High Power Fusing

[Kojak]

fuses = voltage loss.........

do a good clean install and there is really no need for
a fuse........im running a 2x6 in my truck no fuse guna
install a 1x4 in my semi this week sometime no fuse
and my base im running a 3x8 no fuse, and if i can find
something to run my 12 pill in its not going to have a fuse
either.......it is kind of a safety devise to leave yourself
room for error but i just double check everything and go
with it........been doing it that way for 5 years and so far
i havent smoked nothing but 1 pill in my 8 pill.....and yes
its a Davemade and yes their pills will also blow just as
any other amps will

Data please....

[PONY EXPRESS]

fuses = voltage loss.........

do a good clean install and there is really no need for
a fuse........im running a 2x6 in my truck no fuse guna
install a 1x4 in my semi this week sometime no fuse
and my base im running a 3x8 no fuse, and if i can find
something to run my 12 pill in its not going to have a fuse
either.......it is kind of a safety devise to leave yourself
room for error but i just double check everything and go
with it........been doing it that way for 5 years and so far
i havent smoked nothing but 1 pill in my 8 pill.....and yes
its a Davemade and yes their pills will also blow just as
any other amps will

They must have made Fuses for some reason...................
Homes are fused or circuit breakered & automobile inductry fuse .Must be a reason ......

[lonesome 500]

fuses = voltage loss.........

do a good clean install and there is really no need for
a fuse........im running a 2x6 in my truck no fuse guna
install a 1x4 in my semi this week sometime no fuse
and my base im running a 3x8 no fuse, and if i can find
something to run my 12 pill in its not going to have a fuse
either.......it is kind of a safety devise to leave yourself
room for error but i just double check everything and go
with it........been doing it that way for 5 years and so far
i havent smoked nothing but 1 pill in my 8 pill.....and yes
its a Davemade and yes their pills will also blow just as
any other amps will

fuses = voltage loss.........false

[3strucking]

i am not going to disagree with the voltage loss as i am not sure, but it seems to me that if you start with your charging system and make sure you have big enough power and ground wires what little bit of loss may be there wont matter. I dont understand why someone would do it backwards as in go buy a 12 pill and use a 70 amp alternator and 8 gauge wire to supply it, then wonder why they have problems. I know that alternators, batterys, and wire cost a great deal but if you do it right the first time and go ahead and buy everything larger than you need, when you do upgrade latter there is no problems. I will always fuse atleast the hot side of everthing I have. I would rather loose a little power than burn up my $150,000.00 peterbilt.

[lonesome 500]

if a fuse causes voltage drop......it creates heat.........then blows or melts from heat failure

ANL fuses go to at least 1000 amp......or that's the biggest i've seen

[Foxhunter]

Fuses...

There does seem to be a small degree of voltage-drop associated with fuses, depending on the type and characteristics of the choice utilized by the selected fusing. In most cases it is not large, but it does depend on the type of fuse used. Certainly not all fuses "are created equal" and that probably can't be stressed enough.

I'd really encourage anyone interested in DC fusing and characteristics to read these small informative articles below I've linked from files saved to my desktop about fusing and various fuse characteristics. All articles ultimately in the end recommend fusing. But see why and which types specifically.

Personally, I eliminated all puny "stock fuses" on all of my amplifiers because I felt and agreed they were rather weak----as provided from the manufacturer. I eliminated them at the amplifier while at the same time upgrading my supply cable sizes. The amplifiers all get fused on both (+/-) lines at the battery with very high quality & expensive UL-listed (gold-plated contact) fuses designed for high-demand car audio amplifiers.

Technically in a perfect world we would not need fuses, but it is very much like driving without car insurance where one incident then can spell total disaster. A definite gamble and "roll of the dice" and I personally don't feel comfortable going without some form of insurance like fusing. My decision was to use the best possible quality fuses I could find period, and didn't be a cheap-skate when making selection.

