Quote Originally Posted by MLA View Post
Yes, I understand is was in the boat originally, but was it protection and why is it now extra? I ask, because I do not read that an old amp was removed. My concern is that some circuit is now unprotected.

The max amperage your amps should ever pull cumulatively, is 160W based on their onboard fusing or the manufacture's spec. Its never safe, not needed, to fuse above that potential load. 200A is about 30% over rated. Now, the real problem is the focus put on circuit protection capacity, but can the cable support a 200A breaker? If not, then cable becomes the weak link and if there is a short, becomes a hot flaming molten rope of death, long before that 200W breaker might trip.

I would suggest a trunk/branch setup over individual amp supply runs. And I do not suggest automotive amp install kits. They rarely work well for boats. Buy the incidentals a-la-carte in the proper lengths and amp ratings for fuses or breakers.
Below is why I was using a 200 amp circuit breaker. I'm not saying I'm right, but this is why I was planning on using it.



philwsailz


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Stillwater, Oklahoma
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Quote Originally Posted by Hydrofoiljunky View Post
Ok, I have a couple questions. I finally got my other amplifier in so I'm ready to hook them both up. I'll be running a Kicker 700.5 and Kicker 550.2. Since my amps have fuses in them do I need to run inline fuses between the distribution block and the amps? Also, will running 4 gauge power from battery to the distribution block and then 4 gauge wire out to the two amps be alright? If not what kind/size of distribution block do you guys recommend and what kind of power wire off the battery to the block and out to the two amps? Thanks in advance.

P.S. Been trying to read up on Capacitors, do any of you guys run one? Did it help? Seems like from what I read that the first time the sub/s need that power it takes it all and then it can never catch back up making it...well pretty much useless, what do you guys think? This audio stuff is fun but man there is a lot of info Guess I should have been installing systems in my car back in high school instead of chasing women LOL


Chad
Chad-

Each amp has its own fuses, to protect the amps. You DO NOT need fuses between the distribution block and the amps. Adding extra fuses between the distribution blocks and amps only adds more individual electrical connections, increasing the chance of failed contacts, corrosion, and other problems associated with open metal-on-metal connections in a marine environment.

You DO need a fuse or a curcuit breaker on your primary power wire between your battery and your distribution blocks, right next to the battery, equal to the sum of the fuse values recommended in the amplifier's owners manuals.
The ZX700.5 has 90 amps of fuses, and the ZZX550.2 has 70 amps of fuses, so you want AT LEAST 160 amps of over-current protection right at the battery on the primary power lead going to the amp distribution blocks. A 200 amp fuse or circuit breaker will do the job, and is safe, as Coast Guard law for new boat production allows overcurrent protection up to 1.5 times the max current draw of the electrical components on the circuit. Coast Guard law also mandates that the fuse or circuit breaker have no more than 7" of wire between the battery and the fuse or breaker. For your own use, you can go further; sometimes it is impossible to really get the fuse or breaker that close to the battery, but try to be within a foot or so... The reason for providing a fuse right at the battery is to prevent an accidental short circuit of your primary power wire, resulting in a very hot hunk of copper, burning insulation and a fire or explosion on your boat.
So starting at the battery positive terminal: You have a short piece of LARGE wire, (I recomment 2 ga or 1/0 ga, NOT 4 ga as you suggested), then a fuse holder with a 200A fuse, (or a circuit breaker if you can find one that big) then you have another LARGE wire, (2 ga or 1/0 ga) going to the positive distribution block near the amps. From the positive distribution block you have 4 ga wires going to each amp.

For the negative side of the equation, us a similarly large ground wire going from the battery to a distribution block, and then 4 ga wires to the ground terminals of both amps. No fuses needed on the ground side...



There are lots of theories on capacitors, and very few facts. Some people use them with good results; I will tell you those folks probably have inadequate charging systems and insufficient amounts of copper between their batteris and their amps. The caps cover up the voltage sag that shows up as a result of poor system design like a band-aid covers up a cold sore.
Proper systems, with alternators, batteries and wiring sized properly for the system do not need caps.


I have attached a very crude schematic showing my preferred wiring method for a dual amplifier setup. It shows the relatve locations of the big fuse, the distribution blocks, and the amps. In this schematic I also show a wiring scheme that moves the radio's power out of the dash wiring, (noisy) and onto the amplifier power wiring, (lots quieter). The relay shown takes advantage of the boats accessory ignition switch position, (like in an older car, where you turn the key backwards). If you have a dash rocker switch for your stereo, you can use it instead of the relay. I have attached that pic, even though it only shows a single amp.

Anyway, if you have further questions, let us know. good luck and have fun!

Phil
Kicker