Tweet
have browsed through a few threads looking for answers to some ideas i have for expanding my off grid solar , ( found the answer thank you members) i have noticed alot of talk about using highest voltage possible to save on cable costs and energy losses. the problem i see with using high voltage , such as configuring solar panels in series to save on splitters and cable thickness costs, is the cost of the charge controller. the high voltage large current CCs cost as much $$$ as the batteries and panels. iv decided to split 6 x 250w panels into 2 groups of 3 panels in parallel and use 2 seperate cheap 30amp mppt CCs . then feed these 2 seperate charge controllers into one 400ah 24v battery bank. these CCs you can pickup for $20 as opposed to a $1000 high input voltage 60amp CC. sure i need 8 x splitters for the six panels for parallel. 2 x 7meter 25 amp cables for the 2 CCs . but nothing more
-
-
I understand your reluctance to spending a lot of money on a CC. Just be careful that the lower cost MPPT CC's may not be what they claim or provide you what you really need.
You also run the risk of the two CC's connected to the same battery bank actually fighting each other since the lower expense CC do not communicate with each other.
Just giving you a tip to be careful that spending less up front may cost you a lot more later. -
I'd like to know where you're finding 30A MPPT charge controllers for $20.
WWWComment
-
here http://www.ebay.com.au/itm/251785457...%3AMEBIDX%3AIT
and b4 all the blah blah starts..
review here http://diyprojects.eu/cmtp02-disasse...ge-controller/Comment
-
Good luck with that. Read the description... it isn't even MPPT, it is PWM. Max input voltage for 24 V charging is 40 V, so you wouldn't be able to put any panels in series even if you wanted to. Without 3 stage charging or EQ functions, I hope the batteries you hook up to it aren't worth much.CS6P-260P/SE3000 - http://tiny.cc/ed5ozxComment
-
The Blah blah part is the truth you do not want to hear.It is junk and you get exactly what you are paying for. Fact is MPPT is less expensive than PWM. You out that cheap chi-com piece of junk on your panels and you turn your 250 watt panels into 80 watt panels on a 12 volt battery, 160 watts on a 24 volt battery. Go right ahead and do it.
If you go with PWM is going to force you to use very expensive battery panels that cost 2 to 6 times more than Grid Tied Panels. It takes a 300 watt PWM system to equal the power of a 200 watt MPPT.
300 watt of Battery panels is going to cost you $500 to $750, plus a cheap $40 to $50 for a decent 20 amp PWM controller. You are looking at $600
or
Buy a single 200 watt GTI panel from $180 to $300 plus a $190 20 amp top of the line MPPT controller and you are looking at $400 to $500
You want to get up to 1500 watts output. Now you are talking 2300 watts of battery panels and a cheap $150 60 amp PWM controller you are talking $4500 to $5000 for cheap Chi-Com crap off Flee Bay.
Smart money is 1500 watts of GT panels ($1000 to $2000) plus a top of the $600 80 amp MPPT controller and you are looking at $3000 at the most.
So don't give us that Blah Blah crap, we know what we are talking about. A good MPPT controller is going to cost you $10 per amp for small stuff, and goes down slightly to 7 to $8 per amp for 80 amp controllers. $1 per amp is cheap Chi-Com counterfeit off Flea Bay.
I got hundreds of Apple I-Phones for sale. $100 each. I offer volume discount.MSEE, PEComment
Comment