240 Vs 120 Volt

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Okay, there is a major problem.When the power goes out and you need to run off batteries that 232 Amp hours will provide about 5kW hours of power and maybe will handle 2 kW draw at any one time.Everything you listed there will suck that battery bank flat either in an instant from too much current draw or in very short order from the high Watt hour consumption. Re: 240 vs 120 volt invertersWell I probably won't be running heat and A/C at the same time. I do have a solar clothes dryer, and a Coleman stove. I am gonna take your advice on the additional batteries though. Do you think I need a couple more panels?If it were me I'd make the most of solar that I could: panel prices are pretty low right now. Boosting the battery capacity up to 464 and then trying for 10% peak charge rate (even more if you can afford it) will give you more panel power for load running during daylight, if you can use the power at that time. If the majority of your power usage is "after sunset" the surplus panel won't do you any good because the daily power is coming mainly from batteries.What I'd usually call for: 464 Amp hours with DOD of 25% (about 5.5 kW hours daily) and 2800 to 3000 Watts of panel. If you can use lots of power during the day you could increase the array even further. Well I probably won't be running heat and A/C at the same time. I do have a solar clothes dryer, and a Coleman stove. I am gonna take your advice on the additional batteries though. Do you think I need a couple more panels? Re: 240 vs 120 volt invertersEverything is electric. Water heater, stove, dryer, radiant wall heaters with fans, and a rather large window A/C unit.Yeah, the Magnum won't run most of that stuff even if you had a big battery bank on it. We have Trane Central AC, electric water heating, electric induction/convection range, electric dryer - all off-grid. And I can say from experience that it takes either a really big inverter with a big battery bank, or an inverter with generator support capability to even run the oven in the range with any other normal loads on. The Magnum don't have gen support, and it ain't big enough to even flip the switch on the range - even if you did have a big battery bank on it.Your water heater probably has 4,500 watt elements in it. The Magnum won't run that either with other normal loads on. I swapped out the standard 4,500's in our two 55 gallon heaters with 2,000's to reduce the load on the inverter during water heating. It takes longer to heat the water (that's why we have two 55 gallon heaters to store more reserve from "good" days). But then the inverter can handle it with the smaller elements.120V inverters don't have any problems with leg balancing. Split phase inverters do. So it's possible (and not really even that hard) to leg overload a split phase inverter with normal 120V loads too. So basically, I see no reason to buy a split phase inverter unless you buy a more capable one with gen support if you want to run your 240V stuff with off-grid power. The Magnums are fine for off-grid people who need to run a 240V well pump and don't want to use a transformer on a 120V inverter. But they are woefully inadequate for handling any real 240V loads beyond that.Just my 2 cents.--Chris . Everything is electric. Water heater, stove, dryer, radiant wall heaters with fans, and a rather large window A/C unit. Re: 240 vs 120 volt invertersFor what it's worth you can parallel two Magnums. But then cost wise you're better off buying a Radian or XW6048. Re: 240 vs 120 volt invertersFor what it's worth you can parallel two Magnums. But then cost wise you're better off buying a Radian or XW6048.Outback has another split-phase system too that has two inverters stacked on one panel - can't remember the name of it. But it don't have gen support capability, so you still got a nightmare trying to run heavy 240V loads with off-grid power. Most people can't afford the batteries it takes to run one of those big inverters at Full Dawg.--Chris . For what it's worth you can parallel two Magnums. But then cost wise you're better off buying a Radian or XW6048. Re: 240 vs 120 volt invertersIf it were me I'd make the most of solar that I could: panel prices are pretty low right now. Boosting the battery capacity up to 464 and then trying for 10% peak charge rate (even more if you can afford it) will give you more panel power for load running during daylight, if you can use the power at that time. If the majority of your power usage is "after sunset" the surplus panel won't do you any good because the daily power is coming mainly from batteries.What I'd usually call for: 464 Amp hours with DOD of 25% (about 5.5 kW hours daily) and 2800 to 3000 Watts of panel. If you can use lots of power during the day you could increase the array even further. Around 4kW.Yeah. Two more panels and I would be at 2800. Just have to find a place to mount them. For the time being I have room for 8. I think two strings of eight batteries is a good idea if I can keep them charged up. If it were me I'd make the most of solar that I could: panel prices are pretty low right now. Boosting the battery capacity up to 464 and then trying for 10% peak charge rate (even more if you can afford it) will give you more panel power for load running