When running direct to the battery I always fuse the positive and negative legs.

 

When running direct to the battery I always fuse the positive and negative legs.

Agreed and I ran cobra 75 straight to battery and have good results.

 

Will also help to cut down on the interference and white noise in the receiver too.

 

I have always fuse the Pos & Neg side of the Radio(s) etc... , But until reading Slim_Snoopy comment about it needing to be on the engine side due to a short closer to the battery I had never thought about it that way. So In saying fuse the 12V and GND it really is Fuse the battery more then fuse the Radio... or what ever it is your doing..
So to make it simple I guess one should run a fused terminal block off the battery and connect items to that... and fuse those items also... I guess even add an added fuse block...
I need to look in to that.. It would make it alot cleaner when I go to add lights... etc..
does that make since...??? also for those that have a winch did you do something special for that.... A little off the topic maybe but power to radios is very important....etc..

 

I haven't climbed under the dash to look yet but is there already a hole to thread the CB wires through to the battery or am I going to have to drill?

 

Take off the passenger side panel and you can see a small circle with yellow foam in it. Just take a coat hanger to the foam and punch a hole through it

 

Cool! Is there a trick to getting that side panel off? Is it screwed on or does it just pop off?

 

Just pops right off. i found its best to remove the AC vent, then pop it out thro the AC vent hole

 

I am sorry, I don't mean any disrespect I really don't. When running Power the only power wire running to the Battery needed is the Positive. The negative does not need to run to the Battery The Negative can be connected to anywhere you have a good frame ground. As far as fusses go You want to have 2 fuses one at the Battery and one at the Radio! The reason behind that is because if you get a short, the fuse closest to the least path of resistance will blow... You want that because if something is wrong with the radio then the fuse at the radio blows and if it is with something like if the positive starts to ground out on the frame then the fuse at the battery will blow. Prevent a car fire so you want to double fuse.... Now as far as putting a fuse on the ground doing so is useless because the radio is grounded internal to the radio enclosure which grounds through the radio bracket then to metal(usually) and also you have a ground running through the antenna.... With that being said Make sure you still hook up the Ground power wire even though you have those other grounds....

 

Why fuse the negative lead? VERY good question. I'll try to explain.

Vehicles use the chassis/frame for some of their DC grounds. The negative lead of the battery is attached to the chassis and usually the engine block. The case of the starter motor is often times the ground connection so it gets its ground, back to the battery, via the block. This works fine.

What would happen if the chassis/ground connections between the negative lead of the battery and the starter became bad....or, more likely, started to get some resistance in it? The starter would have more trouble turning over the ending due to the voltage drop across that part that has a bad connection (aka., resistance).

Now...go one step further. You mount a radio in your vehicle. The power leads go directly to the battery (as they should) or to a nearby aux fuse block that was installed by you to handle your extra goodies.

The antenna is mounted on another part of your vehicle and its mount is grounded to the vehicle's body/frame (in order to work properly). The coax connects the CB radio chassis and the antenna together....and the outer coax braid is at ground also (but it is covered with an insulative coating).

OK...back to earlier in the explanation. You have a heavy current carrying device...like a starter....or maybe a light bar that is grounded to the vehicle body for the negative connection for that batch of off-road lights it is holding up. If the negative battery cable that goes to the block/chassis starts to go bad, the DC current flowing from one of these items...let's say the light bar), can find a ground through the body of the vehicle to the antenna mount and down the antenna coax and through the CB chassis/circuit board ground and through the CB negative power lead to the battery itself.

When that happens, you might very well have 30~50 amps of current flowing through the CB radio's chassis, trying to get to the negative terminal of the battery. If it were the starter motor that found its "other ground path" through here, you would have a couple hundred amps flowing.

The end result is that your CB chassis, with those tiny copper circuit board runs on it, can become a fusable link and burn open due to the excessive current flowing through the ground circuitry of your radio chassis. So...you burn out the guts of your radio.

By putting a fuse in the negative lead of your CB radio (or ANY other electronic device that is attached to the battery), it will blow open and stop the high current flow before it does any permanent damage. (just like the positive lead fuse will blow open if you shorted the hot lead to ground).

If you don't believe this, please feel free to stop by my house. If you volunteer your vehicle and radio, I shall be happy to do the "faulty ground wire" scenario on your vehicle. You can turn on the lights or crank over your engine and watch your CB radio smoke.