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Cabin System Help

Progress!

Everything is running great.
Could you please give up a close up of the back of the array so we can see how its mounted? Can you also tell us the items you used to make that mount?
 
Could you please give up a close up of the back of the array so we can see how its mounted? Can you also tell us the items you used to make that mount?

I had a local fab shop weld up the black steel bracket and I drilled the holes for the u-bolts. The frame itself is made out of unistrut and a piece of 2" black pipe. I "rounded" the 6x6 post so that I can rotate the array in all directions. I would use a 6" steel pipe if I was to do it again.

Let me know if you have other questions.
 

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I suppose if anyone else is looking to do something similar, On the post bracket, if you extended the lenght of the top plate, and put the U-bolts there instead of extending the front plate up, You would likely not need to notch the panel edges to clear the flag on the front plate that is sticking up.
 
Glad to hear it. Unfortunately, I have to burst your bubble. Even if that's a 8x8 pole, it may not be adequate for peak winds in your area. A 30 mph wind perpendicular to your panels will put about an 800# load on your array. Even if the panel center is only 5' above ground, that would be a 4000ft-lb moment trying to snap your pole at the base.

You have a lot of trees, so hopefully, you get negligible wind. If you've ever had storms with high winds, I would encourage you to use a steel pipe.

Wood posts can be fine as panel mounts, just not single pole cantilevered-type.
What would be causing the 30amp circuit breaker to trip? Its only happened twice since the system has been up and running (1 month).

The only constant drawn is a small refrigerator (297 kWh/yr) and all my lights are 12v (.4 amps) which I only leave 1 on regularly. The most amperage I've ever experienced (not including the fridge) is 7-8 amps.

Thoughts?
Glad to hear it. Unfortunately, I have to burst your bubble. Even if that's a 8x8 pole, it may not be adequate for peak winds in your area. A 30 mph wind perpendicular to your panels will put about an 800# load on your array. Even if the panel center is only 5' above ground, that would be a 4000ft-lb moment trying to snap your pole at the base.

You have a lot of trees, so hopefully, you get negligible wind. If you've ever had storms with high winds, I would encourage you to use a steel pipe.

Wood posts can be fine as panel mounts, just not single pole cantilevered-type.
What would cause the 30amp circuit breaker to trip? Its only happened twice since the system has been up and running (1 month).

The only constant drawn is a small refrigerator (297 kWh/yr) and a 12v (.4 amp) light bulb. The most amperage I've ever witnessed is 7-8amps (not including the fridge) while I had everything on (12v lights and 2 12v ceiling fans).

Both times the breaker has tripped I have not been there and just the fridge and 1 bulb were on.

Thoughts?
 

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I'm seeing the 30A breaker between the SCC and the batteries. Based on the prior information in this thread, you needed a 50-60A charge controller.

You appear to have batteries in parallel for 12V. If you have more than 12V * 30A = 360W of solar, then you're pushing more than 30A through that breaker.

Undersized breaker.

Fuses/breakers should be 1.25X the rating of the wire.
 
Yes, 60amp SCC....so I need a 75amp breaker (1.25x60)? The wire size is 2awg.
 
2awg is overkill and would suggest a higher breaker, but 75A works fine. Note that cheap Amazon breakers may be fine or they may be junk.
 
2awg is overkill and would suggest a higher breaker, but 75A works fine. Note that cheap Amazon breakers may be fine or they may be junk.
So everything has been running great since I swapped for the 60amp breaker until yesterday. Batteries were 100% drained and everything was off. We haven't had much sun so I'm thinking that's the issue but I want to make sure. I disconnected each battery and tested them individually and each is reading out 11.3v or 11.4v...is this common? We have a little sun today and when the panels are receiving direct sunlight the battery capacity spikes to 50 or 60% but as soon as the sun goes behind a cloud, the capacity instantly drops back to the 10-15% range. I've noticed this in the past on sunny days when the sun sets, the battery capacity will go from 100% to 60% really quickly.

Are my batteries bad?
 
