A tip for our readers wanting a good controller for a sub 2000 watt system. After research via YouTube I thought it wise to buy the eSmart3 40A version of the controller ( $175 delivered ) to future proof the system somewhat.
Photo is from the seller on ebay I purchased from
Advanced MPPT control algorithm, MPPT efficiency ≥
99.5%,Machine conversion efficiency up to
98%
DC
12V/24V/36V/48V automatic recognition
Maximum PV input voltage up to
DC130V (20A 30A 40A );150V (50A 60A)
3-Stage charge: (constant current, constant voltage, floating charge) to extend the battery life
Discharge mode: ON/OFF mode PV voltage control mode.
4 kinds of batteries (Sealed lead acid,Vented, Gel, NiCd). Other kinds can be defined by user.
CE,ROHS,FCC certifications 2 years warranty
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The system
Currently in process of piecing together a small PV system using 100w semi flex panels.
So far just 2x 100w panels and this charge controller so Im still a ways off
For now thinking of getting about 150AH in 12v batteries to get the system up and running , then ad panels and batteries as they are acquired.
Suggestions correction tips and advice needed to avoid making dangerous or expensive errors.
So far i have these few things to consider for sizing a battery bank to a array [/B]
1000W of solar panels gives about 70A of charge current into 12V. Lead acid batteries cannot be fast charged
You want the charge current to be 1/10th of the Ah rating of the battery.
Would need a 700Ah battery to handle the current. 20 of the 35Ah batteries.
If the battery is smaller you are wasting the charge current that is available from the solar panels.
You should not move more than 50% of the battery capacity each day.
700Ah in batteries = 350Ah per day in and out , 350Ah * 12V = 4200Wh per day
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Using that formula converted from 1000w panels to just 200w in panels , 700AH minus 80% = 140AH averaged out to 150AH battery
The semi flex panels are made up from Sunpower back contact cells
Things I need
Panel disconnect switch
Fuses possibly a breaker switch
Power line from panels to controller / batteries.
Things I don't know I need
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