Another Echo Charger Question - Outboard Alternator

Sep 11, 2010
26
Oday 25 Living in Edmonton, Boat moored at Gull Lake.
Greetings. I have a 25' O'day with 110w Solar panel connected to 2 120Ahr house batteries. I would like to hook up an echocharger to charge my start battery.

I know the echo charger instructions say to connect all charging sources to the house bank, but, my motor is a 15hp electric start Johnson outboard with an alternator. I can't really hook this charging source up to the house bank.

My question is, do I need to install a switch, that would essentially turn off the echo charger when the outboard is running? The alternator on the motor does not put out a whole lotta amps, I think less than 1 at idle and maybe up to 3 when throttled.

Thank you in advance!

Mark
 
Last edited:
Feb 6, 1998
11,709
Canadian Sailcraft 36T Casco Bay, ME
Greetings. I have a 25' O'day with 110w Solar panel connected to 2 120Ahr house batteries. I would like to hook up an echocharger to charge my start battery.

I know the echo charger instructions say to connect all charging sources to the house bank, but, my motor is a 15hp electric start Johnson outboard with an alternator. I can't really hook this charging source up to the house bank.

My question is, do I need to install a switch, that would essentially turn off the echo charger when the outboard is running? The alternator on the motor does not put out a whole lotta amps, I think less than 1 at idle and maybe up to 3 when throttled.

Thank you in advance!

Mark
Your outboard takes next to nothing to start even the inrush will likely be under 100A. I know a 10HP Honda does not even break 100A in-rush.

I would consider doing everything off your house bank, house and starting, and keep your "start" battery as a "reserve" battery. This would allow you to run everything to the house bank. Depending upon the size of your solar array I would likely advise against an Echo as they draw more current than they need to off a small array.

A device like the Sterling ProLatch R would be a good option to automate charging the "start/reserve".. Most often, depending upon the age and health of the owner, I recommend a single battery bank because the motor can be pull started.

A single larger bank allows the battery to see less "use" or cycling depth and it will thus last longer.. Of course if you already have two existing banks I would not advise combining them into one now. But next time you replace the batteries this would be a good option..
 
Dec 2, 2003
1,637
Hunter 376 Warsash, England --
Why not fit the echo charger as planned and then just connect your outboard charger across the main house bank? This way the engine start battery will take what it needs from the house bank and the outboard will charge the main bank. As Main Sail has pointed out the outboard starter will draw very little power - unless it is difficult to start - and the output from the outboard will not be wasted.
It won't be much but better than nothing and unlikely to overcharge the bank unless you run the engine for very long periods.
I presume you already have a controller for the solar panels so you could feed the outboard into that.
 
Sep 11, 2010
26
Oday 25 Living in Edmonton, Boat moored at Gull Lake.
Your outboard takes next to nothing to start even the inrush will likely be under 100A. I know a 10HP Honda does not even break 100A in-rush.

I would consider doing everything off your house bank, house and starting, and keep your "start" battery as a "reserve" battery. This would allow you to run everything to the house bank. Depending upon the size of your solar array I would likely advise against an Echo as they draw more current than they need to off a small array.

A device like the Sterling ProLatch R would be a good option to automate charging the "start/reserve".. Most often, depending upon the age and health of the owner, I recommend a single battery bank because the motor can be pull started.

A single larger bank allows the battery to see less "use" or cycling depth and it will thus last longer.. Of course if you already have two existing banks I would not advise combining them into one now. But next time you replace the batteries this would be a good option..
Thanks Maine. I will definately take a look at the ProLatch R. Some further info - The two house batteries are two years old. I bought a new Start Battery, as I was unsure about the draw from the motor. I have a lot of electronics on board - 2 TVs, 2 Computers, refer, stereo, pressure water, chartplotter, depth, fish, vhf, 7 12v sockets, and a lot of lights.. I didn't want to take the chance the starting of the engine would mess with anything sensitive.

My solar panel is 120 watts, I live in Northern Alberta Canada and we get a lot of sun in the summer (almost north enough to be in the Land of the Midnight Sun). Sun is up at 5am, down at 11:30 pm.

I do spend long periods of time on the boat at the lake. I basically work from the boat. No dockside A/C.

I suppose I could probably return my start battery and add a 3rd house battery and run everything off house then, but then I'd have 2 - 2 year olds and a new one - not so good if what I read is correct!

Mark
 
Sep 11, 2010
26
Oday 25 Living in Edmonton, Boat moored at Gull Lake.
Why not fit the echo charger as planned and then just connect your outboard charger across the main house bank? This way the engine start battery will take what it needs from the house bank and the outboard will charge the main bank. As Main Sail has pointed out the outboard starter will draw very little power - unless it is difficult to start - and the output from the outboard will not be wasted.
It won't be much but better than nothing and unlikely to overcharge the bank unless you run the engine for very long periods.
I presume you already have a controller for the solar panels so you could feed the outboard into that.
The cables that start the engine are the same cables that feed the battery from the alternator. So I can't hook them up separate! I wish!

Mark
 
Dec 2, 2003
1,637
Hunter 376 Warsash, England --
If the outboard has a conventional starter (not a Dynastart) then it should be possible to separate the +ve starter wire from the +ve alternator wire inside the motor cowling.