So everything has been running great since I swapped for the 60amp breaker until yesterday. Batteries were 100% drained and everything was off. We haven't had much sun so I'm thinking that's the issue but I want to make sure. I disconnected each battery and tested them individually and each is reading out 11.3v or 11.4v...is this common? We have a little sun today and when the panels are receiving direct sunlight the battery capacity spikes to 50 or 60% but as soon as the sun goes behind a cloud, the capacity instantly drops back to the 10-15% range. I've noticed this in the past on sunny days when the sun sets, the battery capacity will go from 100% to 60% really quickly.

Are my batteries bad?
Today I had full sun all day. Went to the cabin early and made sure everything was off except the small refrigerator. Around noon, I checked the system again and the battery capacity was at 76% so I decided I'd turn the inverter off and left everything off (no draw on system) to see if i could get to 100%. I just returned to the cabin after sunset and the batteries are only reading 41% after a few hours of full sun and no draw....battery issue I'm assuming?
 
Batteries at 11.3-11.4 are completely discharged. "haven't had much sun" + using power + "we have a little sun" all equates to you using more power than your are collecting.

Where are you getting these % numbers? If they are not based on a programmable battery monitor, they are likely meaningless and based on voltage alone, which is consistent with the rapid changes in % capacity you describe.

"Full sun all day" from 750W of panels means AT MOST you're going to get 5*750W = 3750Wh assuming you have excellent panel orientation and tilt with full charging. Your 6X 110Ah, 12V will need AT LEAST 7920Wh of input to fully charge them. Taking inefficiencies into account, you will need the better part of 3 days of charging to ensure they are fully charged.

Any time you're talking about a % charge, please include the actual battery voltage.
 
Batteries at 11.3-11.4 are completely discharged. "haven't had much sun" + using power + "we have a little sun" all equates to you using more power than your are collecting.

Where are you getting these % numbers? If they are not based on a programmable battery monitor, they are likely meaningless and based on voltage alone, which is consistent with the rapid changes in % capacity you describe.

"Full sun all day" from 750W of panels means AT MOST you're going to get 5*750W = 3750Wh assuming you have excellent panel orientation and tilt with full charging. Your 6X 110Ah, 12V will need AT LEAST 7920Wh of input to fully charge them. Taking inefficiencies into account, you will need the better part of 3 days of charging to ensure they are fully charged.

Any time you're talking about a % charge, please include the actual battery voltage.
I'm getting the % from the readout on my SCC. I do also have a battery monitor that displays the voltage.... both were reading 11.3-11.4v.

So just to confirm, you think there is nothing wrong with the system (specifically the batteries)....just using more than I'm collecting?

Is there a way to hook up a generator to power and charge the system for times like this?
 
The evidence presented thus far suggests use greater than collection.

% from your SCC is completely worthless. It's purely voltage based, and it will change wildly. You would benefit from a programmable battery monitor:


The 350A "budget" one is pretty popular. You program it with your battery info and charging criteria, and it counts how much energy you've used.

The Victron BMV-712 is better, but it's 3-4X more expensive, though it offers bluetooth access and is more accurate.

Your inverter appears to be only an inverter. Some have inverter and charger functions where they can receive an AC source from grid or genny and charge the batteries.

In your case, a high current AC-DC converter is your best option, IMHO:

The 75A version of this:


It would be optimally run by a 1500-2000w generator and charge your 660Ah bank at 75A, which is pretty close to optimal. You would be able to use the system while charging.
 
I have a 50amp battery charger... would this essentially do the same thing as the converter when powered by a generator?
 
The converter is at its heart an AC powered battery charger, so probably.

Link charger to confirm?
 
That's what I thought. That's a 10A charger, not a 50A charger. The 50A is for boosting a battery during start.
 
Next thought....how would I hook a 400w 12v wind turbine to the system?

The turbine comes with its own charge controller. Something like this:

Merry Christmas!
 
Simply program the controller appropriately for your battery and attach to battery.

Keep your expectations on wind VERY VERY VERY low.
 
The converter is at its heart an AC powered battery charger, so probably.

Link charger to confirm?
I have thought of using a battery charger as well when we are running our generator if using heavy tools/saws etc. during the day. While we're running the generator it makes sense to charge our bank if it's not fully charged. It is a gas generator that we start manually. There is no grid-tie whatsoever.

Our battery bank is currently 190ah, but will eventually grow to approx. 300ah.
What would the optimal size charger be for our system?
 
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