Circuit Breakers for Electrical troubleshooting

Dave in Boise

Dave in Boise

Senior Member
Hi All,

Had a fellow PM me on a source for self-resetting circuit breakers that can be snapped into the fuse holder many of us mount on our starters.

I use them to do work on the electrical system and to help me chase down ghosts and shorts in the wiring without having to buy a whole package of glass fuses..

No relation to this company, but seem to be a very good vendor and their product has helped me in fixing my own cars and others as well..

here's the link where I bought them..

http://www.rvupgradestore.com/30amp-Snap-in-circuit-Breaker-p/56-1107.htm


These are 30 amp, but they have them starting at 15 amp and go up to 40. I carry both a 15 and 30, as the 15 is more sensitive, you can use it to isolate smaller shorts without smoking the wires.. As they are thermal and self resetting, if you snap in a 30 amp and go for a drive on a hot day, the engine heat can cause them to shut off untill they cool :) .. Don't ask me how I know (lol)

I initially used them as permanent replacements for fuses, but discovered this thermal sensitivity, so still have them on board, but in my troubleshooting kit

- Dave in Boise
 
i use them all the time with no trouble (permanate) . they are great to let you find the problem .
 
Good idea for fuse as sometimes hard to find fuse when they blow. The reason they are heat sensitive is that they use a bi-metalic strip between the contacts so when gets too hot due to current flow they open. Same as breakers in your home. A simplier way to find shorts is rig up a 6V or 12V light bulb depending on your battery and put alligator clips on wires attached to the bulb. Connect the bulb across the fuse terminals or from battery to main power wire if no fuse. If light glows there is a current draw. Keep removing things until the light goes out and problem solved.
 
I love you guys for helping me convince folks that a circuit breaker is a Good thing to protect your car's wiring & is a GREAT diagnostic aid when you have a short or an excessive current draw. A 30 Amp was sufficient on my "30 Coupe. Bill W.
 
Used to use a turn signal flasher in the fuse holder and turn a transistor radio off station.. Follow along the wires till you here the flasher in the radio static and bingo, short was right there.....
 
Of course this may come across the wrong way and if it does I apologise.

I never use a circuit interrupter such as a circuit breaker or a fuse as a diagnostic tool. Doing so sounds down right dangerous should the device fail. They are designed as a last resort emergency device and in reality should never trip. I have also seen circuit breakers stick on which is why I insist on fuses when possible in my designs.

I use a simple ohm meter to troubleshoot any circuit before power is applied to it. In the case I am testing a circuit I use a variable power supply or a variac and slowly apply voltage to the circuit while monitoring current draw.

And yes, this is how I work on our "A" as well.
 
milo said:
Used to use a turn signal flasher in the fuse holder and turn a transistor radio off station.. Follow along the wires till you here the flasher in the radio static and bingo, short was right there.....
Click to expand...
Yo, milo,
The mad inventor at work,:p very trick!:D
For those that need "hearing" glasses,:confused: an old smoke alarm buzzer with alligator clips makes a great continuity tester. It even gets the neighbors out of their "cave!" My vintage transistor radio tells me if I'm losing spark to one cylinder! :eek: Bill W.
 
If you want to help a kid out my son is selling them to help fund his restoration but they are $10.00 + 2.50 shipping from him.
 
My electrical knowledge if on permanent short circuit so does it make any difference if 12 v breakers are used in a 6 v system?
 
Pete said:
R om. ur sig qrk 5. rig hr is hm brew.
73
Click to expand...
Pete,
THE ABOVE?????:confused: Is that code for"TWISTED SHORTS??":eek:
Chief described electrons as: "Those little men that run in the wires, making electrical things happen. They can only run in one direction, from positive +, to negative -. When they encounter an open, they get "TWISTED SHORTS,":eek::eek: 'cause they cain't get across & cain't go back 'cause the Battery Boogie Man will gettum.'
This can be found on page 3 of CHIEF'S ELECTRICAL-101. Bill W.
 
A head light sealed beam is good for chasing shorts. You just connect the beam across the fused connector, without the fuse in place. The light will illuminate when the short is present and off when no short is to be found. Its works well in looking for the intermittent problem.
There are also flying shorts too. (They are not pants to be worn in a plane)

Ross
 
You must log in or register to reply here.
Back
Top