At one time from my experience doing car audio amplifier installations I used the re-settable DC circuit breaker panels in a CB & amp install. They are very convenient to use and just trip instead of burning up fuses. But after reading about the dangers associated with using them I switched back to fusing but increased the quality of the fuses & holders. It would seem they can arc over and weld themselves closed to re-complete the circuit resulting in disaster. These breaker panels are excellent in some applications still I imagine. I did like them.
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It's interesting how widely varied so many fuses are from internal resistance, voltage handling (both high & low voltage type-rated fuses), fuse opening reaction times (critical) and more.

About the reaction times for instance, "note that a 30 A Maxi fuse will take about 3 seconds to open when subjected to a 100 A load! The same fuse will carry 40 A for about 2 minutes! So, there is a time lag between applying an overload, and the fuse opening to protect the wire. Enough to allow harm to a sensititve electronic device."

As a general statement, what are the fuse-type ratings & characteristics "protecting" your gear ?


Are You Using the Right-Sized Fuse?
by Alan Applegate K0BG & ARRL (3-page PDF File)
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The DC Wiring Page: Connectors, Fuses and Wire
by Emergency Measures Radio Group ARES
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Focusing On Fuses
by John Stiles & Photovoltaic Systems Assistance Center (3-page PDF File)
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[3strucking]

i use fuses and holders mfg. by littelfuse. There megafuses are hard to beat. the only problem is if you use there midi and mega series you have to use the holders that are littelfuse also because a mega wont fit in a anl holder and the midi is just a smaller version of the mega. On the positive side the littelfuse brand is the highest quality that i have found and yes they are a little more expensive, but when you have $2000 in you mobile system why skimp on the fusing?

[127]

Hello all, just wondering, how does the big amp crew fuse their stuff? I have a 300 amp breaker I plan on using, but at 300 amps, I'd think the vehicle would be burning down by the time it tripped itself in the event of a short. Any thoughts on this? Do they just run it all direct and disconnect when not in use? I can understand a much lower rated fuse or breaker used for safety, and I use them at the equipment and the battery, but what about this higher amperage stuff? I typically unhook my stuff when not in use anyway, as it is on welder connectors, no big deal, but I'm moving to a more hard mounted setup. -drdx

No one around here fuses their keydown mobiles but then again most of them are all trust fund CBers and in the event of a vehicle burning up.........they'll just buy another.
Fuses are not meant to protect equipment, just keep the vehicle from flaming up in the event of a dead short.
I don't fuse anything....I have a 92 F350 with half a million miles on it, no big loss if it smokes.

Even if I had a POS truck, I would still fuse all hot lines. What if you are in the middle of nowhere and the truck flames up due to a short..........you see my point?
I fuse everything with ANL fuses.

[c+c]

i feel safer with a fuse .i was into car stereo be for i came back to cb. so what i did is used the same wire set up. i got 4 guage wire 100 amp fuse block . i cut the wire to my desired size and used the two way splitter that down sizes gauge wire the run my amp on one and radio on other .i dont notice any power loss i have to have my car running to set full power on amp but if thats the worse case oh well. i made it clean install and use 0 gauge wire for my grounds [bit over kill but im i no im grounded well]but that was easiest way for me and great results!

[626]

Ok old thread but, I have a great link to the best high power fuses and junction blocks I have found. Check it.....

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If you cant find a fuse or junction block here you are lame.

GUNNY

[linearone]

the big power folks do not fuse their equipment. sounds stupid but it does cost watts. ANL fuses like the above are awesome

[jessejamesdallas]

the big power folks do not fuse their equipment. sounds stupid but it does cost watts. ANL fuses like the above are awesome

OK...How can it cost watt's, or a voltage drop? All a fuse is, is a bridge that will pop if too much voltage or a voltage spike hit's the bridge...If your running 14v's threw a fuse, your going to have 14v's on each end of the fuse...You may have a voltage drop from the time the voltage leaves the battery, and gets to the Amp (or device) because of the feed wire. But I don't see how a fuse will cause the drop...

Like on my work van, I can check the voltage to my battery under the hood when the motor is running, and it will show 14.3v's...But if I go and check the voltage at my battery bank in the back of the Van, the voltage will be like 13.3v's...I loose a whole volt because of the length of the cables running from the front to the back. (which is probably around 12'+) Think they call that resistance...Now there are fuse's in line...But I was seeing the same voltage drop "Before" I put the fuse in-line...There is always the possibility that I could cut that volt loss down some by going to a larger charging cable, but if all I loose is one tiny volt, I'm not going to worry too much about it...(plus, I don't think I'm going to be doing much Competition Key-Downing in my work van!)

