| Author |
Message |
MZ
Guest
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 Posted:
Thu Mar 03, 2005 5:50 am Post subject:
Re: Wiring options |
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| Quote: | Thanks for the regurgitation. And now that you explain nothing, so
you're saying it's better to put a 60 amp fuse on the inline batt for
an amp installed in the trunk of a limo drawing 60 amps?
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No. I'm saying if the wire can only handle 60 amps, then a 60 amp fuse
should be used. The length of the wire is completely irrelevant. It does
not change the current-handling capacity of the wire.
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Scott Gardner
Guest
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| Posted:
Thu Mar 03, 2005 6:39 am Post subject:
Re: Wiring options |
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On Wed, 2 Mar 2005 12:11:09 +0000, Vestax05pro
<Vestax05pro.1l9nbf@no-mx.caraudioforum.com> wrote:
| Quote: |
MZ Wrote:
Why don't you put a soup on your head and ride a bike, moron?
"Vestax05pro" <Vestax05pro.1l9k2o@no-mx.caraudioforum.com> wrote in
message
news:1109805754.b83b17cf744f0d36783ce6b04289bbff@teranews...
Electronic stuff? Nice way to put it......
And don't mean to be a grammar nazi but it's even harder to take you
seriously with "electronric". WTF is a electronric. Or would that be
electromagnetism and physics? Which you probably haven't taken in
college? Please GTFO and stop being an idiot.
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Lol - MZ is one of the more knowledgeable posters in this group, and
his mastery of both spelling and grammar is fine. His fractured
English in this thread is a joke on another poster that's been making
a pest of himself on here recently.
Scott |
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MOSFET
Guest
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| Posted:
Thu Mar 03, 2005 7:02 am Post subject:
Re: Wiring options |
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| Quote: | Actually, the length of the wire doesn't matter when determining the
proper
size fuse. It's not the resistance of the wire that's the issue, but
rather
the resistance per unit length (or, even more accurately, resistance per
unit surface area). This is because ultimately we're dealing with heat
dissipation as the factor governing what a wire can handle.
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Wait a sec MZ. The length of a given wire WOULD effect voltage, right?
Longer runs cause larger losses of voltage. So, if you had a very long run
and your voltage dropped considerably, wouldn't you need more amperage to
maintain a given wattage (Ohm's law)? So, length of wire WOULD effect
amperage. Is my reasoning flawed?
MOSFET |
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MZ
Guest
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| Posted:
Thu Mar 03, 2005 7:08 am Post subject:
Re: Wiring options |
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| Quote: | Actually, the length of the wire doesn't matter when determining the
proper
size fuse. It's not the resistance of the wire that's the issue, but
rather
the resistance per unit length (or, even more accurately, resistance per
unit surface area). This is because ultimately we're dealing with heat
dissipation as the factor governing what a wire can handle.
Wait a sec MZ. The length of a given wire WOULD effect voltage, right?
Longer runs cause larger losses of voltage.
|
Exactly right.
| Quote: | So, if you had a very long run
and your voltage dropped considerably, wouldn't you need more amperage to
maintain a given wattage (Ohm's law)? So, length of wire WOULD effect
amperage. Is my reasoning flawed?
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This would be true only if today's amplifiers were fully regulated and that
they were perfectly capable of maintaining their power output despite
fluctuations in the supply voltage. But most amplifiers today are only
semi-regulated, and what you find is that the power output decreases as the
supply voltage decreases. As a result, the current draw is technically
lower with higher resistance wire.
But all this doesn't matter, really. Fusing depends only on the properties
of the wire - how much current the amp draws is irrelevant because fusing is
done to protect the wire. The internal fuse protects the amplifier. |
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Scott Gardner
Guest
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| Posted:
Thu Mar 03, 2005 7:14 am Post subject:
Re: Wiring options |
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On Wed, 2 Mar 2005 18:02:20 -0800, "MOSFET" <ntanner@whidbey.com>
wrote:
| Quote: | Actually, the length of the wire doesn't matter when determining the
proper
size fuse. It's not the resistance of the wire that's the issue, but
rather
the resistance per unit length (or, even more accurately, resistance per
unit surface area). This is because ultimately we're dealing with heat
dissipation as the factor governing what a wire can handle.
Wait a sec MZ. The length of a given wire WOULD effect voltage, right?
Longer runs cause larger losses of voltage. So, if you had a very long run
and your voltage dropped considerably, wouldn't you need more amperage to
maintain a given wattage (Ohm's law)? So, length of wire WOULD effect
amperage. Is my reasoning flawed?
MOSFET
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The reduced voltage from a longer run will only cause the current to
increase if you have a regulated power supply in the amplifier. But
it doesn't matter anyway - Mark's right - the current-carrying
capacity of a wire isn't affected by the wire's length.
