Sunspot 15-instruments for sailing with no battery

[christine]

I have a Sunspot 15, which has no electrical system as yet. The boat draws 1ft 11ins. I have nav lights (sold as an emergency system) which use ordinary batteries, a handheld radio and GPS which also use standard rechargeable batteries, and now I would like an echosounder, (instrument not lead line!) - is there anything that doesn't need an onboard electrical system. Do other small sailing cruisers sail with instruments but no ship electrics? What compass, log, etc could I use? I have just bought a sailpower 4hp mariner outboard, but I don't believe I will use it enough to run a highly sophisticated system of instruments. I also have a coolbox which plugs into the car cigarette lighter, could I wire it up to use onboard at all?

I know I could sail without anything however I do want to learn/keep my hand in so that I can sail on bigger boats and know what is what, as well as being a dinghy sailor.

 

[bedouin]

Re: Sunspot 15-instruments for sailing with no bat

You have a number of options. Some of the instruments can be fitted up to run on dry-cell batteries instead of a boat battery - this certainly applies to some of the Garmin units, and I imagine to others as well. Even for models that don't have the built in capacity, it would be easy to wire up batteries to give you a 12 volt feed. The problem is that these units draw quite a bit of current, and so they would get through batteries at a reasonable rate.

A better alternative would be to use a small lead-acid battery to power all the electronics on the boat. Either permanently installed with a solar charger, or one you can carry to and from the boat and charge up at home (often sold as emergency power for cars - cost about £30-40 and can be recharged from the mains or a (running) car engine).

The coolbox will draw a lot of power from the batteries and so is not really practical unless you have good charging facilities on the boat, or carry large lead-acid batteries with you. Better to run in in the car on the way down to the boat and let it keep it as cool as possible without being plugged in.

For compasses of course a conventional magnetic compass does not require any power, and "tack-tick" (I think that's right) do a solar-power compass that does not need batteries either. You can also get mechanical logs that work by towing an impellor and also don't use power, but they are getting hard to come by, are quite expensive and are not convenient in crowded waters.

 

[Guest]

I have a friend who sails a sunspot 15 on the East Coast. He has recently fitted a NASA echosounder and I guess he's come up with some form of 'ships electrical system' to power it. If you're interested in talking to him send me an email and I'll pass the details on.
I own a Skipper 17 and have recently installed a comprehensive electrical system to power a whole range of things. If you want to know details in the hope that it might help you, then again just email me.

An Ron Beag

 

[30boat]

Incastech make a flashing led echosounder that is powered by alcaline batteries and they last for ages.

 

[colin_jones]

Both Plastimo and Fiddlers Green distributors do a hand portable depth sounder, which works really well. Costs about £100.

You could make a wooden box to take a small, combined GPS and chart plotter flush mounted into one face ( or with small plotter in fascia and gps on top) and also to house a small 12v battery such as Varta make as a burglar alarm back up.

If you incorporate a battery charging socket, you could leave the unit sealed and charge up when you are connectable to mains, or even have it so that it would be recharged from an outboard.

The ensemble can be fixed to a thwart by bungies, or by a couple of right angle bracket and thumscrews.

It is a nice winter project. Mine lasted for several years on a RIB. The electronics draw very little current, so the unit will run for plenty of hours without need to recharge.

 

[JimC]

On my Leisure 17 I used a motorcycle battery (about £25) to power the cabin light, an all-round white masthead light, a NASA target depth-sounder, the compass illumination, and a cigar lighter socket for accessories. The battery was charged by the sailpower outboard and occasionally topped-up with a mains charger. I had to fit a car-type suppressor to the alternator on the outboard to stop it interfering with the sounder and causing erratic readings. Both compass and sounder were permanently mounted on the bulkhead as in normal yacht practice. The system worked well and continues to do so 7 years on.

Good luck