Now..."IF" there is loss from using fuses, It would be so small, that Not using a fuse would be just plain stupid IMO, and a good way to have a major melt-down when it could have easily been avoided...

[linearone]

the big power folks do not fuse their equipment. sounds stupid but it does cost watts. ANL fuses like the above are awesome

OK...How can it cost watt's, or a voltage drop? All a fuse is, is a bridge that will pop if too much voltage or a voltage spike hit's the bridge...If your running 14v's threw a fuse, your going to have 14v's on each end of the fuse...You may have a voltage drop from the time the voltage leaves the battery, and gets to the Amp (or device) because of the feed wire. But I don't see how a fuse will cause the drop...

Like on my work van, I can check the voltage to my battery under the hood when the motor is running, and it will show 14.3v's...But if I go and check the voltage at my battery bank in the back of the Van, the voltage will be like 13.3v's...I loose a whole volt because of the length of the cables running from the front to the back. (which is probably around 12'+) Think they call that resistance...Now there are fuse's in line...But I was seeing the same voltage drop "Before" I put the fuse in-line...There is always the possibility that I could cut that volt loss down some by going to a larger charging cable, but if all I loose is one tiny volt, I'm not going to worry too much about it...(plus, I don't think I'm going to be doing much Competition Key-Downing in my work van!)

Now..."IF" there is loss from using fuses, It would be so small, that Not using a fuse would be just plain stupid IMO, and a good way to have a major melt-down when it could have easily been avoided...

try it and see.

[Foxhunter]

It's true, fuses do cause voltage-drop and are a narrow "bottleneck" of the supply line. In most cases I am all for safety and have many of my things fused. However there is enough of a drop present in a given fused line that recently I removed two inline fuses from two different amplifiers. Keeping fuses inline, or removing them completely-----will be up to the individual user but some guys (gamblers) will rather operate without them, exchanging risk for increased performance. Not that much, but it is a measurable amount.

Think about it-----you may have two heavy gauge supply lines, but then all that current and voltage is to pass through a much much smaller filament section-----far smaller than the gauge of the supply lines themselves. A definite bottlenecking of power, but not enough for many guys to worry about and they leave the line remaining fused. It is true that many of the comp guys don't fuses for the very reason of that small voltage drop that occurs across a fuse. Like in a coaxial cable system also wiring has an insertion-loss with multiple connections and it's often best to minimize the number of connections made in a line.

Voltage drop
"The values of the voltage drop across a fuse are usually given by the manufacturer. A fuse may become hot due to the energy dissipation in the fuse element at rated current conditions. The voltage drop should be taken into account particularly when using a fuse in low-voltage applications".

[Double J]

Ok, I need help - last ime I wired a TRAM radio and a 150 watt Linear was in the early 1970's.......
Now - I have an F150 Ford truck and am trying to do the wiring correctly; so....

1. I bought one Oddysey battery with 1750 CCA ( battery place said Optima was last years best battery - go with this years best )
2. Bought a high output 250v alternator
3. Bought an RCI 69FFC2 radio ( from e-bay~ deadkey 25 watts & supposedly peaks at 325watts, tuned by Sparky's CB shop)
4. Am considering getting a TS sweet 16
5. Ordered RG8x Commercial grade coax
6. Currently running a 9ft metal whip antenna; considering a ground plane three prong thing at base of antenna....

Thinking about using 4 gauge wire to run power from Batt to Radio ( and Texas Star when I get it)

Will use a central ground for all equipment, and use ground cabling to make sure cab, truck bed, toolbox, etc are all grounded... antenna is currently mounted on diamond plate toolbox

I know I need fusing and have been thinking about going to a stereo shop for those large fuse holders they use in stereo amplifiers..... but
HELP.....What size fuses do I need?...
a. close to battery on radio power line
b. close to radio ( use fuse recommended by RCI Radio? )
c. Close to battery on Sweet 16 power line
d. close to Sweet 16

Thanks
Double J