Qustion on Stay-n-charge

[sherm]

Scenerio, I have a storage facility for my boat 1 mile from the ramp. The storage has no power. I bought the 12/24 unit just to get power from the big motor since my towing is almost non existant. My question is does anyone else have this set up? Will I ever need to remove the batteries and bring home to charge, or will the big motor (115 hp) do the trick. I realize it depends on how much I run, but was curious if anone has used this without towing and never had to charge the batteries with a charger?

[-Joe-]

I have one on my 36 volt system. You basically answer your own question by it depends on how long you run the big motor. I do charge mine when I come in off the water to insure the batteries don't sit on a partially charge. I will say that running my 101lb 36 volt TM all day on 60-70% speed I have never killed my batteries by running 10 mins or so every hour (approx.)

[Buzbait88]

Not sure about your 115, but on a 150hp or bigger it will take about 10min of runtime to give you an hour of battery power on high.  So it does it reasonably fast.  Even though you're close to the ramp you can still benefit from the all charge.  It takes usually a good 20-30 min loading and unloading your boat so if you leave your truck run while you get your straps off and the rods and reels ready or leave your truck run while you are putting everything away you will have close to an hour of charge time on your unit.  The biggest benefit for me is being able to charge at the ramp.  I had a weak starting battery and if I left my GPS unit on it would run it dead.  I live close to the ramp to so the short time didn't give me quiet enough to turn the big v6 over on its own, but with the help of the stay-n-charge I could boost the big motor and get it going.

[screwballl]

Have you thought of looking into a Solar battery charger?
You can get a 5W for under $50, a 15W for around $100. Just set it out in the sun for a few hours and then come back to pack it up.

I am planning to get a small 1.8W (for $19) for my jon boat battery so it helps charge it while I am sitting there fishing.

[CatFan]

Have you thought of looking into a Solar battery charger?
You can get a 5W for under $50, a 15W for around $100. Just set it out in the sun for a few hours and then come back to pack it up.

I am planning to get a small 1.8W (for $19) for my jon boat battery so it helps charge it while I am sitting there fishing.

1.8W at the 14.7V it takes to charge a battery is 122.4 milliamps.  It would take 68 sunny days for that current to charge a battery if everything was perfect.  Everything isn't perfect and your battery loses power faster sitting there with no equipment running than that panel could ever consider recharging it.  Anything less than 50W on a single battery is a waste of money.

[CatFan]

Not sure about your 115, but on a 150hp or bigger it will take about 10min of runtime to give you an hour of battery power on high. 

Lets do a little math:  An hour of TM run time drawing mid-range 20A out of the battery consumes 20AH from the battery.  To replace that, you need to provide 40AH to the battery from the charging system since batteries waste about 50% of the charging power as heat.  To provide 40AH in 10 minutes, you have to charge at a rate of 240A.  Your outboard can't provide anything close to that, and if it could, your battery would explode long before the 10 minutes was up.

[screwballl]

1.8W at the 14.7V it takes to charge a battery is 122.4 milliamps.  It would take 68 sunny days for that current to charge a battery if everything was perfect.  Everything isn't perfect and your battery loses power faster sitting there with no equipment running than that panel could ever consider recharging it.  Anything less than 50W on a single battery is a waste of money.

I think you're expecting a fast and almost immediate charge which will damage the batteries over the long term.... normal battery chargers only charge somewhere in the 5-10A range, and "quick charge" chargers are still only in the 10-15A range. Now a model with a "starting" option may have a short 10-20 second burst at 100-300A, but those are short bursts to supplement while starting. I have a small unit that has the option for 2A, 4A or 6A. On a low car battery at 6A, it typically takes 6-8 hours to fully charge, sometimes a little longer.

1.8W as mentioned before is a trickle charger. 1.8W at 12V = 0.15A
My charger at 6A = 85W
Quick chargers 15A at 14V = 210W
This is why most battery chargers are in the 10-15A range.

Also remember that batteries hold long term charge better if charged slowly at low Wattage/Amperage. Fast charging causes excess sulfation causing an extreme shortage in the battery's life. Slow charging allows the sulfur stuck to the batteries positive plates to return to the electrolyte. Fast charging causes an imbalance by failure of enough sulfur to return to the electrolyte.

