To fuse or not to fuse (split from memorial day install)

Post by **ttocs** » Sat Jun 26, 2010 2:25 am

I do not care who you cite, what you say, I will ALWAYS follow the golden rule of power wire and fuse it right after the battery.

I also would like to know how come a longer run is more likely to short out? do you mean because there is more wire there is a bigger chance that that the insulation could be pierced?

shawn k · Post by **shawn k** » Sat Jun 26, 2010 7:54 am

dedlyjedly wrote:
shawn k wrote:
If it's not in the "rule book" IASCA, USACi, MECP or otherwise, the book should be thrown in the garbage. Espeacially MECP... Horrible company!!

It's basic fundamental 12v wiring
It seems that I agree with your opinions on basic fundamental 12v wiring, but certainly not with your assessment of MECP! What do you have against that organization?

Man I just spent an hour writing up why I have issues against MECP and I lost it since I accidentally clicked the LOG IN/OUT

Basically the short version is this: They allow people to pass the exam, even the Advanced exam, at install shcools who practically give the students the answers. I've quized friends and co-workers who are "Basic" and "Advanced" certified and quite frankly they have no clue

Passing an exam, especially something like MECP does not in the least mean you have sound installation skills nor does it mean you can even remember anything that you have studied.

I belive MECP's intentions were legit in the beginning, but I feel now it's nothing more than a marketing gimmick and, like many companies, their just out to make a buck. Why does MECP allow students to take an "Advanced" exam BEFORE the 1 year experience prerequisit AND when they clearly cannot pass a Basic exam on their own? The answer is simple...$$$ It's no longer credible. Sure it may be fools gold in the eyes of the consumer when he sees a nice framed certification on the bay wall, but I would never hire an installer based on whether or not he/she is certified.

From personal experience if feel there are far too many ceritfied installers (even advanced ones) out there that don't even have a clue about ohm's law, basic fundamental wiring, or proper install adequate.

I got my First Class (aka Advanced) certificate many years ago. To be honest, I've never even displayed it at my work place. It's the confidence, experience, and professionalism that will land you the big jobs. No certificate, at least for our industry, can beat that.

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Post by **ttocs** » Sat Jun 26, 2010 10:03 am

I can agree with that but on the other hand I have taken my car to some master certified mechanics that couldn't tell their ass from their elbow. When I graduated college I was almost embarrased at some of the guys that gradutated with me as they struggled with basic algebra but somehow managed to get through and get the same piece of paper I had.

I was mecp basic certified back in 94 because BBY paid for it. Back then the tests were a little more advanced as they included all the celular stuf that is not in today. I never did go back for any further because non of the shops I went to cared and I am 10x the installer I was there with the experience I gained since then.

I am not sure why you would not expect to be given some very good study guides for the mecp test after paying what the schools charged. even if they hand them the answers they still have to have some kind of an idea of what is going on but with that said I am sure there are alot that cheated their way through it. I do not look any differently at an installer with a cert or with out.

I would still like to see the rule that there is no fuse necessary on the 2nd battery, and almost willng to bet on it and I never bet.

jbob0124 · Post by **jbob0124** » Sat Jun 26, 2010 10:28 am

Rules are rules, but how many of us here are following the rule book line for line?

I thought this thread was about one amp and alot of subs?

shawn k · Post by **shawn k** » Sat Jun 26, 2010 10:28 am

ttocs wrote:I can agree with that but on the other hand I have taken my car to some master certified mechanics that couldn't tell their ass from their elbow. When I graduated college I was almost embarrased at some of the guys that gradutated with me as they struggled with basic algebra but somehow managed to get through and get the same piece of paper I had..

Exactly! I'm fortunate enough that my good friend is a full time mechanic, but I assure you that if I did need someone I would do a little research to see who's the best around. I would not base my research on whether or not the mechanic is ASC certified.

ttocs wrote:I was mecp basic certified back in 94 because BBY paid for it. Back then the tests were a little more advanced as they included all the celular stuf that is not in today. I never did go back for any further because non of the shops I went to cared and I am 10x the installer I was there with the experience I gained since then.

