amp power connection question

[moombadaze]

getting close to running my power wires for the amps

is it better to run the possitive directly off the battery or go to the switch?

I'd like to go directly to the battery for the main reason its a whole lot easier, and my thinking is that if the battery switch is off, the stereo switch on the dash will not turn the amps on so I really would not have to worry about battery draw

if i go this way, would the amps ever be able to draw power without the the system being on ?

thanks guys

[lewisb13]

I did negative cable to battery 1 and positive to the perko switch. The reason I personally did this is because my distribution block has a built in volt meter. If I would have gone directly to the battery the voltmeter would stay on forever.

[sandm]

fwiw, I have a dual battery setup and a blue seas acr. I added a 3rd battery wired with the deep cycle stereo battery and ran the amps straight off that battery. I went with the same theory that if the hu isn't sending power, the amps should be off. granted there might be some current draw(not sure why), but I charge them after every outing so no biggie..

same scenario on my old supra only not a acr and it was fine..

[EarmarkMarine]

Don't complicate this.
An audio system with a manual dual battery switch usually wires differently than an audio system with an ACR for good reasons. The simple version is this:
If you are using a manual dual battery switch only then use the switch as intended and go to the common output of the switch. Follow this simple instruction and you will never have the potential for a conflict.
If running an ACR without a supplmental manual switch then run the audio power directly to one of the two battery banks.

David

[MLA]

Moombadaze,

If you have a ACR/VSR and dual battery switch, then terminate the amp's B+ directly to the house battery. The stereo will only pull from the house battery bank the bank will receive charge from the alternator when engine is running.

If you only have a dual battery switch, then the ideal place to terminate the amp's B+ is to the "C" post of the switch. In this configuration, the stereo will only draw off the bank in which you have the battery switch turned to. This always leaves the other battery in reserve. The alternator will charge the bank that you have the switch turned to, or both banks if the switch is set to "BOTH".

[moombadaze]

I did negative cable to battery 1 and positive to the perko switch. The reason I personally did this is because my distribution block has a built in volt meter. If I would have gone directly to the battery the voltmeter would stay on forever.

thanks, did not think about the meter being on all the time. My distribution block has one too so i'll now being going to the switch instead.

fyi, i just have a simple battery switch from the factory

[chawk610]

Ok... getting ready to do the same. I thought each amp had to have it's own block??? So, you can run the + from the new amp directly to the common on the perko? Sorry if this has already been answered.

[MLA]

Ok... getting ready to do the same. I thought each amp had to have it's own block??? So, you can run the + from the new amp directly to the common on the perko? Sorry if this has already been answered.

In the context of a stereo, a "block" is a distribution block, which is just a junction point for multiple electrical connections to terminal. It can a fuse box, traditional audio dist block or plain old BUSS bar. All like electrical components, such as amps, will connect to the "block". The block is then connected to the battery source or switch. So, each amp doesnt require a block, but the entire system may use a block. Electrically, you can home-run each amp's B+ cable to the C post of the switch, but it gets crowded. This is one reason to use a junction point like a dist block or BUSS bar. One large cable on the C post to feed the entire system. The ground for the amps works the same, just that you do not need to fuse the grounds and the main ground will come off the battery and not the switch.

Non-fused audio distribution block http://carjamz.com/zen/images/DB701.jpg

Fused audio distribution block http://www.autotoys.com/pics/FDB9104_MANL.jpg

BUSS bar http://www.yachtsofstuff.com/adgraf/SW_BS/BS_3466.jpg

[EarmarkMarine]

Ok... getting ready to do the same. I thought each amp had to have it's own block??? So, you can run the + from the new amp directly to the common on the perko? Sorry if this has already been answered.

In many cases the answer is 'yes'. However, if you have the terminations for the helm buss, several amplifiers and the starter/alternator feed, then it can be too many stacked layers (terminal lugs) from a standpoint of the post length and too much resistance. Or, you may not have enough switch elevation to get all the cables in/out and safely isolated. There is no point in using an extra component when unnecessary but there are plenty of reasons to add a distribution block. Also, it's unlikely that you will run an amplifier directly to the switch because of the required fusing/breaker at or near the switch. If limited to two terminations you can tie two amplifiers to one post of a breaker but I would limit this and only with a breaker having 5/16" posts (eliminating any cheaper breaker with 1/4" posts).

David

[chawk610]

ok... good deal. Clear now.