Most DC breakers do not react as fast as a fuse. As you are back feeding circuits not designed to be used this way you can increase the chance of damaging things. Wiring to the stock cigarette lighter socket will begin to melt with a sustained 10 to 20 amp load. I would suggest using test lights and ohm meters to look for those short circuits.  

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Steven Shelton
Sent: Wednesday, July 1, 2015 10:26 AM
To: vanagon@GERRY.VANAGON.COM
Subject: 12V Circuit Breaker

I test my electrical work and 12V devices using a jump starter battery and a cigarette lighter plug with two alligator clips attached.  The plug has a Buss 10 amp fuse in it.  My limited electrical knowledge results in a lot of blown fuses.  Is there a 10 amp breaker that I could wire into the tester so I won't have to keep buying boxes of Buss fuses?