Forums, Electrical Systems, Navigation and Safety equipment, Alternators and external regulators

david.barrow at 17/01/2014 16:07:33
I am hoping to take my boat to the Azores next summer for a months cruising.

I have read a lot about battery charging with all it complexities. I currently have a 13 year old Yanmar 2GM-F with a 55 amp standard alternator together with a (noisy) Air X wind generator. A few years ago I added another battery so I currently have 310 amp of storage. Whilst the current set up works pretty well I am aware that it could be improved for a much longer offshore passage. I obtained a quote for a somewhat all singing dancing system but it is far too expensive, and probably not really necessary. I could put an 80 amp alternator with the current drive belt +/_ an external regulator.

I have the average amount of electronics, a refrigerated cool box and an SSB.

I would value others thoughts and ideas .

David Barrow
Spirit of Amport

George Isted at 20/01/2014 19:53:27
Hi David,
I have the same engine/alternator + a Sterling advanced regulator so it makes the alternator kick out more amps for much longer. While a larger alternator will help reduce charging time I think there is more to be gained by making your standard alternator work harder. The only downside is that you get though alternator drive belts a bit quicker and have to keep an eye on battery water levels. Suggest you take a look at the sterling website, this is also good http://www.sterling-power.com/images/downloads/advancedcharging.pdf

Silver Harmony at 21/01/2014 14:45:30
Hi David,

your current set-up sounds perfectly adequate to me. The only recommendations I would get is to put suitable LED bulb(s) in your nav lights if you haven’t already and not rely on being able to run your cool box.

I have a 100 W Aquair towing generator which gives an average of 4 Amps on offshore passages. A 400 W Air-X should match or beat that. Since I switched to LEDs I have more electricity than I can use and could probably keep the fridge running without resorting to engine charging. That is with what I would regard as average electronics, although no radar.

With 300 Ah battery capacity you have plenty of reserve, if the Air-X packs up you can turn off the cool box and you’ll only have to run the engine for an hour a day to keep them topped up – hardly a disaster on a ~12 day(?) passage.

Have a good trip!
Robert
Silver Harmony

david.barrow at 31/01/2014 11:56:42
Thank for all the help and advice

David