Let's say that 4ga wire can safely carry 135 amps of current. That's
going to stay the same whether you're talking about a two-foot run or
a twenty-foot run. That's why the current-capacity charts for wires
don't specify a standard run length.
Since the fuse near the battery for the main power lead is only to
protect the wiring, you just have to make sure that you use a fuse
that will blow before the wire is damaged. In this case, a 135-amp
fuse or breaker would do the trick.
BTW, voltage losses in the main power wire are pretty much negligible
anyway. To continue to use 4ga wire as an example, the resistance of
4ga is about a quarter-ohm **per thousand feet**. This means that
even if you had a twenty-foot run length of 4 ga wire and ran 135 amps
of current through it, you're only talking about a voltage drop of a
little more than half a volt. An amplifier with any kind of
regulation in the power supply won't even notice a drop that small.
Scott Gardner |
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MZ
Guest
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| Posted:
Thu Mar 03, 2005 8:30 am Post subject:
Re: Wiring options |
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| Quote: | To connect the Amplifer or a CD unit directly to the battery is like
a touch the burning fire with a bare hand.
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Man, that's deep. |
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Guest
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| Posted:
Thu Mar 03, 2005 8:30 am Post subject:
Re: Wiring options |
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Scott Gardner wrote:
| Quote: | On 2 Mar 2005 20:05:07 -0800, mmdir2002@yahoo.co.uk wrote:
Scott Gardner,
There is no such electronic theory of fuse protecting a wire.
NO electronic class taught such misleading theory.
The fuse is required from the power source to protecting the
electronic
device, and make sure that the current is not higher than required
by device. The fuse of car amplifier is only fuse you need to
protect
the amplifier from the battery. What you have is you got a fuse for
amplifier and another fuse for wire: Sound very stupid.
IN other word, you have two fuse in a serial wiring. That is so
awful setting. I've never heard of connecting one fuse and after
another.
That is so stupid. YOu are so stupid.
I will ask a simple question, and try to make it easy for you to
understand. If you have a power wire going from the battery to the
amplifier, and the only fuse is at the amplifier, what happens if any
part of the power wire shorts to ground?
|
Then that only fuse of the amplifier will be cut off.
| Quote: | That's right, you moron - the wire will burn through and the
insulation will catch fire. Your car will probably catch fire, too.
THAT is why any installer with a brain in his head puts a fuse in the
main power wire, right next to the battery.
Scott Gardner
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Let me play a devil advocate here. What you saying is you put
another fuse at the battery (the power source), there are two
ways power wire will cut off from the power source: 1) short it 2)
higher current. #1 is very obvious. You forgot the #2. The fuse
prevents from higher current to flow to the amplifier. But since
there is another fuse at the amplier, you don't need another fuse.
You only need one fuse to protect the amplifers. If you put a higher
rating fuse at the battery, this fuse will not protect the amplifier
because it does not operate at the amplifier's fuse rating
recommendation. Your thoery is nonsense. But I don't need
your theory because my amplifer is not connected to the battery.
To connect the Amplifer or a CD unit directly to the battery is like
a touch the burning fire with a bare hand. |
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MOSFET
Guest
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| Posted:
Thu Mar 03, 2005 8:30 am Post subject:
Re: Wiring options |
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| Quote: | I will ask a simple question, and try to make it easy for you to
understand. If you have a power wire going from the battery to the
amplifier, and the only fuse is at the amplifier, what happens if any
part of the power wire shorts to ground?
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Mmdir2002, if you cannot answer this simple question, you have no business
answering questions in this group.
You have more one chance with me because I sense in some of your posts you
are truly trying to help (though most here think you are hopeless). Please
think carefully before answering. Thank you.
MOSFET |
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Scott Gardner
Guest
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| Posted:
Thu Mar 03, 2005 8:30 am Post subject:
Re: Wiring options |
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On 2 Mar 2005 20:05:07 -0800, mmdir2002@yahoo.co.uk wrote:
| Quote: |
Scott Gardner,
There is no such electronic theory of fuse protecting a wire.
NO electronic class taught such misleading theory.
The fuse is required from the power source to protecting the
electronic
device, and make sure that the current is not higher than required
by device. The fuse of car amplifier is only fuse you need to
protect
the amplifier from the battery. What you have is you got a fuse for
amplifier and another fuse for wire: Sound very stupid.
IN other word, you have two fuse in a serial wiring. That is so
awful setting. I've never heard of connecting one fuse and after
another.
That is so stupid. YOu are so stupid.
|
I will ask a simple question, and try to make it easy for you to
understand. If you have a power wire going from the battery to the
amplifier, and the only fuse is at the amplifier, what happens if any
part of the power wire shorts to ground?
That's right, you moron - the wire will burn through and the
insulation will catch fire. Your car will probably catch fire, too.
THAT is why any installer with a brain in his head puts a fuse in the
main power wire, right next to the battery.
