diy solar

diy solar

Very first off grid diy solar system initial set up Q!

12 awg is for 20A, 2400W at 120V or 4800W at 240V. Possibly you would want a 10 awg 30A cord.
I haven't used that inverter, but see if there is a setting for how much current it should draw from the input. It may be able to let you connect a smaller generator, draw no more than your setting, produce additional power from battery when needed.

Do you have a generator yet? Dual fuel would let you use propane (never goes bad like gas), tri-fuel would also use natural gas, cheap and convenient if available at your house. Some are electric start and some inverters can automatically start and stop generator.
The Growatt does indeed have a setting to limit charging current (specifically for using a generator). Or at least every manual for them I've read did.

Since she indicates she has 200 AH at 24v capacity lead acid, 0.2C is probably appropriate charge rate (correct me if I'm wrong).
That would be 40 amps. From the manual:

Program 02
Maximum charging current: To configure total charging current for solar and utility chargers. (Max. charging current = utility charging current + solar charging current)

24V model: default 60A, 10A~140A settable

Program 11
Maximum utility charging current Note: If setting value in Program 02 is smaller than that in Program 11, the inverter will apply charging current from Program 02 for utility charger

24V model: default 30A, 0A~60A Settable
 
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Do you have a generator yet? Dual fuel would let you use propane (never goes bad like gas), tri-fuel would also use natural gas, cheap and convenient if available at your house. Some are electric start and some inverters can automatically start and stop generator.

+1 for the dual fuel if you can afford it, I have the 30 lb. propane tanks for mine. Propane can be stored for emergencies and doesn't go bad like gasoline.

My Champion has performed like a champion when needed. Unfortunately it is quite loud, I plan to replace it with a quieter dual fuel model. I wish they made the better ones with electric start.

What I have (because Amazon would deliver it in 2 days, 3 days before a hurricane):


What I would like:

Wish it had electric start.
 
We seem to be having an issue with our system now.

(((We have 8 250 watt panels one all in one 3000 watt growwatt inverter. We have 8 marine deep cycle batteries. They are 12 volts wired in pairs making it 4 pairs at 24 volts.)))


We are having two problems. Over night our batteries are going way too low ( they are less than a month old) we are running 3-4 box fans, and 4 led lights, as well as one mini fridge. Before we had the mini fridge the batteries wouldn't drain but when I checked all of these things and thier usage time on a solar calculator it says we have enough to run it. The fans go for about 18 hours a day (Florida) the fridge goes all day and the lights are for 6 hours.... We should more than enough power but we don't. The second issue is we wired a 12 gauge wire about 20 ft from the generator to the AC Input and although the all in one growatt inverter recognizes it & shows it's connected.... but it is not charging the batteries and I'm not sure why?
 

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the fridge goes all day
This is new to the energy use from what I could see looking back. What fridge? Is it an AC fridge? Any watt numbers?

Just playing with numbers and making some guesses that fridge uses 75Wh per hour between cooling and idling:
75Wh x 24 h = 1800Wh
1800Wh / 25.6 = 70Ah everyday

Figuring in inverter 15% loss:
70Ah / .85 = 82Ah @ 25.6V (roughly what 3-4 of your 12V batteries can hold and supply)
 
Will the mini-fridge stay cold enough if powered off for the night?


What is no-load drain of inverter? Can that be remotely switched off with a timer, or you do it manually?
 
The Growatt does indeed have a setting to limit charging current (specifically for using a generator). Or at least every manual for them I've read did.

Since she indicates she has 200 AH at 24v capacity lead acid, 0.2C is probably appropriate charge rate (correct me if I'm wrong).
That would be 40 amps. From the manual:

Program 02
Maximum charging current: To configure total charging current for solar and utility chargers. (Max. charging current = utility charging current + solar charging current)

24V model: default 60A, 10A~140A settable

Program 11
Maximum utility charging current Note: If setting value in Program 02 is smaller than that in Program 11, the inverter will apply charging current from Program 02 for utility charger

24V model: default 30A, 0A~60A Settable

I went through all 48 settings to try and make sure it’s appropriate for using generator as back up option.. as for setting 2 I have it at 60amps is that too high?

Setting 11 I have it at 50 amps

Also for some reason I can’t change setting 10 (number of series batteries connected) it’s defaulted on 2 but I have 4 series... it’s the only setting I cannot change manually and I don’t know why

It is odd because I was able to connect and charger from generator and panel once for about 30 mins ( changed the setting 14 to solar and utility) and then I believe it tripped so I reset the plugs and checked the outlets and plugs and they were all live but now even the extension cord doesn’t work although when I test it it’s live. I’m thinking it’s some sort of electrical spec threshold setting that I just don’t know the appropriate number for...
 
Will the mini-fridge stay cold enough if powered off for the night?


What is no-load drain of inverter? Can that be remotely switched off with a timer, or you do it manually?
I’ve been turning off all house breakers at night to conserve battery including the fridge ?
 
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