[CatFan]

I think you're expecting a fast and almost immediate charge which will damage the batteries over the long term.... normal battery chargers only charge somewhere in the 5-10W (0.3-0.8A) range, and "quick charge" chargers are still only in the 10-15W range. I have a small unit that has the option for 2W, 4W or 6W. On a low car battery at 6W, it typically takes 6-8 hours to fully charge, sometimes longer.

1.8W as mentioned before is a trickle charger. 1.8W at 12V = 0.15A
My charger at 6W = 0.5A
Quick chargers 15W at 12V = 1.25A
This is why most battery chargers are in the 10-15W (0.8-1.25A) range.

Now an alternator and the battery chargers are different animals.  Alternators are designed to charge while there is draw or to equalize the charge, yet many of them do no charging under no draw. So if you figure your boat has a 60A alternator, 100Ah/500CCA battery, at half empty, would take about half an hour or less idling to get to close to a full charge before the alternator stops charging and you are just wasting gas.

Also remember that batteries hold long term charge better if charged slowly at low Wattage/Amperage. Fast charging causes excess sulfation causing an extreme shortage in the battery's life. Slow charging allows the sulfur stuck to the batteries positive plates to return to the electrolyte. Fast charging causes an imbalance by failure of enough sulfur to return to the electrolyte.

You are confusing Amps and Watts and repeating incorrect battery myths.  Take my word for this.  I'm an electrical engineer and spent about 11 years working in battery test.

Most boat chargers are 5-15 Amps.  That's about 75-220 Watts.  Anything less than 2A won't recharge a boat sized lead-acid battery due to problems with internal resistance.  A 6W charger would never recharge any car battery.  Half of the power you apply to a battery to charge it is wasted as heat.

Your charger is 2-4-6 Amps, not Watts.

The charge rate stuff is completely bogus too.  Charge them as fast as you can.  This keeps the battery in better shape.  Charging slowly just lets the battery sulfate due to the long time before it is recharged.  The only risk with fast charging is battery damage from heat, but this usually isn't a problem below a 20A rate at normal ambient temperatures.  Battery manufacturers typically recommend their products be charged somewhere between C/8 and C/4, which is between 12.5 and 25A for a 100AH battery.

To charge a battery, you have to use an input voltage that is higher than the battery.  That means you need to be above 12.65V for a standard 12V battery.  Charging usually starts around 13.3V, but most panels are rated at 15V.  That means your 1.8W panel is providing only about 120mA at a voltage useful for battery charging, and half is wasted as heat going into the battery.  As a comparison, your panel, on a bright, sunny day, will provide about as much output power as 9 AAA batteries could for 10 hours.

A half hour of idling a boat wouldn't charge a battery at all.  Most alternators don't provide more than a few amps at idle, and that would be consumed running the ignition and alarms.  They typically kick in and begin charging around 2000RPM.  An alternator works exactly like a battery charger when it comes to charging the battery, but it can also act as source of power when there is a load applied to the circuit. 

[sherm]

So, I guess I'm stuck hauling the batteries back to the house. 

[CatFan]

So, I guess I'm stuck hauling the batteries back to the house. 

How far from the storage facility do you live?

[sherm]

The storage is on the lake 30 minutes from my house

[Stayncharge]

Sherm here is an anwer for you that you should be able to live with and not have to listen to a bunch of different people telling you what you can and can't do. Every body fishes different then each other. All the numbers in the world (not saying there numbers are wrong so don't everyone jump out of there shorts) are not going to prove true or false for how you do things. You keep using the unit for the next 60 to 90 days and if it is not doing what you want it to do then I will buy the unit back from you with no hard feelings at all. I think since your trip is over 30 minutes to the storage yard I would like for you to try the truck harness as well and see how that works for you. I am even willing to send you the truck unit for you to try for the next 90days and if between the both units they don't do what you need and I will take them back and you are not out any money at all. This way you can know for yourself and not others telling you how to fish. Let me know if I can help in any way at all. Thanks
Oh one more thing Sherm. I have been charging batteries on boats for more then eleven years now and since I have been on the market almost every on board charging company on the market today have come out with a charge on the run system that charges your trolling batteries from the outboards. Minkota,guest dual pro and others. So I guess we are all just blowing smoke.

