12/24v hook up?

[discowhite]

i got my 100w panel today, sitting in the sun at 9am i have 10.98v and 23.2v depending on where multi meter was placed on the terminals.

now, i have a 12/24v 20amp reg coming so im wondering if its better to hook it up on the 24v side to take advantage of the 6amps max, or dosnt it matter?
the 12v side of the panel has a 5amp max rating...

cheers phil

[langy]

I was reading you post about the specs for the 80w panel - look under the open circuit bit and you'll see that it's a a lot higher than under load. I'd bet that the 23v you found is the open circuit max for the 100w panel. Put a headlight bulb on it and see what it does under load. I'm betting that it'll drop a fair bit - and that gives you the right input for the regulator.

[miky]

i got my 100w panel today, sitting in the sun at 9am i have 10.98v and 23.2v depending on where multi meter was placed on the terminals.

now, i have a 12/24v 20amp reg coming so im wondering if its better to hook it up on the 24v side to take advantage of the 6amps max, or dosnt it matter?
the 12v side of the panel has a 5amp max rating...

cheers phil

Well... if it is sitting in the sun with no load, the 10.98V is obviously never going to charge a 12V battery!

[weeds]

run wires from the 23.2 output on the solar panel, neither of my regulators had and option on the input side of it, i guessing you won't either, the output should be straight forward as well which should give you around 13V

[discowhite]

Well... if it is sitting in the sun with no load, the 10.98V is obviously never going to charge a 12V battery!

thanks for the usefull post:censored:

cheers phil

[miky]

Happy to oblige... any time I can help ;)

[discowhite]

your incorrect anyway, if im at 10.98v output and the battery is at 9v...what happens:eek:

cheers phil

[Mandrake]

I'm a little lost here - does your panel ( or is it panels ? ) have 2 output cables one for 24 volt and one for 12 volt ? Just curious because none of mine do ... Anyway assuming its on the 12 v side the short-circuit volts should be somewhere near 21 v ... not half of it .. likewise the 24 v side should be up near 40 v ... Shortcircuit amps can be measured directly across the terminals when disconnected from controller and loads .. and they should be about 6.8 Amps and 3.4 Amps respectively .. Most controllers will not put out charge voltage until they are connected to the battery .. and again most controllers will select the input voltage automatically switching between 12 and 24 v .

Cheers

Steve

[Blknight.aus]

some older style panels have a center tap. I think but cant verify that its used when your charging a series battery setup.

[discowhite]

I'm a little lost here - does your panel ( or is it panels ? ) have 2 output cables one for 24 volt and one for 12 volt ? Just curious because none of mine do ... Anyway assuming its on the 12 v side the short-circuit volts should be somewhere near 21 v ... not half of it .. likewise the 24 v side should be up near 40 v ... Shortcircuit amps can be measured directly across the terminals when disconnected from controller and loads .. and they should be about 6.8 Amps and 3.4 Amps respectively .. Most controllers will not put out charge voltage until they are connected to the battery .. and again most controllers will select the input voltage automatically switching between 12 and 24 v .

Cheers

Steve

after a week of playin around with the panel and reg ive worked it out...i got lost in the translation from chinese to engilsh....we good use quality hi products...that type of translation:eek: the panel has 3 connections but im now assuming that only 2 are used, the ones that give 20+volts.

cheers phil

[Redback]

I'm glad you worked it out, I was a bit worried about the outputs you first mentioned, my 20W panel puts out 19.6 in full sun and 16.5 in the shade:eek:

Baz.

[ATH]

The more I read about solar panel outputs etc. the more confused I become. Although I readily admit my confusion is my most normal state of mind when it comes to electrics.
My problem is I bought a pair of Primus 80watt panels which has a regulator on the back and it states that the output is 17.2v.
My problem, is can I connect these directly to the caravan battery via an Anderson plug or should I have a voltage regulator between the battery and panels?
The 12v shop in Perth says "No" the regulator on the back will adjust the voltage, but Primus say "Yes' you need one sense battery charge and to step down the charge for when the battery is full.
Anyone out there can assist in simple terms as I don't want to cook the battery with too high a voltage going in.
Cheers.
Alan.

[bee utey]

The more I read about solar panel outputs etc. the more confused I become. Although I readily admit my confusion is my most normal state of mind when it comes to electrics.
My problem is I bought a pair of Primus 80watt panels which has a regulator on the back and it states that the output is 17.2v.
My problem, is can I connect these directly to the caravan battery via an Anderson plug or should I have a voltage regulator between the battery and panels?
The 12v shop in Perth says "No" the regulator on the back will adjust the voltage, but Primus say "Yes' you need one sense battery charge and to step down the charge for when the battery is full.
Anyone out there can assist in simple terms as I don't want to cook the battery with too high a voltage going in.
Cheers.
Alan.

To put it simply, the voltage output of a solar panel varies widely with load. High load, low voltage. Low load, high voltage. The 17.2V is either the open circuit voltage or the maximum power voltage. If you connected such a panel to a flat battery it would charge it happily. Unfortunately it wouldn't stop pushing current when the battery was full. Battery fizz-out being the result. So all solar panels should run through a regulator, except in the special case of a trickle charger on a large wet cell battery. Two panels can be connected to one regulator with the ability to handle the maximum output of both together. You need to take a close look at the 'regulator' and see that it is actually that and not just a junction box.

[Blknight.aus]

ok, in a pinch YES you can hook a panel directly to a battery and charge it...
however

DONT..

you should have some kind of voltage regulating device in there.

heres the ones I use

the bare bones 80w panel jobbie (http://jaycar.com.au/productView.asp?ID=AA0348&form=CAT2&SUBCATID=1004#12)
not as efficient as you'd like but Ive been running one of these for about 8 years now and it keeps the engle happy.

A multi panel one (http://jaycar.com.au/productView.asp?ID=MP3126&form=CAT2&SUBCATID=1004#12) not as effective as it could be till your pushing 150+w of panels up to there so long as the panels are under 80w a piece I just parralel 2 of the cheapies. The main reason for this working better is each panel is its own entity and any drop in output of one doesnt effect the other.

This little buety (http://jaycar.com.au/productView.asp?ID=MP3129&form=CAT2&SUBCATID=1004#12) is one for breaking into more permanent setups I'll put this one on motor homes and trailers that have a semi permanant setup primarily because this units not all that happy wet and offers usage monitoring so you can budget your amps.

And heres that last ones big brother (http://jaycar.com.au/productView.asp?ID=MP3735&form=CAT2&SUBCATID=1004#12) Same features but with more amps

if you dont already have the panels, Im starting to reccomend wind (http://jaycar.com.au/productResults.asp?whichpage=1&pagesize=10&keywords=&MID=12&SUBCATID=1005&SSUBID=852&form=CAT2#12) technology, the small VAT's are pretty good.