Four sources of power

winsbury

winsbury

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I currently have a single 130AH calcium battery connected to a PWM solar panel charge controller. The feed into the charge controller comes from three sources - outboard alternator, 40W solar panel and a wind generator, each of these is combined via its own high schottky power diode mounted on a heatsink before connecting to the input of the controller. I want to add a mains powered battery charger because by the end of last weekend the battery was exhausted with no way to charge it: wind had dropped to negligible, the sun had gone down and running the outboard to recharge for several hours overnight wasn't appropriate in the marina !

No problem I thought, I had a CTEK charger in the car but its only rated to 90AH but I figured it would just take longer than ideal to charge. However it would not detect the battery and start charging at all. At first I thought it might be the solar controller interfering in some way with sensing but even disconnecting this didnt make any difference. The CTEK is back home now and working fine on a 85AH battery so presumably it cant deal with the larger capacity battery.

So, I will need to invest in a proper charger capable of the higher capacity - I think the Sterling ProSport 5/5 (2x5A or 1x10A into 12v) looks like it will do the trick but where is the best place to connect it ? I'm intending connecting it directly to the battery but does the solar charger need disconnecting when the ProSport is turned on ?
 
winsbury said:
I currently have a single 130AH calcium battery connected to a PWM solar panel charge controller. The feed into the charge controller comes from three sources - outboard alternator, 40W solar panel and a wind generator, each of these is combined via its own high schottky power diode mounted on a heatsink before connecting to the input of the controller. I want to add a mains powered battery charger because by the end of last weekend the battery was exhausted with no way to charge it: wind had dropped to negligible, the sun had gone down and running the outboard to recharge for several hours overnight wasn't appropriate in the marina !

No problem I thought, I had a CTEK charger in the car but its only rated to 90AH but I figured it would just take longer than ideal to charge. However it would not detect the battery and start charging at all. At first I thought it might be the solar controller interfering in some way with sensing but even disconnecting this didnt make any difference. The CTEK is back home now and working fine on a 85AH battery so presumably it cant deal with the larger capacity battery.

So, I will need to invest in a proper charger capable of the higher capacity - I think the Sterling ProSport 5/5 (2x5A or 1x10A into 12v) looks like it will do the trick but where is the best place to connect it ? I'm intending connecting it directly to the battery but does the solar charger need disconnecting when the ProSport is turned on ?
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You should connect the battery charger directly to the battery, not via the solar controller. The solar controller can remain connected.

Surprised you are connecting the outboard via the solar controller... Are you sure this is right or necessary?



A Ctek M300, or even a M200, will be will be adequate if you want to stick with Ctek chargers. They can deliver 25 amps or 15 amps max respectively
 
VicS said:
Surprised you are connecting the outboard via the solar controller... Are you sure this is right or necessary?
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It depends on the outboard. If it provides a regulated output then there is no point in putting that through another regulator. However, if it just gives a rectified "raw" output then it is probably worth putting that through a regulator.
 
The outboard is just an 8HP Mariner with a simple bridge rectified output at about 7amps, so the volts are very dependent on the revs and its output goes well over nominal charging voltages at high revs so figured it wouldn't hurt to have it go through the solar charger so that the battery is managed as tightly as reasonably possible from all sources.
 
You're right. When I had one of those engines it overcharged the battery as it was putting 16 volts in. FWIW I took it up with the importer (the engine was a "Sailpro" and it really should have been able to charge the battery properly). They gave me a regulator.

You'll be lucky to get 7 amps out of it though. 6 amps at most. 1 amp is a lot when you're trying to keep a battery topped up! :D

I'm not sure that you need all those shottky diodes though. Won't the one on the outboard circuit simply duplicate the rectifier in the engine....and add a further voltage drop?

What regulator are you using?
 
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I've been looking at getting a lower rated one of those for my solar panel. Are you happy with it?

They have a low power disconnect mode to prevent a battery from being over discharged. Maybe that was activated when your battery ran down?

You didn't answer VicS when he rightly said the charger should not be connected via the regulator. From your initial posting it wasn't clear how you had connected it.
 
I had tried the charger connected directly to the battery in parallel to the solar charger ( ie NOT through the solar charger ) but then because it didn't work I tried disconnecting the solar charger and connecting the mains charger direct to the battery but had the same problem. I can only imagine there's something in the CTEK car battery charger that detected the battery type wasn't appropriate and prevented it attempting to charge. Ive just placed an order for a CTEK M200 so hopefully that will work !

The low power disconnect mode you refer to is relevant only if you connect the load to the red&yellow leads, I chose not to do this as there was the possibility of having everything power down unexpectedly while on a passage and I would rather chose manually which things to power off to preserve power. In my case the boat electrics are wired directly off the battery as per normal. There is a neat timer function which one could potentially use to connect an anchor light to that would turn on/ off automatically at dusk / dawn assuming of course you only have a solar cell powering it ( in my case, the wind generator feed prevents me using this feature. )

The solar charger appears to be well made although is accompanied by the typically atrocious Chinese to English translation in the manual which take a bit of deciphering but once its set up it seems to do the trick. The only bugbear for me was that the leads are not particularly long and they are not user replaceable presumably to keep it watertight.
 
Small Ctek chargers are programmed to ignore any battery that is dead.

The trick is to connect another decent battery in parallel, and clip the Ctek to opposite ends of the 'new' double battery. The joint voltage will read above the minimum the Ctek requires, and it will start to operate. After about 20 minutes, disconnect the double battery, and fasten the Ctek to the formerly dead battery. Works for me :)
 
Thats certainly worth a try assuming of course that the solar controller doesn't have a similar cut off point... I think I still want to have a proper boat charger on board though, the M series chargers specifically talk about very deep discharge situations that are not uncommon on boats so fingers crossed this will be the right medicine.
 
winsbury said:
The solar charger appears to be well made although is accompanied by the typically atrocious Chinese to English translation in the manual which take a bit of deciphering but once its set up it seems to do the trick. The only bugbear for me was that the leads are not particularly long and they are not user replaceable presumably to keep it watertight.
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Thanks for that. If I do get one I'll remember to get a suitable terminal block as well.

You're right about my engine. "Sailmate", not "sailpro".
 
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