Solar Panel regulator voltage, is 13.6v ok?

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Heckler

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Bought a wind genny reg off a forumite a few months ago, anyway have tested it, put a dc transformered 19v in one and and lo and behold 13.6v comes out of the other.
Question, I am going to buy a solar panel, they put out about 19v similar to the transformer, Question: is 13.6v sufficent to keep the batteries charged up during the week?
Stu
 
I suspect the current output will be more important than the voltage. If your battery is flat, milli Amps aren't going to do much to charge it. No doubt somebody with more knowledge will be along in a minute.
 
Some quite useful information on panels, controllers, etc here. I suspect that 13.6v is rather low for charging a lead-acid battery, a bit over 14 is normally quoted, but the website suggests that a controller provides according to the battery's needs. My controller keeps pumping in power until voltage reaches 14.2 or 14.3, then it starts to modulate by switching off for brief periods.
 
Did you measure the voltage open circuit or under load? If open circuit that the regulator may 'think' that the battery it is trying to charge is full as the current draw is low (non existant), so would reduce the output. Try it under load and see what the output voltage is.

If it was under load, the voltage seems low. Hopefully some one more fluent with regulator electrics will chip in and put me right - or sink my theory!
 
About the same voltage as a standard alternator regulator puts in. You'll get about 75-80% charge in the batteries.
Smart chargers put in up to 14.4 volts, over controlled periods, usually get better levels of charge into batteries.

You're grappling with two opposing theories here - a long float to compensate cells, and a sharp high-voltage top-up to bring them in line.

Both seem to work.

IMHO you can only expect wind or photovoltaic cells to slow down battery discharge. You have to rely upon shorepower charger or the engine alternator to bring the batteries up to full charge.
 
[ QUOTE ]
IMHO you can only expect wind or photovoltaic cells to slow down battery discharge. You have to rely upon shorepower charger or the engine alternator to bring the batteries up to full charge.

[/ QUOTE ]My solar panels pump 20A into my batteries and can run the watermaker by themselves. 200Ah per day from the sun is pretty typical in the Med in summer from my panels.
 
If in fact the regulator is regulating to 13.6 volts under load (on a battery) then more voltage may be in order. It is interesting that many years ago 13.6 would have been considered good but now regulators seem to be set for over 14 volts.
Much will depend on the size of your batteries and if you want all the charge you can get or just to keep batteries happy. ie if it is a small SLA battery then 13.6 might be good but if it is a huge bank and limited charging capacity then higher voltage will be better.
The voltage of the regulator can be jacked up by .7 volt by fitting a silicon diode from the negative connection of the reg to the negative battery and input wires. If you get a schotky diode this will jack it up by about .25 volts. You only need a relatively small current capacity diode. Though this is all based on a guess as to the design of regulator. good luck olewill
 
which regulator did you buy stu?

I have just added a pair of panels to my aerogen wind set up which I am pleased with, you will require blocking diodes especially if the reg is not a dedicated sun type.

I suggest some googling, I found many sites and began a couple of days reading, don't stick to marine sites as we are still a minority user of solar, many problems and fixes are out there. One thing is certain, which ever panel you buy will be wrong by someone's reckoning.. it can get a bit like anchor type threads on here.
 
Hello Jools
happy new year and fair winds, the reg is off an unknown wind turbine, havent done owt with it yet, have been busy cleaning and fettling, new boat is great BUT the maintenance regime was a bit lax, hasnt cost me owt but hard work and lots of spanner time.
Am fitting a sterling next week, only new things i bought were 2 batteries and need the sterling to wack em up good. spent the night last sunday on her, eber kept us
warm but by feck it was cold outside! other thing i found out, the eber is a d3 and it draws 3 to 4 amps, soon gets the batteries down!
Hows porthmadoc?
S
 
As others have indicated 13.6 is rather low. (I have an alternator that only manages that. It's going to the local Auto electrician when I get round to it)

BUT the reading you got open circuit may not be what you get in practice.

If it is a modern regulator with pulse width modulation I have no idea what it will do open circuit like that. If its an old shunt type then what you saw is probably what you'll get. That type will almost certainly have cooling fins as the excess is dissipated as heat. I would not have tested one as you did though for fear of the transformered DC 19volts overloading it.
 
and to you too.

out of interest, does it look anything like this one, this is the aerogen regulator..

charger_pic.jpg


13.6 is lower than mine, I will have to check but I think mine is a smidgen over 14v. They are normally adjustable.
 
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