Fuse blowing

[sdp.fordbarn]

When i first got my Model A a year and a half ago, I was going nuts with "blown" fuses. Probably a dozen of them. Discovered that the fuses were junk. Two different batches of them. With the fuse holder mounted on the starter, the fuse would get hot enough that the metal end cap would detach from the fusable element and open the circuit. Fuse would visually look fine but have no continuity. In most cases, the metal cap would fall right off the glass. I ultimately mounted a 30A breaker under the dash eliminating the ugly fuse holder and restoring the under-hood wiring to factory appearance. The breaker has never popped once.

 

[Benson]

There are different types of breakers:

1. The type 1 which must be manually reset after it trips.

2. The type 2 which resets by its self automatically after it cools down.

Type # 1 is much safer and less likely to start a fire.

With type #2 if a short happens when nobody is around (at night or when buying ice cream) the breaker will reset itself repeatedly as long as short remains.

Finally breaker will overheat and fail.

1. If you are lucky it will fail as an open circuit and there will be no fire.

2. Breaker can also fail in a shorted condition which may start a fire.

The IBM machines (punch card machines through System 3090 main frame) that I worked on for 30 years ALL had the manual reset breakers or fuses to prevent a fire from being started.

I never saw an auto-reset breaker ... never.

Fire is the reason why they were never used.

Many of the older punch card machines had hundreds of manual reset breakers or fuses.

 

[rotorwrench]

Ford used auto reset circuit breakers from the 30s clear up into the 50s. Early cars burned up mostly due to no circuit protection at all. Fuses will do the job but a person should carry a spare and find the problem before inserting a new fuse. Short Stop breakers were used in trucks clear up into the modern era due to all the lighting they had to have. I've seen them wear out over time but I've never seen a short circuit happen when a car is setting with everything off. If someone turns on a load and it trips the breaker then it's apparent that there is a short in that circuit. Find the short and repair it before turning the load on again.

A 16 gauge wire needs a lower amp rated fuse. Standard practices calls out a 10-amp fuse. A 15 or a 20 amp fuse would be better than a 30. A 15 amp circuit breaker is acceptable for a 16-gauge wire.