[Buzbait88]

Sherm here is an anwer for you that you should be able to live with and not have to listen to a bunch of different people telling you what you can and can't do. Every body fishes different then each other. All the numbers in the world (not saying there numbers are wrong so don't everyone jump out of there shorts) are not going to prove true or false for how you do things. You keep using the unit for the next 60 to 90 days and if it is not doing what you want it to do then I will buy the unit back from you with no hard feelings at all. I think since your trip is over 30 minutes to the storage yard I would like for you to try the truck harness as well and see how that works for you. I am even willing to send you the truck unit for you to try for the next 90days and if between the both units they don't do what you need and I will take them back and you are not out any money at all. This way you can know for yourself and not others telling you how to fish. Let me know if I can help in any way at all. Thanks
Oh one more thing Sherm. I have been charging batteries on boats for more then eleven years now and since I have been on the market almost every on board charging company on the market today have come out with a charge on the run system that charges your trolling batteries from the outboards. Minkota,guest dual pro and others. So I guess we are all just blowing smoke.

WOW, talk about customer service!  That is awesome Jim!

[CatFan]

The storage is on the lake 30 minutes from my house

I was going to suggest hauling it home to top them off before storing them.  Probably wouldn't be convenient then.

[MaineSkeeter]

Now thats TOP NOTCH......Ask any other manufacturer to do that and see what they say.  Quite possibly there might be a Stay'N'Charge in my future!!!!!!!!!

[screwballl]

My apologies, my mind was on Watts instead of Amps on my above post, since I saw the solar chargers specs showing 1 and 1.8W and associated that with my charger which is 2A, 4A and 6A... I will edit it...

[screwballl]

The charge rate stuff is completely bogus too.  Charge them as fast as you can.  This keeps the battery in better shape. 

That is completely wrong with most modern batteries.

Most manufactures state something along these lines:

The higher amps necessary for rapid charge heats up the battery, which shortens battery life. It also causes more gas to form in the liquid (acid) in the battery. This gas is hydrogen, and is highly explosive. Hydrogen gas can build up enough pressure to swell or explode the battery, which is extremely dangerous. Acid can spew all over the place and cause bad burns. To avoid this, the six cell-caps on top of the battery have vents in them to let the gas out, but rapid rates of charge may produce more gas than the vents can cope with. Thus it is much safer to unscrew or lever off the caps(depending on the type of battery), and set them loosely over the holes. This lets the pressure out, but keeps debris from falling into the interior of the battery.

Secondly, and equally important, you must avoid open flames or sparks, which might ignite the hydrogen gas. In an enclosed space, turning on an electric light or switch can be enough to cause an explosion . Charging the battery outdoors is safer than indoors, but if the garage door is left open to provide good air flow, it is fairly safe.

In conclusion, the slower 2-4amp rate of charge is easier on the battery and safer for yourself, but takes overnight. The rapid rate (10-15amp) is fairly safe if suitable safety precautions are taken.

Sherm, I was reading up on the main StayNCharge system. It runs in 2 minute cycles: on/charges for 2 minutes, off for 2 minutes, but from what I am reading this is still forcing a high amperage charge into the batteries. It just tricks the alternator on the running outboard into thinking there is a draw and forces it to kick in and charge for those 2 minutes. After that it goes back to normal and the alternators will work like usual those 2 off minutes.
I am cautious about their claims though, if it is on for 2/off for 2, and it says for every hour you troll on high, it will take 10 minutes to bring a 24volt system back to full, well that is three separate 2 minute cycles, and if it claims full charge, that has to be grabbing full amperage (60-120A) from the alternator on the outboard. So that means for every hour you run your trolling motor, you need to run your outboard (and not at idle) at least 10 minutes to recharge the batteries. If you are on an electric only lake, this is not possible. Also just idling the outboard will not give the alternator enough juice to allow for proper charging with or without this system, so you will need to kick the RPMs up to get enough juice for this to work properly. At idle, the alternator tends to produce 13.8 to 14.2 volts at idle with the lights and accessories off, this is on par with most low Amperage trickle chargers. For heavy charging, maximum output 14.7V or higher is typically achieved at or above 2,500 RPM.