during daylight, if you can use the power at that time. If the majority of your power usage is "after sunset" the surplus panel won't do you any good because the daily power is coming mainly from batteries.What I'd usually call for: 464 Amp hours with DOD of 25% (about 5.5 kW hours daily) and 2800 to 3000 Watts of panel. If you can use lots of power during the day you could increase the array even further. Re: 240 vs 120 volt invertersFor what it's worth you can parallel two Magnums. But then cost wise you're better off buying a Radian or XW6048.Took a look at the XW648 on the store site. Its rated at about 1.5 times the Magnum's output. Two Magnums would be more inverter and I could spread the cost out over time. Gonna have to think on that a bit. For what it's worth you can parallel two Magnums. But then cost wise you're better off buying a Radian or XW6048. Re: 240 vs 120 volt invertersYeah, the Magnum won't run most of that stuff even if you had a big battery bank on it. We have Trane Central AC, electric water heating, electric induction/convection range, electric dryer - all off-grid. And I can say from experience that it takes either a really big inverter with a big battery bank, or an inverter with generator support capability to even run the oven in the range with any other normal loads on. The Magnum don't have gen support, and it ain't big enough to even flip the switch on the range - even if you did have a big battery bank on it.Your water heater probably has 4,500 watt elements in it. The Magnum won't run that either with other normal loads on. I swapped out the standard 4,500's in our two 55 gallon heaters with 2,000's to reduce the load on the inverter during water heating. It takes longer to heat the water (that's why we have two 55 gallon heaters to store more reserve from "good" days). But then the inverter can handle it with the smaller elements.120V inverters don't have any problems with leg balancing. Split phase inverters do. So it's possible (and not really even that hard) to leg overload a split phase inverter with normal 120V loads too. So basically, I see no reason to buy a split phase inverter unless you buy a more capable one with gen support if you want to run your 240V stuff with off-grid power. The Magnums are fine for off-grid people who need to run a 240V well pump and don't want to use a transformer on a 120V inverter. But they are woefully inadequate for handling any real 240V loads beyond that.Just my 2 cents.--ChrisI won't be turning most of 240 stuff on all at once, or I'll leave it on the grid until I build up to it. It would be possible to re-arrange the 120 loads at the breaker box to balance the two legs to some degree, right? Yeah, the Magnum won't run most of that stuff even if you had a big battery bank on it. We have Trane Central AC, electric water heating, electric induction/convection range, electric dryer - all off-grid. And I can say from experience that it takes either a really big inverter with a big battery bank, or an inverter with generator support capability to even run the oven in the range with any other normal loads on. The Magnum don't have gen support, and it ain't big enough to even flip the switch on the range - even if you did have a big battery bank on it.Your water heater probably has 4,500 watt elements in it. The Magnum won't run that either with other normal loads on. I swapped out the standard 4,500's in our two 55 gallon heaters with 2,000's to reduce the load on the inverter during water heating. It takes longer to heat the water (that's why we have two 55 gallon heaters to store more reserve from "good" days). But then the inverter can handle it with the smaller elements.120V inverters don't have any problems with leg balancing. Split phase inverters do. So it's possible (and not really even that hard) to leg overload a split phase inverter with normal 120V loads too. So basically, I see no reason to buy a split phase inverter unless you buy a more capable one with gen support if you want to run your 240V stuff with off-grid power. The Magnums are fine for off-grid people who need to run a 240V well pump and don't want to use a transformer on a 120V inverter. But they are woefully inadequate for handling any real 240V loads beyond that.Just my 2 cents.--Chris. Re: 240 vs 120 volt invertersIt would be possible to re-arrange the 120 loads at the breaker box to balance the two legs to some degree, right?To a certain extent you can. It depends on how big the loads are. For instance, let's say you throw a pizza in the microwave and turn it on. Then your wife fires up her hair dryer. A 120V inverter won't have a problem with that. A split phase inverter will if they're both on the same leg. With split-phase, even if you have your loads perfectly balanced, say at 2,000 watts, and you turn on another big 1,500 watt 120V load the inverter goes into leg overload.We had 120V only for many years with a transformer to run our well. Never had a problem with it. We went to dual 4024's and besides being horribly inefficient running dual inverters we all sorts of problems with leg balancing, no matter what I did in the Main panel. We then put in a single 5548 with a PSX-240 and that worked MUCH better, but was a little underpowered for our loads. So we put in the XW6048 instead and I got the PSX-240 on