No doubt. Can't beat experience. Exactly what I was referring to before

ttocs wrote:I am not sure why you would not expect to be given some very good study guides for the mecp test after paying what the schools charged. even if they hand them the answers they still have to have some kind of an idea of what is going on but with that said I am sure there are alot that cheated their way through it. I do not look any differently at an installer with a cert or with out..

The MECP study guide is usually included with the tuition fees for these schools. Believe me, some of these installers barely have a clue even though they're certified. What really sets me off the deep end is when MECP allows inexperienced students who have not even entered the field yet to take these "Advanced" exams immediately after taking the Basic and only passing because they are carried through it

This is just their way of making more money and in the long run has only devalued their credibility.

ttocs wrote:I would still like to see the rule that there is no fuse necessary on the 2nd battery, and almost willng to bet on it and I never bet.

Don't count on it.. I'm sure there's nothing writen like this (and even if it is it's wrong). Keep in mind that the phorum member who was arguing that a second fuse is not necessary IS "first class" certified. Sorry to call it out like that, but this is EXACTLY why I can't stand MECP

Post by **ttocs** » Sat Jun 26, 2010 11:24 am

I can agree about the people the schools are turning out as the last shop I worked at in phoenix like to hire them from the local school there, can't remember the name now. If these guys had not gone to the school the owner would not have even considered them as they were green as can be. I would not expect any school to teach you everything, and that goes for any school not just audio related. Having a degree or certification does not mean you know everything it just shows that you have shown a willingness to learn and and the ability to do so. The install schools are just an easer way to get your foot in the install bay then the traditional way that I did by starting selling and working my way back(as became less tired of dealing with customers and wanted more money).

we loved razzing the kids though, sending them out looking for the wire stretcher and 6x8 hole saw and suck. Their eagerness to learn and to prove themselfs as well as to suck up to the regular installers would make them believe almost anything we told them

...

shawn k · Post by **shawn k** » Sat Jun 26, 2010 11:42 am

ttocs wrote:we loved razzing the kids though, sending them out looking for the wire stretcher and 6x8 hole saw and suck. Their eagerness to learn and to prove themselfs as well as to suck up to the regular installers would make them believe almost anything we told them ...

LMAO!

damn.. why didn't I think of that

yeddy · Post by **yeddy** » Sun Jun 27, 2010 8:01 am

This is right from the pages of my Kinetik power cell manual. This is pretty simple really, if your power wire shorts through the firewall your main battery will be saved by the fuse in the front, without a fuse at the rear, the rear battery will become a swollen smoldering melted mess! Try hooking up the + right to the frame, see what happens... The local store where I bought my powercell from had run into this problem and showed my the battery that was in the back of a car. What twisted mess!! Think logicaly here guys... In the end of it all, there is waaaaay to many "pro" installers that don't even think with logic!

Xtra credit to Nick for the secondary battery fuse!!!

I love the setup man, pound on brotha!

shawn k · Post by **shawn k** » Sun Jun 27, 2010 8:08 am

yeddy wrote: Think logicaly here guys... In the end of it all, there is waaaaay to many "pro" installers that don't even think with logic!

Amen to that!

dBincognito · Post by **dBincognito** » Sun Jun 27, 2010 8:35 am

I never use a fuse between the battery, I would use a breaker there. It also does not show any fuse before the amp, which is where a fuse is needed the most.

your power wire shorts through the firewall

I've never even heard of this being a problem, I always use weather tight grommet's and I don't even think it shorting through the firewall is even a option, never heard of it happening before.

(provided they don't have fuses themselves)

You always fuse within 8 inches of the amp, the onboard fuses will NOT stop the current. Your amp will fry if those fuses pop.

str3atwarrior · Post by **str3atwarrior** » Sun Jun 27, 2010 8:40 am

With a grommet there's virtually no risk. But i've seen some stupid person when i was working in industrial automation that were simply drilling a 1/2 hole in the panel, and passing wire freely in it. And when you're speaking about 600V AC power cable, and vibration, i've seen some really bad messed up panels.

The good thing is, it was making work for us

So if you just pass the wire by the firewall without grommet, this could/will happens from vibration, but when done right, there's virtually no chance of this to happens...