[Stayncharge]

OK guys all your numbers are great for what you want to do but the question that was asked was about a certain product and it has nothing at all to do with all these numbers that are published by AC chargers so please either answer the mans question or please move on. Thanks.

[screwballl]

OK guys all your numbers are great for what you want to do but the question that was asked was about a certain product and it has nothing at all to do with all these numbers that are published by AC chargers so please either answer the mans question or please move on. Thanks.

Thanks for stopping by and willing to work with the original poster.

What I mentioned in my last post is still a valid question.

The original poster stated he has a 115hp motor, and those motors on average tend to come with a 60A alternator.
Depending on the trolling motor he has, it can vary from 40-60Ah.
I am not sure about the battery setup but lets say around 110Ah battery.
This means the 60A alternator on the outboard running around 2000-2500 RPM for 30-45 minutes should charge the battery most of the way.

If the stay-n-charge system (for the boat motor system, not the trailer system) is on for 2 minutes and off for 2 minutes, and claims to charge that 40A in approximately 10 minutes, does that mean it is forcing 240A at a time for 2 minutes? but if the alternator only puts out 60A, how is your system able to ramp that 60A up to 200+ Amps over short term without adding a second high output alternator? Or am I looking at this the wrong way? Is it just like I said earlier, it is tricking the alternator into a full draw state forcing it to kick in and draw its full 60A for those 2 minutes at a time?

[-Joe-]

An alternator is only going to charge whats in its capibilities. Once the cranking battery has reached its charge the stay-in-charge simply sends the charging voltage to the TM batteries. You are not and can not send 240 amps from a 60 amp alternator. Once the batteries reach full charge the alternator will quit charging regardless if the SnC keeps switching or not. The voltage regulator will prevent the alternator from over charging a battery once it reaches peak charge.

[tsmith35]

You keep using the unit for the next 60 to 90 days and if it is not doing what you want it to do then I will buy the unit back from you with no hard feelings at all. I think since your trip is over 30 minutes to the storage yard I would like for you to try the truck harness as well and see how that works for you. I am even willing to send you the truck unit for you to try for the next 90days and if between the both units they don't do what you need and I will take them back and you are not out any money at all. This way you can know for yourself and not others telling you how to fish. Let me know if I can help in any way at all. Thanks

Wow, now THAT'S customer service! I'm impressed.

[sherm]

An alternator is only going to charge whats in its capibilities. Once the cranking battery has reached its charge the stay-in-charge simply sends the charging voltage to the TM batteries. You are not and can not send 240 amps from a 60 amp alternator. Once the batteries reach full charge the alternator will quit charging regardless if the SnC keeps switching or not. The voltage regulator will prevent the alternator from over charging a battery once it reaches peak charge.

The way I understand it, it's not off for 2 minutes it switches to the 2nd battery for 2 minutes.

[-Joe-]

The way I understand it, it's not off for 2 minutes it switches to the 2nd battery for 2 minutes.

That is correct, What mine does, as long as the cranking battery is full it sends the charging voltage to the TM batteries and rotates between them (3 in my case) as long as the big motor is running. If the cranking battery ever drops below 13V then the SnC will drop out and allow the cranking battery to charge. Once its full, it goes back to rotating between the TM Batteries.

[screwballl]

So then their claim of fully charging the battery in 10 minutes (which may equal either 4 or 6 minutes charging time) is an exaggeration... I figured.

[sherm]

So then their claim of fully charging the battery in 10 minutes (which may equal either 4 or 6 minutes charging time) is an exaggeration... I figured.

WOW, Why would you slam a product before you try it?

I heard 10 minutes of charging would provide 1 hr of trolling. Jim is good enough to offer to send me the tow package, When I get it and install it I'll report how it works ! I'm looking forward to it.