the distribution panel to keep the inverter and gen leg-balancedAttachment not found.While the balancing transformer is not technically needed, it greatly enhances the efficiency of both the generator and inverter at high loadings.Also, two Magnums are not more inverter than a single XW6048. The efficiency isn't even close and the big XW will handle huge overloads that exceed the rating of both Magnums for a long time before it overheats. The Magnums also have problems with voltage regulation - one of our off-grid neighbors a hike thru the woods here bought a new PAE and they can't even run their washing machine without the lights in the house blinking like a disco. Other folks have noted this problem with them too. The big XW is a beast by comparison. JUST the transformer in a XW weighs more than a whole Magnum inverter. Just sayin'.Edit:With the XW you also get Generator Support. The Magnums, stacked or not, don't have it.--Chris . It would be possible to re-arrange the 120 loads at the breaker box to balance the two legs to some degree, right? Re: 240 vs 120 volt invertersAn XW will also take a 12 kW "hit" and can be stacked. So can a Radian (8kW surge to 16).Using an autotransformer on the Magnum's output would handle the leg balancing if this is likely to be an issue. Whether or not it is depends on the severity of the imbalance. I believe the trouble spot is actually quite high; around 70% difference.The real problem here is the number of high Wattage 240 VAC loads on the list. If you could leave them on the grid you'd be better off. Which begs the question of why you are doing this? Re: 240 vs 120 volt invertersI see that you have the grid. It would be lots easier and lower cost to be gridtied. Use a grid tied inverter instead of battery inverter. More efficient and less cost . Re: 240 vs 120 volt invertersThe real problem here is the number of high Wattage 240 VAC loads on the list.Yes! With only 464ah of battery capacity you are only roughly 1/3 of the way to the battery capacity you need to run a 6048 at full load. A 6048 will totally kill your fully charged 464ah bank in less than 30 minutes at full load. That's not enough time to even preheat the oven and make a pizza for supper.Do NOT underestimate the battery power it takes to run one of these beasts. The specs on the battery tag don't mean diddly when you load two little strings of golf cart batteries with a big inverter. The voltage will sag so bad under load that the inverter will shut down.However, the huge 240V loads in most homes are intermittent loads, while the average loads are quite reasonable. So there IS a way to run virtually anything you want to run with off-grid power that is efficient, and doesn't cost an arm and leg to do it. And that's with an inverter with Generator Support. Not many people know what this feature does, much less use it. And that's why I did a demonstration once with our old SW Plus system to show what it's all about.This might be a good time for verdigo, being he has an all-electric home, to review the Generator Support Thread:http://forum.solar-electric.com/showthread.php?18459-Demonstration-of-Generator-Support--Chris . The real problem here is the number of high Wattage 240 VAC loads on the list. Re: 240 vs 120 volt invertersYThis might be a good time for verdigo, being he has an all-electric home, to review the Generator Support Thread:http://forum.solar-electric.com/showthread.php?18459-Demonstration-of-Generator-Support--ChrisThe generator support is a nice feature. I could probably get by with the XW4548. That PSX-240 is an interesting piece of equipment as well. Thanks for all the input. YThis might be a good time for verdigo, being he has an all-electric home, to review the Generator Support Thread:http://forum.solar-electric.com/showthread.php?18459-Demonstration-of-Generator-Support--Chris. Re: 240 vs 120 volt invertersAn XW will also take a 12 kW "hit" and can be stacked. So can a Radian (8kW surge to 16).Using an autotransformer on the Magnum's output would handle the leg balancing if this is likely to be an issue. Whether or not it is depends on the severity of the imbalance. I believe the trouble spot is actually quite high; around 70% difference.The real problem here is the number of high Wattage 240 VAC loads on the list. If you could leave them on the grid you'd be better off. Which begs the question of why you are doing this?I think Chris has me sold on the XW, but I think the XW4548 will suit me. (About the same money as the Magnum) Why am I doing this? I take care of my father who is a shut in. He is tethered to an oxygen concentrator, a dehumidifier, and an air conditioner. Its mainly for back-up power for those items. The other reason is for something to do. Its cheaper than boats and classic cars, which may get used 10 or so times in a year. I have always been a car guy, and any car guy will tell you that more power is better.8) . An XW will also take a 12 kW "hit" and can be stacked. So can a Radian (8kW surge to 16).Using an autotransformer on the Magnum's output would handle the leg balancing if this is likely to be an issue. Whether or not it is depends on the severity of the imbalance. I believe the trouble spot is actually quite high; around 70% difference.The real problem here is the number of high Wattage 240 VAC loads on the list.