Controller section

Leehamrick
Registered Users Posts: 17 ✭
In another post I gave the specifications on my panel and controller.
I found out that the PWM controller that I have will not work well with the panel I intend to use.
I would like to know if this controller would be suitable for this panel.
I will be using two 12 volt deep cycle batteries
Specifications on the Panel,,
Max power 235w
Max power voltage 29.44
Max power current 8.02 A
Open circuit voltage 37.21
12 volt 24 volt
Rated solar input 20/30A 20/30A
Rated load 20/30A 20/30A
load disconnect 11.1V 22.2V
Equalization voltage 14.6V 29.2V <30 min
Boost voltage 14.4V 28.8V <30 min
Float voltage 13.6V 27.2V
And here are the specifications on a mppt controller,,
I found out that the PWM controller that I have will not work well with the panel I intend to use.
I would like to know if this controller would be suitable for this panel.
I will be using two 12 volt deep cycle batteries
Specifications on the Panel,,
Max power 235w
Max power voltage 29.44
Max power current 8.02 A
Open circuit voltage 37.21
12 volt 24 volt
Rated solar input 20/30A 20/30A
Rated load 20/30A 20/30A
load disconnect 11.1V 22.2V
Equalization voltage 14.6V 29.2V <30 min
Boost voltage 14.4V 28.8V <30 min
Float voltage 13.6V 27.2V
And here are the specifications on a mppt controller,,
Comments
-
Re: Controller section
opps
And here are the specifications on the controller,,
Category: MPPT solar controller
Model: MPPT30 30A
Rated Voltage: 12V/24V
Max Load current: 30A
Input voltage range: 12V~20V/24V~40V
Length≤1m Charge loop drop: <0.25V
Length≤1m Discharge loop drop: <0.05V
Full charge cut: 13.7V~14.4V/27.4V~28.8V
Low voltage cut: 10.5V~11V/21V~22V
Temperature compensation: -3mv/℃/cell
No load loss: ≤20mA
Max wire area: 6mm2
Ambient temperature: -25℃—+55℃
will this work ok? -
Re: Controller section
I've pasted in your panel specs from the other post as I assume that's what you meant to have listed there.
Those specs on the "MPPT" controller indicate it does nothing for down-converting Voltage. It wants a 12 Volt panel for 12 Volts (Input voltage range: 12V~20V) and a 24 Volt panel for 24 Volts (Input voltage range: 24~40V). I'd say it's probably a Blue Sky or a useless piece of junk from China. It would not enable you to make full use of the Vmp of 29.44 of your panel on a 12 Volt system. After that point the rest of the specs don't matter much. -
Re: Controller section
Ok so what would you guys suggest? Which MPPT controller would do the job?
If possible I would like to say at or below $100 is this possible?
You have my attention -
Re: Controller section
Under $100 for an MPPT controller? I seriously doubt you'd find a real one that would work. Under $300, yes. There's simply too many components that go in to making one to allow for low cost. The cheapest 'real' MPPT controller I know of is the MS 15 MPPT: http://www.solar-electric.com/mosumpsochco.html
It has limitations too. For instance that one 250 Watt panel will "max out" the controller because the current potential is about 16 Amps. Although this means you would have "full" current longer than you would with less panel (the controller will simply "clip" the excess power).
Even Blue Sky MPPT controllers are over $200, and most of them have input or output restrictions that defeat some of the reason for getting that type of controller.
Maybe it would be cheaper in this instance to get different panels? Like two 140 Watt "true" 12 Volt panels? Example: http://www.solar-electric.com/sosp140wamum.html
If you have to spend $300 on just a controller, the "more expensive per Watt" small panels become a better deal for a small system. -
Re: Controller section
The "cheapest" good quality MPPT charge controllers we have seen around here are around $225-$300+ or so... The MorningStar 15 amp 12/24 volt controller has a lot of pretty good history here. And Rogue's last two models were really nice (30 amp @ 12/24 volt) and Marc has a new version that should be available this month (March 2013--the older models are not currently in production, so have to wait).
A good number of the $100 "MPPT" Controllers out there are not. MPPT requires a fair amount of copper (inductor) and electronics for basic operation, which costs money. And many of the inexpensive "MPPT" controllers simply are PWM controllers with "MPPT" on the label.
We are staring to read about less expensive MPPT controllers coming out of Asia, but I do not remember really seeing any reviews here yet with actual production numbers (MPPT is fairly software/hardware intensive and there are quite a few things that can go wrong--So good customer support/lots of history is a big plus).
Also, many companies tend to have lots of options (LCD displays, somewhat expensive temperature sensors, etc.). Marc's Rogue family (at least the earlier ones) had the LCD display and basic computer connections as part of the design.
Otherwise, for larger units (45 to 60 to 90 amp) MPPT units are going to be in the $500 to $600+ range.
-BillNear San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset -
Re: Controller section
Just to do the math for anybody reading this thread:
Two Solartech 140 panels @ $263 each plus one MS 20 Amp PWM controller @ $78 = $604
One Solarworld 250 panel @ $275 plus one MS 15 Amp MPPT controller @ $224 = $499
Difference in output current between the two: <1 Amp on 12 Volt system.
(The 140's put out 7.8 Imp for combined current of 15.6, the 250 would be limited to 15 Amps by the controller.)
But sometimes you can get bargains if you look around. A couple of discontinued or blemished 140 Watt panels might be had for less than $1 per Watt which would turn the tables in their favour. -
Re: Controller section
it may also be possible to get a remanufactured classic controller as they started selling them recently over at midnight solar.
Categories
- All Categories
- 222 Forum & Website
- 130 Solar Forum News and Announcements
- 1.3K Solar News, Reviews, & Product Announcements
- 192 Solar Information links & sources, event announcements
- 888 Solar Product Reviews & Opinions
- 254 Solar Skeptics, Hype, & Scams Corner
- 22.4K Solar Electric Power, Wind Power & Balance of System
- 3.5K General Solar Power Topics
- 6.7K Solar Beginners Corner
- 1K PV Installers Forum - NEC, Wiring, Installation
- 2.1K Advanced Solar Electric Technical Forum
- 5.5K Off Grid Solar & Battery Systems
- 426 Caravan, Recreational Vehicle, and Marine Power Systems
- 1.1K Grid Tie and Grid Interactive Systems
- 652 Solar Water Pumping
- 815 Wind Power Generation
- 624 Energy Use & Conservation
- 611 Discussion Forums/Café
- 304 In the Weeds--Member's Choice
- 75 Construction
- 124 New Battery Technologies
- 108 Old Battery Tech Discussions
- 3.8K Solar News - Automatic Feed
- 3.8K Solar Energy News RSS Feed