Fuse Sizing and AMP Selection

[Twrandall]

I've got an '03 AN 216 with 6 inboat speakers, 2 Rev 8s and a sub. I've got a Wetsounds HT6 (110X6) powering the inboat speakers, a Wetsounds HT4 bridged (300x2) running the Rev 8s and an Alpine (300x1) running the sub. I've got 1/0 running from my perko switch and starter battery (where my 2nd battery negative is tied into) to a distribution block. Then the amps have 4GA from the distribution blocks. I also have a Wetsounds 420SQ tied in the mix. I want to redo how and where everything is mounted and can't fit the HT4 and Alpine in the space I want to put the amps and distribution blocks. So my thought is off the HT4 and Alpine amps and get another HT6 to run the sub and Rev 8s since power (RMS) would be the same.

Wetsounds website says max current rating is 60A for the HT6 but if I plug the numbers (600W and 900W max) into http://www.bcae1.com/images/swfs/sys...assistant2.swf it tells me to use a 60A and 90A fuse to protect them so now I am confused. I also want to tie a marine circuit breaker into the 1/0 vs an ANL fuse because of where it is located in my battery compartment and the potential of getting wet from people walking around the boat. 1/0 is rated for like 300+ amps but clearly I don't need that because of what is down stream.

So my questions ...

1) any reason I wouldn't want to combine my tower speakers and sub on a single HT6 amp?
2) what size fuses do I need to protect the inboat HT6 (660W at peak) and Rev8/Sub HT6 (900W at peak bridged)?
3) what size fuse/circuit breaker should I run on the 1/0?

[nyryan2001]

randall - my 2 cents:

1. no, lots of money for that swap though.

2. 80A is what I would do. a little higher than whats exactly spec'd so when running it hard you dont blow a fuse from a small varience. The HT6 has internal fusing to protect it. Your job is to supply a big (safe) straw to suck power.

3. roughly 200A is my guess. likely you are already tapping in at the fuse panel? is that already fused also? Dont be fooled, that 200a fuse will pop in a milisecond when grounded out, even if you were only using 8ga wire.

Would be best to confirm your exact plan with guys like David and MLA.

[EarmarkMarine]

There is always a way to create a second and smaller amp panel. I like what you have now. If you are running an HT-6 bridged into three channels with a 4-ohm load on all channels that is effectively a 2-ohm load on all six channels, plus, the tower and subwoofers are the two most demanding zones. So I prefer to keep these broken into two amplifier chassis unless it is an amplifier with dual internal power supplies.

To fuse the individual amplifiers after the trunk line division follow the manufacturer fusing as close as possible. No lower. And no higher than what the closest fusing or breaker is available. Music is AC so a DC equation isn’t going to apply with any degree of accuracy. Fusing is not usually related to operational usage but for protection in case of a major internal failure. The amperage draw will exceed the fuse size rating for a time period before the fuse will burn.

At the power source, add up the collective individual fuses and use a value closest to that, again, based on what is available. A value just barely under the collective will not blow. This particular fuse or breaker is intended to protect the boat and occupants in case of an accident which could create a short. A 0-gauge will otherwise catch everything around it on fire before it burns through.


Odin

[Twrandall]

So I've been playing around with Visio and really can't make the Alpine work so I think I am going to hook up an HT1 to match the other Wetsounds and mount them with the wires running behind the board so stuff isn't exposed to catch on something. So on the 1/0 if I add everything up I get up to 160 amps so would I be good with just a 150 amp marine breaker or should i up size to the 200 amp?

[EarmarkMarine]

You should be fine with a 150A breaker, that's only about 6% under the total rated amperage, and the odds of you ever approaching 150A current draw are slim to none.