Scott Gardner |
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Guest
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| Posted:
Thu Mar 03, 2005 8:30 am Post subject:
Re: Wiring options |
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Scott Gardner wrote:
| Quote: | On 1 Mar 2005 23:35:14 -0800, mmdir2002@yahoo.co.uk wrote:
Fuse does not protecting the wire. Fuse is for protecting the
device.
Just read the manual of amplifier what it says about the fuse
rating.
Red Cloud (I'm going to start calling you by your old nickname, since
it's easier to type than mmdir2002@yahoo.co.uk),
You really have no business giving advice in this group. Some day,
someone is going to follow your silly advice and get hurt or set fire
to their car.
The fuse near the battery in the main power wire is NOT to protect
the
amplifier, it's to protect the wiring. The reason is, if you don't
have a fuse in the main power wire and any part of it shorts to
ground, the main power wire will catch fire.
That's why you put the fuse in the main power wire as close to the
battery as you can, so that the part of the wire that isn't protected
by the fuse (the part of the wire between the battery and the fuse)
is
as short as possible.
The amplifier is protected by its own fuses. The fuse near the
battery
is ONLY for protecting the wiring.
Scott Gardner
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Scott Gardner,
There is no such electronic theory of fuse protecting a wire.
NO electronic class taught such misleading theory.
The fuse is required from the power source to protecting the
electronic
device, and make sure that the current is not higher than required
by device. The fuse of car amplifier is only fuse you need to
protect
the amplifier from the battery. What you have is you got a fuse for
amplifier and another fuse for wire: Sound very stupid.
IN other word, you have two fuse in a serial wiring. That is so
awful setting. I've never heard of connecting one fuse and after
another.
That is so stupid. YOu are so stupid. |
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MOSFET
Guest
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| Posted:
Thu Mar 03, 2005 8:30 am Post subject:
Re: Wiring options |
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<mmdir2002@yahoo.co.uk> wrote in message
news:1109822707.940804.324650@l41g2000cwc.googlegroups.com...
| Quote: | Scott Gardner,
There is no such electronic theory of fuse protecting a wire.
NO electronic class taught such misleading theory.
The fuse is required from the power source to protecting the
electronic
device, and make sure that the current is not higher than required
by device. The fuse of car amplifier is only fuse you need to
protect
the amplifier from the battery. What you have is you got a fuse for
amplifier and another fuse for wire: Sound very stupid.
IN other word, you have two fuse in a serial wiring. That is so
awful setting. I've never heard of connecting one fuse and after
another.
That is so stupid. YOu are so stupid.
|
I really can't believe I'm wasting my time responding to you....
Mmdir2002 (or Red Cloud, or whatever), we have all given you many reasons
why the power cable to an amp is fused at the battery, and I'm not going to
go through it again. I have to think that you are just yanking all of our
chains as you could easily research this yourself and know that WE are
right.
Why do you do this? Please leave and go somewhere else.
MOSFET |
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MOSFET
Guest
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| Posted:
Thu Mar 03, 2005 9:50 pm Post subject:
Re: Wiring options |
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<mmdir2002@yahoo.co.uk> wrote in message
news:1109834856.755096.131530@g14g2000cwa.googlegroups.com...
| Quote: | To connect the Amplifer or a CD unit directly to the battery is like
a touch the burning fire with a bare hand.
Do mean it's like Chariots of Fire? Or, is it like, Iccaris, who spread his |
wings and flew to close to the fire of the sun?
What if I want to touch the Burning Fire? What if I want to stretch my
bare hands out and grasp the forbidden Buring Fire and run, run like the
wind so that no man may match my furry?
Is this what you mean?
MOSFET |
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MZ
Guest
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| Posted:
Thu Mar 03, 2005 9:53 pm Post subject:
Re: Wiring options |
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| Quote: | Do mean it's like Chariots of Fire? Or, is it like, Iccaris, who spread
his
wings and flew to close to the fire of the sun?
What if I want to touch the Burning Fire? What if I want to stretch my
bare hands out and grasp the forbidden Buring Fire and run, run like the
wind so that no man may match my furry?
Is this what you mean?
MOSFET
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Go ride a bike! |
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srw101
Guest
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| Posted:
Thu Oct 13, 2005 10:56 pm Post subject:
Re: Wiring options |
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1,2,3 and to the 4ohm Wrote:
| Quote: | ok i understand what u are saying in all, but the sub manufacturer says
that the subs can only be operated at 2 or 8 ohms. so wouldnt tha
hurt
the subs making them go lower than they are supposed to? I dont know,
maybe they can be maybe they cant be., thanks for the post hope t
keep
getting more feedback from knowledgable people!
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Sorry, not to stir anyone up but I found this thread in a search an
this is one funny *** thread. This guy mmdir2002@yahoo.co.uk has dow
syndrome or something! Definitely good reading material for basi
battery fusing too
--
srw10
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