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Where to put fuses in a dc circuit? Answered

Say I have a 12 volt battery and I want to connect a light and a radio.  Should I put a fuse next to the positive or negative terminal of the battery?  Or should I fuses in front of everything.  DC current flows from pos to neg right?  so I would put the appropriate fuse on the positive side of each electronic device?    
Thanks

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Dr.Bill

Best Answer 7 years ago

All my equipment is fused individually on the positive (red) wire.
If you want to fuse the Positive side wire off the battery too its OK.

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Lazarusnumber2

5 months ago

VOLTAGE FLOWS FROM NEGATIVE TO POSITIVE, AND I JUST USE A 60 AMP FUSE IN A CLEAR COVERED BOX ON THE NEGATIVE SIDE HOOKED UP TO THE BATTERY BEFORE IT (BATTERY) IS GROUNDED TO THE FRAME, SO EVERYTHING I PUT ON THE POSITIVE SIDE IS FUSED UP TO 60 AMPS AND SOMETHING LIKE A RADIO SHOULD BE FUSED WITH A LOWER AMP FUSE WHICH YOU COULD PUT A LOWER AMP FUSE ON THE RADIO ON ETHER SIDE (+) or (-) If You know the amps on everything on it which I don't know what this applies to, You can put in a fuse box to fuse everything on it separate circuits. YOU COULD JUST PUT A 60 AMP FUSE TO GROUND THE NEGATIVE TO THE FRAME, and just a couple lower amp fuses for things like a radio, which can be installed in line on ether side of the item You want to protect from too many amps thus burning it out.

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frollard

7 years ago

Seconded. It will work on either side, but in series with + is most common.

"current flows from pos to neg right?" -- Depends, current 'technically' flows from - to + (electronis are negative, and they are the part that moves). In the old days it was thought that there was a positive particle that moved so "conventional current" is + to -. These days many schematics use the same old symbols that indicate the direction of conventional current (transistors, diodes, etc) but it's important to understand the difference.

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Jason_Knightefrollard

Answer 4 years ago

That is good to know man. Thanks for the help I was wandering the same thing, and its working, so I am happy with it.

Jason.
http://www.bionicautoparts.com/

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steveastroukfrollard

Answer 7 years ago

Tut tut. Are you talking about majority or minority carriers ?Conduction in solid metals is by electron flow sure, but not for a lot of other things.

http://amasci.com/amateur/elecdir.html

Steve

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NachoMahma

7 years ago

. Is fusing the positive side a standard (a Q&D search didn't turn anything up) or just convention?

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frollardNachoMahma

Answer 7 years ago

Every fuse I've seen has been on the hot side of AC, or non-ground side of a DC circuit. Probably just convention.

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orksecurity

7 years ago

Fuse goes in series with the load, to protect the power supply if the load shorts out. Positive or negative side doesn't matter; fuse responds to excessive current, not voltage or polarity.

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Re-design

7 years ago

In a circuit like this it doesn't matter.