Does anyone make an inverter that can send power directly from the panels to a 240 volt system if a battery bank is depleted?
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Originally posted by Murby View PostDoes anyone make an inverter that can send power directly from the panels to a 240 volt system if a battery bank is depleted?
If you want to do that without a grid (or batteries) present right now your only option is the SMA Secure Power option. It's 120V but you can use a transformer to get to 240V.
However, your question doesn't make a lot of sense. If you have no power from the solar arrays, and no energy in the battery, you can't do anything at all. If you have power from the arrays and no energy in the battery, you can charge the batteries and run a conventional inverter with the power. You don't even need to be charging the batteries. As long as your outputs match your inputs the voltage will remain fairly constant and the inverter will work. -
The question is kind of suspicious.
Do you want a legal hybrid grid tie system or are you looking to somehow send power to the grid illegally from an off grid solar/battery system?Comment
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If the battery bank is depleted (low enough SOC that you do not want to draw it down any further) the inverter (off-grid or hybrid) will continue to work just fine as long as the panel power is enough to meet your loads.
If the battery bank is damaged (cannot safely deliver or accept current at its nominal voltage) then no inverter will continue to work except a pure grid tie inverter.SunnyBoy 3000 US, 18 BP Solar 175B panels.Comment
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Perhaps I should have been more clear.
In an off-grid situation, is there an inverter out there that can utilize the full power of the solar panels and output 240 volts?
For instance, lets assume the battery bank is fully charged and I want to run a 240 volt load but I don't want to drag down my batteries.. The sun is shining and I want to use the excess power directly from the panels instead of putting the drain on the batteries which I might want to save for later.
Are there any inverters out there capable of doing this? Or is the only option a battery powered inverter?
I have an SMA grid tied system with a 2000 watt secure power supply.. I'd like to purchase an inverter that can do the same thing only with much larger capacity. I know there are no grid tied systems so I'm wondering about off grid systems.
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Originally posted by Murby View PostPerhaps I should have been more clear.
In an off-grid situation, is there an inverter out there that can utilize the full power of the solar panels and output 240 volts?
For instance, lets assume the battery bank is fully charged and I want to run a 240 volt load but I don't want to drag down my batteries.. The sun is shining and I want to use the excess power directly from the panels instead of putting the drain on the batteries which I might want to save for later.
Are there any inverters out there capable of doing this? Or is the only option a battery powered inverter?
There are two kinds of systems with batteries. DC coupled and AC coupled. The majority of the bimodal systems are DC coupled.
There is no magical switching of the current from battery to inverter though.
The charge controller puts power on the DC bus. Both the inverter and the batteries are on the bus. IF the inverter pulls power at a rate less than the charge controller is putting out then the inverter is not pulling from the batteries (in fact the batteries are being charged).
If the inverter pulls at a rate higher than the charge controller is putting out then it will pull from the batteries AND the charge controller (discharging the batteries).
There are bimodal inverters that are 240V and there are ones that are 120V that can stack to make 240V.
Originally posted by Murby View PostI have an SMA grid tied system with a 2000 watt secure power supply.. I'd like to purchase an inverter that can do the same thing only with much larger capacity. I know there are no grid tied systems so I'm wondering about off grid systems.
There are many that can do this and much more securely, can be wired in, and have batteries.
Outback makes quite a few and they are grid tied as well.OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNHComment
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Originally posted by Murby View PostPerhaps I should have been more clear.
In an off-grid situation, is there an inverter out there that can utilize the full power of the solar panels and output 240 volts?
For instance, lets assume the battery bank is fully charged and I want to run a 240 volt load but I don't want to drag down my batteries.. The sun is shining and I want to use the excess power directly from the panels instead of putting the drain on the batteries which I might want to save for later.
Are there any inverters out there capable of doing this? Or is the only option a battery powered inverter?
I have an SMA grid tied system with a 2000 watt secure power supply.. I'd like to purchase an inverter that can do the same thing only with much larger capacity. I know there are no grid tied systems so I'm wondering about off grid systems.
I am not aware of any device that can convert the DC to AC without having a battery source in between except for a grid tie inverter. Although that does not mean someone doesn't make that type of unit.Comment
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Originally posted by Murby View PostIn an off-grid situation, is there an inverter out there that can utilize the full power of the solar panels and output 240 volts?
For instance, lets assume the battery bank is fully charged and I want to run a 240 volt load but I don't want to drag down my batteries.. The sun is shining and I want to use the excess power directly from the panels instead of putting the drain on the batteries which I might want to save for later.
I have an SMA grid tied system with a 2000 watt secure power supply.. I'd like to purchase an inverter that can do the same thing only with much larger capacity. I know there are no grid tied systems so I'm wondering about off grid systems.
1) Inverters are designed to work with low impedance inputs, not the higher impedance input of a solar array (or the output of an MPPT.)
2) Most AC loads have some surge associated with them. You need some storage to provide power during that surge. The alternative would be to put in a 20kw array to handle a few kw of load, which isn't economical.
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I'm off grid, and when batteries are full, I can add 240V loads till I match the output of the solar array. Manually. Don't know of any way to do it automatically.Powerfab top of pole PV mount (2) | 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-ListerComment
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Originally posted by Mike90250 View PostI'm off grid, and when batteries are full, I can add 240V loads till I match the output of the solar array. Manually. Don't know of any way to do it automatically.Comment
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Originally posted by Murby View PostDoes the power go directly from the panels to your load or does it have to go through the battery bank first?
The Charge controller, Inverter, and batteries are all on the same bus.
The power does not instantly charge and discharge from the batteries. At any instant you are either charging or discharging the batteries or neither but not both.OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNHComment
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You're off grid so you have a 240 volt split phase inverter/charger hooked to a battery bank yes? Does the power go directly from the panels to your load or does it have to go through the battery bank first?Powerfab top of pole PV mount (2) | 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-ListerComment
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With a Sunny Boy + Sunny Island setup, the Sunny Boy(s) will generate the 120 VAC directly to the in-home micro-grid & power devices, then the Sunny Island would charge the battery bank.Comment
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