Sizing Solar Controllers
rreynolds51
Registered Users, Users Awaiting Email Confirmation Posts: 2 ✭
I'm looking at 6ea 200 watt panels and I'm trying to decide whether to break it into two groups or keep it as one large one. With two groups I could use two smaller controllers. maybe a 100/50 or 60 amp. If I use it as one string I will probably need at least a 70 or 80 amp converter. If I got the calculations right. What does experience suggest? Which works better and how do I get a better idea on sizing the controller. Planning on running the panels in parallel rather than series. 12 system. Thanks
Comments
-
What voltage battery bank are you looking at (seems like 24 volt)?
How far is your cabling run from the Array to the solar charge controller?
What Vmp/Imp are your panels?
Near what major city will the installation be?
Any particular solar charge controller brands/models you are interested in using?
-BillNear San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset -
Make it a 24V system and use 1, 60A charge controller.Not sure why all the reluctance to move from 12V for systems needing larger voltageMuch easier to build up a high voltage (24 or 48V ) battery, then 17 , 12v batteries in parallel !!Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister , -
You stated 12 volts Are you in a rv?2kw array 6 345 q cells make sky blue 60 cc
6 230ah GC @36 volts
18 amp accusense charger. 3650 champion -
RV roof top solar panels Max Operating Voltage (Vmpp): 21.01Volts, Max Operating Current (Imp): 9.52Amps, Battery bank is 12vdc 400 AH Lithium batteries. We travel the southwest primarily but are based in El Paso, Tx. I like Victron CC mainly but we use to have a Tristar. Panels are on the roof so no more than 15ft from controller max.
-
IMHO, using 2 x 50-60a controllers would be better than 1 x 70-80a for two reasons; some redundancy so it isn't lights out if there's a problem with a controller, and this provides some capacity overhead.
Regularly running a controller at/near capacity can make it run hotter, reducing life expectancy, and it may derate output. In an RV, I'd probably look for one with a large heatsink in lieu of internal ventilation fan.Off-grid.
Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter -
Mppt has it's advantages. Like long runs from the charge controller to the panels. Or using higher voltage panels with low voltage batteries. But In your case with 12 volts 21 volt panels and a 15 foot run. I'd use
A (Or 2) quality adjustable pwm controller.2kw array 6 345 q cells make sky blue 60 cc
6 230ah GC @36 volts
18 amp accusense charger. 3650 champion -
my system is pole mounted and adjustable. I run 2 controllers 1 pwm 1 mppt With panels pointed directly at midday sun and battery low ~60℅ soc.
80f day at 3500 foot alt. with 400 watts on each system. Mppt or pwm I'll get 6 max amps per 100 watts. 1200 watts 72 amps.
mounted on top your amps will be less. when panels get very hot in extremely high temperatures such as yours.
They drop power. Mount them so air can circulate.2kw array 6 345 q cells make sky blue 60 cc
6 230ah GC @36 volts
18 amp accusense charger. 3650 champion
Categories
- All Categories
- 220 Forum & Website
- 128 Solar Forum News and Announcements
- 1.3K Solar News, Reviews, & Product Announcements
- 189 Solar Information links & sources, event announcements
- 886 Solar Product Reviews & Opinions
- 254 Solar Skeptics, Hype, & Scams Corner
- 22.3K 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
- 2K Advanced Solar Electric Technical Forum
- 5.5K Off Grid Solar & Battery Systems
- 424 Caravan, Recreational Vehicle, and Marine Power Systems
- 1.1K Grid Tie and Grid Interactive Systems
- 651 Solar Water Pumping
- 815 Wind Power Generation
- 621 Energy Use & Conservation
- 608 Discussion Forums/Café
- 302 In the Weeds--Member's Choice
- 74 Construction
- 124 New Battery Technologies
- 108 Old Battery Tech Discussions
- 3.8K Solar News - Automatic Feed
- 3.8K Solar Energy News RSS Feed