Circut Breaker or In-line Fuse?

[black64]

View attachment 93722View attachment 93723 I totally understand, they have been used forever with very little problems that doesn't mean that there isn't a better option. I have a lot of time and work in my engine compartment and don't to run the risk of a big black spot on my new paint. I wasn't referring to the link protecting the cars entire power source but the headlight circuit itself when I suggested a fuse "sorry for any confusion". You said there isn't a fuse big enough, this is the one I plan to use you can get them as big as 125 amp. Tell me what you think, any reason I shouldn't go this route. Here is a link to a picture of one blowing "probably an extreme case but nonetheless" oldfuelinjection.com/files/fusible-link-blow.pdf Sorry link doesn't seam to work but if you google it it will come up

There is nothing wrong with a fuse if it is large enough, the fuse you are looking at happens to be from the marine area usage. The fusible link is a pain to service but it is tried and true usage. As a rule we used 135% of amp load for a fuse under hood to allow for temp compensation. There are circuit breakers with push/pull on/off also that is used in the transit bus industry that you can use also. I do not blame you for not wanting to ruin your paint that could happen if the link was resting on the body. We place them as near the batt source as possible to have the most protection from a direct short. The breaker pic is a bussman marine available from a 50Amp to 150Amp which you could use also.

 

[shag766]

ok, electrical is not my fortay. reading all this post i would lean to proper size and placement of a breaker. if i am reading this right if there is a problem and you are on the side with no lights, what do you do. go over every thing looking and hot wire the fuse or reset the breaker. i am guessing here, but couldn't you un-plug some lights till breaker doesn't go off and get home. guessing.

 

[Bruzilla]

Well, some context might be helpful here. Unlike the factory wiring where you have 20-30 feet of wire, firewalls, hard to see fuse blocks, multiple splices and connections, and lots-O'-tape to work through, the relay upgrade eliminates all that. You have two very short power wires running to the relays, and two wires running just a few feet to the headlights, so there isn't much that can go wrong that will cause a short unless you do something really, really, stupid like make the primary wire two feet longer than it needs to be and run it against the exhaust manifold. Plus, the circuits for the low beams and high beams are completely separate, so even if one were to fail you would still have the other. The only Single Point of Failure (SPOF) in the system is where the two primary wires connect to the alternator (or battery), and if that connection fails it doesn't matter what sort of circuit protection you're using since the circuit is no longer energized.