Just my 2 cents :p

shawn k · Post by **shawn k** » Sun Jun 27, 2010 8:42 am

It doesn't necessarily have to short at the fire wall. Basically the fuse in the rear is to protect from any short due to an unforseen mishap (like getting in a car accident for example) If one does not believe in fusing a battery in the rear of the vehicle, then this same person may as well forget about a fuse under the hood just the same.

str3atwarrior · Post by **str3atwarrior** » Sun Jun 27, 2010 8:46 am

Don't get me wrong, i'm always fusing wires that could be at risk, since fuse is a protection, and one thing i've learn is that you can never have too much protection! Much better getting a 50 cent fuse to blow than a thousand bucks of equipment fried! (Well a PLC in industrial automation can go from 1000$ to more than 50 000$ so not fusing is not even an option!!)

shawn k · Post by **shawn k** » Sun Jun 27, 2010 8:52 am

dBincognito wrote:I never use a fuse between the battery, I would use a breaker there. It also does not show any fuse before the amp, which is where a fuse is needed the most.

Good catch.. there should be a fuse between the amp and the battery (especially if there's a decent amount of length between them)

Circuit breaker/fuse.. both will protect from shorts therefore one is not superior to the other.

dBincognito wrote:You always fuse within 8 inches of the amp, the onboard fuses will NOT stop the current. Your amp will fry if those fuses pop.

On board fuses will protect the amp just as well or just as bad as a fuse that's "within 8 inches" of the amp. Current flow is insanely fast and the difference between a fuse at the amp or withing 8 inches is absolutely negligable!

dBincognito · Post by **dBincognito** » Sun Jun 27, 2010 8:59 am

On board fuses will protect the amp just as well or just as bad as a fuse that's "within 8 inches" of the amp. Current flow is insanely fast and the difference between a fuse at the amp or withing 8 inches is absolutely negligable!

I beg to differ, it will jump right past the fuse and fry the circuit board. Electricity will take the shortest, easiest route......and if you don't have a fuse within 8 inches of the amp.....the shortest route is straight through the amp, it will not travel all the way back to the fuse at the firewall, it will cook the amps. It's not much of a jump from the onboard fuses to the circuit board. This is why fusing next to the amps is so important, if you get rear ended it's the only thing that will save the amps.

Post by **ttocs** » Sun Jun 27, 2010 9:09 am

under normal conditions with the correct grommet there will be no problems at the firewall. But what if the car is inan accident? With the force of a good collision the wire can be easily comprimised in these areas. Now some jack-ass will probably come on and say that either they are not going to wreck or something stupid like that but I will not set myself up for failure like that.

shawn k · Post by **shawn k** » Sun Jun 27, 2010 9:12 am

If the amp has an "onboard" fuse (which is what I believed we were talking about), it would protect the amp from catching on fire just as well as one that's "within 8 inches" If there was not an on board fuse, then I would definitely say one should fuse the amp externally. If there were some sort of short inside of the amplifier (which is really the main purpose for fusing the amp anyway) the onboard fuse would blow to basically prevent a fire. The damage has already been done to the amp. Amp fuses that are onboard, or close by really don't protect an amplifier. If an amp blows a fuse strictly from drawing too much current (with nothing else going wrong) then the amp is being overdriven and the owner needs to lower the output, or upgrade to more power. Fuse location would not make a difference here.

shawn k · Post by **shawn k** » Sun Jun 27, 2010 9:13 am

ttocs wrote:under normal conditions with the correct grommet there will be no problems at the firewall. But what if the car is inan accident? With the force of a good collision the wire can be easily comprimised in these areas. Now some jack-ass will probably come on and say that either they are not going to wreck or something stupid like that but I will not set myself up for failure like that.

