well @CDNinHHthe original circuit is protected regardless of which way the tap is installed