The electrical system that come with the Compac is minimal but adequate for most people. There are navigation lights, a steaming light, and two lights in the cabin. All are incandescent, therefore could be a lot more efficient. We also had a compass with a small light run off the navigation light switch. This looks to be a red LED. The battery was an Exide wet cell deep cycle which looks to be a Group 27 size. This would put it at about 100 AH. The battery box is well placed in the starboard cockpit locker, as far forward as it can go. Wiring was mostly 14 gauge, with some 16 gauge. The outboard we choose has an alternator with built in regulator capable of producing up to 25A of charging. We recently sold the outboard and installed a water towed generator and a trolling motor.
Most or all of the connections were the "interlock" or snap on automotive type. When closed on the wire, these cut the insulation and press the wire into a slot. These are not suitable for marine use. The wire quality was also not the best. Unfortunately this low quality wiring is typical of small craft. Crimp connections, preferably with adhesive lined heat shrink tubing should be used. Marine grade stranded tinned copper wire should be used. Almost all of the wiring was replaced.
The deck fitting where the bow light was connected had no strain relief and was in a position where it was asking to be kicked when raising, folding, or reefing the mainsail. It didn't take long before the wire was kicked out. We didn't do any night sailing in our first season so this was not an issue except for water intrusion into the connector and the very unseamanlike appearance of the loose wire. Compac should do better.
A VHF antenna, anchor light, and windvane light were added. A new deck entry was built to accommodate the VHF antenna wire and the 5 conductor 14 gauge wire used to connect the existing steaming light, and the new anchor light and windvane light, plus two gorund wires. The windvane light was wired to the navigation light switch.
Another issue which we haven't entirely resolved is how to keep the battery charged. We have a very small 6 watt panel. The outboard had an alternator but we sold the outboard and have a trolling motor. The small solar panel proved inadequate on a 12 day sail that involved some night sailing and some use of the anchor light. The outboard was run at night occasionally to put some charge back in the battery. We now have a water towed generator which will provide all the charging we need as long as the wind holds up and keeps us moving.
Before getting a charge controller we'd run navigation lights for a few hours and then put the battery on the solar panel. We often found the battery overcharged after a day or two of charging (>14V). With just lights a radio and a few instruments as a load, we found ourselves disconnecting the solar panel often to avoid overcharging. We purchased a Flexcharge NCD25A-12 charge controller and installed it in spring 2005. We replaced the group 27 battery with a group 8D battery, going from about 100 AH to 255 AH. We plan to add a larger solar panel or two. Ideally I'd like to have two 40 watt panels in parrallel, so that if one is in a shadow we still get a good charge. If both are in the sun we'd get about 6A of charge.
With two 40 watt solar panels if we ran the trolling motor at 1/2 throttle for 30-45 minutes in order to find a mooring or good spot to anchor we'd be able to put the charge back by just leaving the boat in the sun the next day.
We've added a Navman 3100 Multi. This is a combination knotlog, depth sounder, and also provides water temperature. We have purchased a very low end fixed mount GPS. This is a Garmin 152I. It has no real chartplotter capability, it is more of a fixed mount GPS only with very minimal monochrome plotting of course relative to waypoints. The two instruments are now mounted in a teak panel on the bulkhead where previously the knotlog/depth was mounted alone.
We also have added a fixed mount VHF. Power is wired to the cabin lights. The entire VHF antenna connector assembly is brought in and out of the cabin roof when the mast is stepped and unstepped. This eliminates any connector outside the cabin which could be subject to salt water intrusion and corrosion. The VHF is an ICOM 402. We have also installed the remote "Command MIC" in the cockpit.
An inverter was added for such things as occasional use of power tools while out on the water. The inverter is a ProWatt600, capable of sustained 600 watt load but requiring more than 60 AMPs to do so, more than the current battery can provide. The inverter was mounted on the port side near the companionway stairs, where the port side berth extends aft under the cockpit seat. The inverter needs to be close to the battery and no more than 8 feet of 4 gauge wire was recommended.
We now have a rather unique installation of a trolling motor. I took a perfectly good trolling motor and sawed the shaft in two. The idea was to extend the wires and connected the two parts using 1-1/8" water hose (the diameter of the trolling motor shaft). The lower part is mounted on the swim ladder and the upper part, the control unit, is mounting on the stern rail. A fairly watertight socket intended for trolling motors is mounted in the cockpit, aft on the port side. The trolling motor is easily removed and stored in a locker. Before sawing the shaft in half it didn't fit in the locker.
A 0-16V voltmeter has been added. This is wired directly to the battery and draws its 50 mA all the time. That's 1.2 AH per day but nothing even a 6 watt solar panel can't keep up with. When the battery is well charged the flexcharge controller can be seen in action. Voltage gradually rises to a bit over 14V and then gradually drops back to 13.6 and repeats the cycle.
We also have two ammeters. There is a 10A meter for battery loads. The large loads, the inverter and trolling motor, are not wired to this meter. If we are drawing more than 10A off the lights, radio, and instruments we have a bigger problem than maxing out the meter. A 25A meter is wired to the charging sources. Two 40 watt solar panels might reach 6A and the water towed generator, though rated at 10A might reach 5-6A at best. Combined they may bring the charging ammeter to half of its full scale reading.
We also added two 12V outlets in the cabin to charge such things as handheld VHF, cell phone, or laptop. Some red LED lights were purchased to provide cockpit lighting and minimal cabin lighting for night sailing. These will be wired to the navigation light switch. The LEDs draw very minimal current and the red color should not affect night vision. One white LED utility light was purchased to see how well this works as a reading light over a berth. A few LED cabin lights have been added.
Quite a bit more detail on the eletrical changes can be found on the completed projects web page.