Good point... but I already said it

eulogious · Post by **eulogious** » Sun Jun 27, 2010 9:28 am

I don't go through the firewall. Well, at least not my own hole. I go through the fender and use the bigass factor grommet that's there for the engine bay wiring harness. Lot's of room to put wire through, and no holes to drill or grommets to install. And since it's next to the factory wiring, it's gotta be a fairly safe since the cars engineers decided to run wire there. My $.02. Oh and fuses are good

yeddy · Post by **yeddy** » Sun Jun 27, 2010 9:49 am

I was merely using the firewall hole as a most probable scenario, cuz there is a lot of people out there only drilling a hole and pushing the wire through with no grommet, I have seen this too much coming from some "pro" installers too. (cuttin corners to save a cent!) There are many other ways you could get a short. Pinched wire under a seat. Or between the door even. Hey, maybe you store your car for the winter and some rats chewed through the +wire throughout the winter. I do service work and know what people are capable of or even not capable of, I see a lot of dumb shit people do to equipment! I'm only putting my $0.02 out there cuz someone may be reading but might be afraid of putting themselves out there and asking a question.

Oh yeah and the pic I up'd from Kinetik, they should have shown a fuse between the amp and the battery, but I guess they were only showing how to hookup their equipment.

Post by **ttocs** » Sun Jun 27, 2010 10:20 am

eulogious wrote:I don't go through the firewall. Well, at least not my own hole. I go through the fender and use the bigass factor grommet that's there for the engine bay wiring harness. Lot's of room to put wire through, and no holes to drill or grommets to install. And since it's next to the factory wiring, it's gotta be a fairly safe since the cars engineers decided to run wire there. My $.02. Oh and fuses are good

I would never run a cable through the door jam. It doesn't take too much of an impact to wrinkle the fender up enough to cut through the insulation. As long as it is fused correctly you are fine but I still will drill a whole and put in a grommet before I ever went through the door jam.

eulogious · Post by **eulogious** » Sun Jun 27, 2010 10:34 am

ttocs wrote:I would never run a cable through the door jam. It doesn't take too much of an impact to wrinkle the fender up enough to cut through the insulation. As long as it is fused correctly you are fine but I still will drill a whole and put in a grommet before I ever went through the door jam.

It's about 6 - 8" from the door jam. Mine is actually through the "inner" fender, not the door jam. I agree that would be a dumb place to run a wire. I don't like drilling holes if I don't need to. Weakens the structure of the firewall, blah, blah, blah, I don't really want to get into an argument about that

Was just commenting on the lack of grommets and what I do so I always have a grommet, I just use what's already there. That's all. Proper fusing makes everything all better in the end anyways

And since he did fuse "properly" in his install, we are just hijacking this thread at this point and rambling on

But to get back on track with this thread... Are there any updates on this? Would be cool to see some updates!

gridracer · Post by **gridracer** » Sun Jun 27, 2010 10:42 am

I would never run power through a door jamb either.

dBincognito · Post by **dBincognito** » Mon Jun 28, 2010 8:16 am

If the amp has an "onboard" fuse (which is what I believed we were talking about), it would protect the amp from catching on fire

I've seen a lot of PG equipment catch fire

If an amp blows a fuse strictly from drawing too much current (with nothing else going wrong) then the amp is being overdriven and the owner needs to lower the output, or upgrade to more power. Fuse location would not make a difference here.

I was talking about getting rear ended, those fuses on or in the amp won't do shit to save the amp. They have to be externally fused within 8 inches of the amp.

shawn k · Post by **shawn k** » Mon Jun 28, 2010 10:01 am

dBincognito wrote:
If the amp has an "onboard" fuse (which is what I believed we were talking about), it would protect the amp from catching on fire

I've seen a lot of PG equipment catch fire

If an amp blows a fuse strictly from drawing too much current (with nothing else going wrong) then the amp is being overdriven and the owner needs to lower the output, or upgrade to more power. Fuse location would not make a difference here.
I was talking about getting rear ended, those fuses on or in the amp won't do shit to save the amp. They have to be externally fused within 8 inches of the amp.

The pg amps that go up in flames are due to caps leaking electrolytic fluid. The fluid is what catches fire...any fuse no matter the location will not prevent this as it take a miniscule amount of current to cause an adverse effect.

I question your knowledge of electron/current flow....the only difference between an onboard fuse and a fuse "within 8 inches" is simply 8 inches of cable...which has huge current cpability...you do reallize that an onboard fuse is placed between the terminal and the power supply!!??