Adding a New Compact-Disc Player

not all) are of the centrifugal type, and correct impeller rotation is imperative if the pump is to work properly.

A new CD player, like any other electronic equipment you decide to install or add to your boat’s inventory of goodies, is a prime example of equipment that is polarity sensitive. Essentially, motors and any equipment that contains any type of solidstate circuitry all fall into this category. It pays to be quite cautious here, as mixing the positive and negative conductors can burn out internal components of valuable equipment quicker than you can snap your fingers.

Having said that, the rest of the installation of a CD player is relatively easy, especially if you have found the above descriptions of the installation of the cabin light and bilge pump easy to understand.

Really, the most difficult part of installing a CD player is figuring out where you want to mount it and cutting the hole in the panel for the face plate. Some electronic equipment today will have a heat sink mounted on the back chassis, as shown in figure 9-8. This heat sink does just what the name implies; it radiates heat away from the parts within the equipment it’s designed to protect. Make sure that the airflow past this heat sink is adequate to provide necessary cooling when the equipment is in use. Proper cooling of the equipment will improve its longevity and performance. How much cooling air is enough? Not much; just don’t stuff your valuable CD player into a tiny hole with no room for air to circulate.

Once you decide on a good location for your new CD player and cut the necessary mounting holes, you’re ready to wire it in. I’m sure you remembered to check the packaging before you left the store after buying the player. Quite often the installation instructions include a template for the mounting cutout. Having this template will save a lot of time and ensure that you get a proper installation with a minimum of fitting.

As with any electrical equipment, always follow the fuse recommendations provided by the manufacturer. Most CD players come with a two-wire harness about 18 to 24 inches long with an in-line fuse holder already installed on the power lead. Typically, these leads are made with 16 AWG wire. Since most such equipment (but not all) draws less than about 1.5 amps, 16 AWG is usually large enough for runs of up to 30 feet (where the CD player is located 15 feet away from the power source). If the distance from the power goes over 15 feet, step up to 14 AWG.

In this example, using the 3 percent voltage drop from chapter 4 for a circuit length of 30 feet, 1.5 amps falls below the 5-amp minimum column in figure 4-3 on page 44. Remember to always round up in wire size and use the 5-amp column calling for a 12 AWG wire for a 30-foot run. As soon as you move over to the 40-foot column, the table calls for 10 AWG wire. If the run were, say, 32 feet I would stick to the 12 AWG, because you have already rounded up once.

Also, remember that safety-related electronic equipment will always fall into the 3 percent voltagedrop category for wire sizing. Much of this equipment (particularly fish-finders, but other gear as well) is designed to work in a fairly narrow voltage range. (See chapter 12 for more details on this subject.)

Your new CD player should be tied into your main distribution panel just like the cabin light already discussed. Since it falls into the generalequipment category, the use of duplex wire with red and black or red and yellow wires will keep the feed

Fig. 9-8. Typical electronic equipment heat sink.

wire in compliance with the ABYC’s color-coding scheme.

A 10-amp circuit breaker or fuse at the panel will be a good choice here as long as the manufacturersupplied fuse and holder are not removed from the circuit. Remember that the panel fuse will protect the wiring to the CD player, and in the case of 16 AWG wire, the basic ampacity for 105°C-rated wire (the most common) is 25 amps, so a main breaker rated at 10 amps is safe and, in fact, conservative.

Since the factory-supplied harness that came with the CD player probably came with quick-disconnect bullet-type connectors, you can use the same type to splice into the harness you’re running from the panel to the player. These bullet-type connectors come in male and female halves, and are a good way to ensure that the polarity of the equipment is observed. Just make sure the correct connector ends up on the appropriate wire.

Many installers cut off these bullet connectors and replace them with straight butt-type crimp connectors, feeling that these might be less likely to corrode. The truth is that this is not such a great idea, for several reasons. First, the standard male and female bullet connectors enable a quick disconnect in the event you need to remove the CD player for service or whatever reason, and the connector can be reused when you reinstall it. Second, most bullet connectors that I’ve seen have a rubber seal to minimize water intrusion. Last, these connectors are a good way to ensure that polarity is observed, regardless of wiring color.

Figure 9-9shows the bullet-type plug connector in question.

For the installation of the wire for your new CD player, follow the same ten steps for installing the cabin light, and you’ll be ready to go with the main wiring for the player. (Review the Step-by-Step Instructions earlier in this chapter.)

Keep in mind that many pieces of electronic equipment today will have two positive feed wires, one switched and the other intended to supply a constant DC current. This is to maintain any internal memory the equipment may have for such things as preselected radio stations. So when selecting your power for the memory function on your player (if needed—check your owner’s manual), remember that this connection must be live at all times, and probably the best source of power will be at the feed side of your main battery switch or at the battery itself.

Fig. 9-9. Typical “bullet-type” electrical connectors. These are useful if installed as opposites on the positive and negative return wires in preventing a reverse-polarity situation that can damage sensitive electronic equipment.

Adding Speakers

When it’s time to connect the speakers for your newly installed CD player, regular speaker wire, available from Radio Shack and other stereo-supply houses, will do the job. However, because of the better insulation, a better choice would be the marinegrade duplex wire already mentioned.

The ABYC doesn’t address speaker wires in its color-coding scheme, so select duplex wires with different color schemes to help identify left and right speaker leads. When running these leads, remember to observe polarity, and don’t mix up the wires. As with any wiring on board, speaker wires should be supported at least every 18 inches.

Once wire gauge and circuit protection decisions have been made, the six-step list that follows will guide you through the installation of the CD player and speakers. Remember that when locating the speakers, the magnets contained within them will affect things like compasses and any electronic compass sensors you may have on board. Keep the speakers at least 16–18 inches away from compasses and sensors!

1. Use the cutout template supplied with the player and speakers to cut out your mounting holes. 2. Install your speakers and the player in the holes. 3. Route all wiring from power sources, ground connections, and any speaker or antenna leads. Be sure to secure the wiring and provide chafe protection where needed, as described in chapter 4. 4. Connect all wires to the back of the player and to the speakers, carefully following the printed instructions supplied with the equipment as to which wire goes where. 5. Test the operation of the equipment. In other words, turn it on and see if it works. 6. Finish mounting the equipment chassis in the mounting hole. Enjoy!

Figure 9-10provides a wiring diagram for this installation that includes the speaker wiring.

If you keep the points mentioned here in mind for all of your DC circuit additions and carefully follow the steps outlined, including the tables and charts in chapter 4, you should have no problem adding your own equipment to your boat in a safe and professional manner.

Left Speaker Right Speaker

CD Player

Fig. 9-10. Basic wiring diagram for a new CD player.