gift
Companion Planting Guide by World Permaculture Association
will be released to subscribers in: soon!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
permaculture forums growies critters building homesteading energy monies kitchen purity ungarbage community wilderness fiber arts art permaculture artisans regional education skip experiences global resources cider press projects digital market permies.com pie forums private forums all forums
this forum made possible by our volunteer staff, including ...
master stewards:
  • Nancy Reading
  • Carla Burke
  • r ranson
  • John F Dean
  • paul wheaton
  • Pearl Sutton
stewards:
  • Jay Angler
  • Liv Smith
  • Leigh Tate
master gardeners:
  • Christopher Weeks
  • Timothy Norton
gardeners:
  • thomas rubino
  • Jeremy VanGelder
  • Maieshe Ljin

Ignorance aint so blissfull! (Solar Dummy on the loose!)

 
Posts: 221
31
  • Likes 2
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
OK its a lousy and non descriptive title!

I have a coupla cheap solar charge controllers, both of them tell me that the input is for photoelectric input only, and specifically say not to hook them to a generator.

Why?

Is it to protect them from over voltage, over current, or just boilerplate?

In specific I want to put one between a tow vehicle and a battery bank to provide a three stage charging profile, is this a nonsense application and I should just depend on the tow vehicles voltage regulator (standard Chrysler electronic regulator) ?
Do the two regulators mess with one another and provide inaccurate results?
Does a  blocking diode between the battery bank and the tow vehicle block the vehicle system from reading the battery state?

Hoping for answers prior to gambling $13.00 (US!) on a smoke test!
 
master steward
Posts: 6973
Location: southern Illinois, USA
2538
goat cat dog chicken composting toilet food preservation pig bee solar wood heat homestead
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I do have solar, but I dont have the answer. I suspect the only one that does is the manufacturer. But, there are people on this site with more knowledge than me, so let's wait for more answers.
 
gardener
Posts: 2514
Location: Ladakh, Indian Himalayas at 10,500 feet, zone 5
838
trees food preservation solar greening the desert
  • Likes 2
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I've never learned enough of the technical stuff, but I've lived in an off-grid solar powered school for over 20 years. A generator would produce AC power of 110V or 220V depending on your country. Solar panels would produce DC output, and the inverter will say which voltage it takes, probably 12, 24 or 48V. Very very different. Attaching a source of one type into equipment designed for the other will probably burn out the equipment. I would fear that it could possibly start a fire or at least some exciting sparks.

Even if the generator can produce DC power of the required voltage, I'm not sure, but solar charge controllers may be meant to deal with a comparatively low amount of power coming in, and the generator might be producing much more amps, or whatever it is. I don't know if that would make a difference or wear out the equipment.
 
Posts: 16
Location: Pitesti, Romania
3
trees bee homestead
  • Likes 1
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
You have DC there (yes, the generator produces AC but in a car you also have a bridge rectifier/voltage regulator as your car systems work on 12V DC).
In theory you can put what you want but you need to see what the current draw will be. There are smart charge controllers that let you limit the drawn current.
 
pollinator
Posts: 920
Location: Central Ontario
171
kids dog books chicken earthworks cooking solar wood heat woodworking homestead
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
They do make charge controllers for that purpose. Search a 12 volt dc to 12 volt dc charger. Your cheap pwm controller may or may not burn out if you use it as described there are just too many on the market to tell...
 
Posts: 34
7
  • Likes 1
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi Bill,

Most of the answers are already given, and are fine.

Here is just my 2 cent on it:

The input of a solar charge controller is designed to suck the most current (wattage to be precise) as possible out of the solar panel. (PWM or MPPT based charge controllers).
So even if the generator could supply a matching DC voltage, you risk overloading the supply source (the generator).

The (mppt) based) charge controller would "think" like this:

<mmpt program inside>
Ah, I'll start slow: gimme 10W watts.
Ok, that went fine, now give me 20W... Ok, still fine, 30W please. Oh that supply voltage still looks good, 40W please...50W...60W...70W.....
.....and it wont stop until it either the charge controller is at it's limit .... or the supply source is overloaded.
</mmpt program inside>

For a solar application this is great because you would want to extract as much enery out of the solar panel(s).
Once you hit absorbtion, the algorithm will change, and only draw as much current as is needed for maintaining the absorbtion voltage (for the attached batteries).


Greetings,
 
Slideshow boring ... losing consciousness ... just gonna take a quick nap on this tiny ad ...
GAMCOD 2025: 200 square feet; Zero degrees F or colder; calories cheap and easy
https://permies.com/wiki/270034/GAMCOD-square-feet-degrees-colder
reply
    Bookmark Topic Watch Topic
  • New Topic