from12v to 24v with same items ....

[zolar]

thanks ampster , thanks sunking ,for your time to read my topic and reply
and thanks to all who took apar either reading or replying
I will wait for a day that I can put a pic
sorry for bothering you all , and taking much of your time.

[Mike90250]

hi all again....
....... will it work if I use step up transformer from 12v to 24v fitted between panels and charge controller ??........

This is my second peeve about under informed solar power enthusiasts.

DC transformers. The do not exist.
You can buy a DC - DC converter to increase or decrease DC voltage. it is an active electronic circuit. A transformer is AC only and passive.


And my first peeve (dare I say the D word ? ) Diodes. Do I need a diode? do I need a bridge diode? my batteries wont charge, how do I install a diode?
Add on diodes in solar, went obsolete in the 70's when the Blocking function was incorporated into charge controllers with an active FET
Replacing Bypass Diodes in panels that were fried by shade, is a the only valid reason to purchase a diode.

[zolar]

hi mike,,,

This is my second peeve about under informed solar power enthusiasts.

DC transformers. The do not exist.
You can buy a DC - DC converter to increase or decrease DC voltage. it is an active electronic circuit. A transformer is AC only and passive.

may be yes , I didn't say the correct word ( I should had said converter instead of transformer ) or at least a ( device ) , sorry my bad English.
but after that and finally ,,, I said to install that device after the batteries and before the inverter .

anyway don't bother about it.
cuz I feel some members may don't like this discussion , , if any else said it I would replyed for him ,,,
but I won't reply for sunking (always I got benefit from his topics he wrote or replyed , I really learned a lot from him,,, he will always be a master for me and I am as you said just an enthusiast.

[Mike90250]

thanks ampster for your post ,
....
I keep my system as it is and I step up the voltage to 24v by using that transformer putting it after batteries and before the inverter
( the load will deal with 24v not 12v and the storage is still as 400 amh not reduced to 200 amh .
I don't think I can make more clearly than that

Unless your 24v inverter is a very small inverter and has only small loads, it's not likely going to work well with any gadget between it and the batteries. Inverters consume wildly varying amps, 120 times a second, and would require a very robust converter AND a beefy capacitor if there was any power involved over 50 watts or so.

This is why we stress repeatedly the importance of robust cables between the battery and inverter, the current surges are enormous and will trip an inverter off-line from undervoltage faster than your voltmeter can read it.

[Sunking]

sorry for bothering you all , and taking much of your time.

You are not bothering us. Now that I know English is not your first language changes things. There is a very simple solution for you. Does not require you to buy anything, just reconfigure your panels and batteries.

You said:

if I have 12v system ( 12v panels , going to mppt charge controller 60amps connected to 2x battery each 200amh connected parallel

How many of these 12 volt panels do you have, and how are they configure? Regardless of the battery voltage being 12 or 24 volts, last thing you want to do is wire the panels in parallel using an MPPT Controller. Doing so just defeats the whole purpose of the MPPT controller. You can charge a 12 volt battery with 120 volt panels assuming the Charge Controller Input Voc is 150 volts or higher. You want to run the panel voltage as high as the controller allows as this maximizes efficiency, keeps material cost as low as possible, and minimizes fire risk.

So answer me these two questions, and I can tell you how to get where you want to go at minimum cost and maximum efficiency.

1. How many panels do you have, and what are the specifications? Pmax, Voc, and Imp. The specs should be on the manufacture nameplate.
2. Make and Model Number of your Charge Controller?

Essentially what I am going to tell you is to wire all your panels in series, and wire your batteries in series. That's all that needs to be done. Nothing to buy or breakdown on you. Only catch maybe is if you have a Prime Number of panels greater than 3. Prime Numbers do not work like 5, 7, 11, 13, 17...... With a Prime Number you only have two configuration options of all in parallel the absolute last thing in the world you want to do, or all in Series is exactly what you want to do, but there is a catch. Depending on the Charge Controllers maximum Voc input voltage, and the panels Voc rating limit the number of panels you can wire in series. If your controller has a 150 Voc, and you really have 12 volt battery panels with a Voc = 22 volts you can get as many as 5 panels in series assuming you do no tlive in a cold climate.

One last comment. If you have not bought any panels yet, last thing you want is 12 volt battery panels. MPPT Controllers antiquated low voltage panels. 12 volt battery panels are a lot more expensive than higher voltage Grid Tied Panels. So if you have not bought panels yet you are in good shape. But we can make the 12 volt battery panels work if that is what you have already.

So answer my 2 questions and lets get you going OK?