Installing AM/FM/Digital media player

Hudsonian · #1 (**permalink**) 06-01-2009

I hope to replace the AM/FM/Cassette player in my boat with an AM/FM/Digital media player. When reviewing the owner’s manual prior to purchase I noted that the installation instructions call for two sources of power: one wire to an ignition or accessory circuit and another wire directly from the positive terminal on the battery. These instructions are for installing the player in a car and the wire that would come from the ignition or accessory circuit on a car will come from the switch for the AM/FM radio on the panel board on my boat and will be protected by an in-line fuse. My concern arises from the wire directly from the battery which provides power for the clock, calendar, and, perhaps, memory presets, etc. Specifically, would these loads significantly deplete the battery from which the power is to be drawn? My intuitive sense is not to worry about it; after all, the battery drain is not a problem when installed in a car. Is there any reason to think otherwise? I suppose that this wire should be protected by an in-line fuse located as close to the battery as possible.

RanAweigh · #2 (**permalink**) 06-01-2009

The third wire is to keep power to the microprocessor and memory. The system in your automobile is pretty much the same. It should draw only a few mils. It will have similar probability of depleting the battery as your automobile does if left parked for the same period of time.

camaraderie · #3 (**permalink**) 06-01-2009

Yellow is memory...red is power...If you do NOT need FM memory presets...simply wire BOTH the yellow and red to the same switched circuit breaker. The amp draw on memory is typically milliamps and if you see your boat once a month or so you should not have anything to worry about.
Some stereos feature a built in clock that is always on and these tend to draw about .2-.5 amps and can draw down much more quickly...so figure that out before you decide what you want to do.

sailingdog · #4 (**permalink**) 06-02-2009

I'd point out that some stereos will keep the memory presets without any power and only need the "memory wire" for the clock.

bruceyp · #5 (**permalink**) 06-03-2009

Funny that this came up now. I just did the same type installation on my boat. I used the wiring from the old stereo to hook up the new Stereo. It worked great until I started up the engine. With the engine running I switched on the stereo and it blew the .5 Amp fuse that was in line on the yellow wire. A friend suggested using a 1 amp fuse instead. I did this and it solved the problem. Is this a good idea? The new installation instructions didn't even mention putting in a fuse on this wire.
Anyone care to comment?
Bruce

SecondWindNC · #6 (**permalink**) 06-03-2009

cam's post pretty much covers it.

Unless you really feel like you want the station presets and other functions that require the constant source of power, just wire both to the circuit breaker. Since it sounds like you're interested in using digital media anyway, my guess is the station presets aren't that big a deal.

hellosailor · #7 (**permalink**) 06-03-2009

"blew the .5 Amp fuse that was in line on the yellow wire. A friend suggested using a 1 amp fuse instead. I did this and it solved the problem. Is this a good idea? "
In a word, no.
Either something was set up wrong in the installation, or the maker screwed up in shipping a 1/2A fuse. If the problem is the installation, you'd want to know what that is and fix it properly. If the problem is the maker...You'd still want to know if you can trust the radio not to catch fire sometime from another problem.
Sometimes, some very rare times, fuses are defective and they simply blow. The vast majority of the time, they blow because something is WRONG and putting a penny in the fusebox (or a higher rated fuse) is simply a good way to make the wire it was protecting overload and catch fire.
Odds are you can get away with it, but do you want to play the odds at all?

camaraderie · #8 (**permalink**) 06-03-2009

Quote:

Originally Posted by bruceyp

Funny that this came up now. I just did the same type installation on my boat. I used the wiring from the old stereo to hook up the new Stereo. It worked great until I started up the engine. With the engine running I switched on the stereo and it blew the .5 Amp fuse that was in line on the yellow wire. A friend suggested using a 1 amp fuse instead. I did this and it solved the problem. Is this a good idea? The new installation instructions didn't even mention putting in a fuse on this wire.
Anyone care to comment?
Bruce

Bruce...what make and model is your new stereo? Is the fuse that blew one from your old stereo or the one that came on your new one? Is the RED wire on your new one fused out of the box or are you using the old red wire? If the red wire on your new stereo was fused...what is the amp rating of the fuse? Generally you are gonna need a 5amp or 10amp (depending on the radio) fuse on either the red or yellow depending on how they are used by the partiuclar manufacturer. In the meantime...the 1amp replacement fuse should not hurt anything as LONG AS the yellow wire with the fuse on it is from the old radio.

bruceyp · #9 (**permalink**) 06-04-2009

Cam,
The Stereo is a DUAL MXCP66 AM/FM/USB CD Stereo from West Marine. The fuse that blew was from the old stereo. The new one did not call for any fuse on the Yellow wire. There is a 10 Amp fuse in the back of the new stereo. Since it is part of the stereo I have no way of knowing which wire it is fused to. The old stereo had a fusebox that had both the red and black wires coming from it. Rather than take that off I ran my new wires to those so I have an extra fusebox that wasn't called for but I don't know what size fuse that is.
From this message you can tell that Electricity is not one of my strong suits, so I appreciate the help.
Bruce

camaraderie · #10 (**permalink**) 06-04-2009

OK Bruce...that is easy. Both yellow and red are protected already by the unit. You may still wish to use fuses closer to the battery on BOTH wires as a fuse ON the unit is not the best fire prevention. If you choose to add fuses they should BOTH be rated at 10 amps.
I would reiterate...this is YOUR choice. The unit is already protected. I would get rid of the 1amp fuse in any case.
The blue wire should be taped off and not used.
Note that the yellow will put a full time drain on your battery if you wire it direct. It is a very small current used to keep your stations in memory. If you do not want that drain....wire the yellow to the switch where you have the red and forget about station memory.

Enjoy.