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diy solar

360V DC input split phase 120V/240V AC inverter

Not stupid. They are designed that way for safety. Cut power if the grid goes down to protect anyone working on the lines.

Also, hybrid inverter typically means hybrid of PV and battery inverter. At least in my definition, I could be incorrect.
 
Not stupid. They are designed that way for safety. Cut power if the grid goes down to protect anyone working on the lines.
Yes, I understand this. But it's stupid to have PV and Inverter perfectly functional during a sunny day and don't have power at home because the grid is down.

But I ask myself, what if I use a grid tie inverter and I connect it to a cheap/low power inverter who will simulate the grid?
I mean, I connect a 12vdc 300w inverter to a battery and this is my ''grid''. After I connect the powerful grid tie inverter to my 360vdc battery and connect the ''grid''... is this can work?
 
Yabert, there is tons of information out there on using a battery inverter to form a grid and keep the PV producing. But, your idea would not quite work once you dig deeper than the surface.

Most grid tie PV inverters just pump out whatever you they can manage without any thought or care about load. You would need your battery inverter to cover any difference between production and consumption, both excess production and excess consumption.

Plus you need some form of transfer switch something to disconnect from the grid and (depending on your inverter choice) reconnect to the battery inverter.

Also, depending on your location, you might need a split phase inverter and I've never seen one as low as 300w
 
That's another PV inverter. It's either not going to work with a battery or pump out it's full rated current until the battery is flat/disconnects things might go sideways if you have 2,000 watts of load as it's trying to push out 3,000 wats.

It isn't split phase, so it might work for your drier/oven (240v). It isn't going to power lights (120v)

Not UL 1741, isn't approved for use in US so it won't be permitted

Shows it has anti-islanding, so it can't be used off grid by itself. Maybe they have an option to disable that, but that's a big safety feature for them to just turn off.

Weight shows 5 kg, that's crazy light for a 3000w inverter. Probably just a typo?


Keep looking I hope you find one, but read the spec sheet. The information for charging current and the like should be in there. It is probably going say all over the marketing info that it is a battery inverter.
 
Hi all
I would like to connect my large battery pack (60 kWh (360V 167Ah) Chevy Bolt) to power my house in case of blackout, but it seem like inverters to do this are rare.
For me, it a non sense to build another 12V or 48V battery who will not be use 99% of time instead of using this large car battery actually available.

There seem to have tons of 12-24-48V off grid inverter available everywhere or grid tie inverter with 200V-500V DC input, but never off grid 200V-500V DC input inverter.

My plan, in case blackout is to turn off utility house input and connect my car to my house*.
So, is there pure sine off grid inverters with 300-400V DC input available in the 2000w-6000w range?
Please let me know.
Thanks
Yan

*for those who know the subject, there could have dangerous voltage manipulation involve in this and also car warranty legitimacy out of spec. It's not as simple than connect the J1772 to the car. I have a lot of experience with different voltage battery packs and I don't advice anybody to do this without a lot of knowledge/experience.
**sorry for the English, it's not my first language.


Have a look at this post:
I show what I put onto my vehicle... I also figured out that an APC SURT8000XLT or a SURT10000XLT supports 384v DC nominal battery input (use it with a SURT003 to get a split-phase transformer as well).

There is also another couple routes you could go. One is to go with plugoutpower.com who makes inverter solutions for vehicles, or another one is to use an MPPT charger that supports proper input voltage range, and make it work to power your inverter. Read more in the below thread too:

This should get you more up to speed on some of our other similar dicussion, since we've already been talking about this a bunch...
 
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sma sunny boy storage, pomcube netzero plus, evtv sandi 30kw unit.
 
Yes, I understand this. But it's stupid to have PV and Inverter perfectly functional during a sunny day and don't have power at home because the grid is down.

But I ask myself, what if I use a grid tie inverter and I connect it to a cheap/low power inverter who will simulate the grid?
I mean, I connect a 12vdc 300w inverter to a battery and this is my ''grid''. After I connect the powerful grid tie inverter to my 360vdc battery and connect the ''grid''... is this can work?
Be very careful with this. PV inverters are current source inverters. They will push the entirety of their PV input as output once they lock a grid signal. Depending on the inverter you are using (full H bridge) it will go back to the battery and it will begin to make the battery voltage rise until overcharge/things start to burn up including the 300W inverter. There will be nothing to stop or limit the output power of the PV inverter. Everything will burn up. You need to have both a battery inverter and PV inverter that works together (via frequency shift normally) to limit the PV inverter output based on what is required.
 
Thanks all for the goods informations.
I found another compact, low cost, nice inverter with 450vdc input.
In fact it's a water pump inverter with variable frequency output. Is it possible to obtain a fix output of 240V 60Hz with this?

Assuming the Bolt battery you are referring to is still to be permanently mounted in the vehicle, and you will use the car's original charging method for charging the Bolt battery right? You were just looking for an inverter you could use to interface with the battery on the working vehicle (to extract AC power source from)?

Because that 450v input on that inverter is only an MPPT PV input intended for solar panels. I did hear of someone using that kind of setup before to interface with a car (using a solar charger to charge a home battery bank on output), but just understand it is a one-way PV input circuit and cannot charge back to the car battery, so you will still require other means to keep the Bolt battery charged.

The only reason I bring this up is because in your original post at top of thread you mentioned:

"...connect my large battery pack (60 kWh (360V 167Ah) Chevy Bolt)"

...but it wasn't clear to me if you mean it is still in the working vehicle or you have a Bolt battery pack salvaged from a Bolt...

1607566458927.png

Also note, this is only 2.2kW inverter, doesn't seem like very large for the cost, I think there are other solutions to get more kW for the money...

Looks like it will support 60hz, but this spec sheet doesn't indicate the output voltage or whether it supports split-phase 240v/120v (not sure if that's required)...
 
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The car, well the van still work well. See the link below

I don't plan to charge the car with solar. I only want an inverter to power the house with the car during a blackout.

Hey that's a pretty fancy retrofit on the VanaBolt... I used to do cool big projects like that on cars (nothing electric though back then)... Nice work!

I should show that to my old buddy who really loves VeeDubs a lot. He has a bunch of older VW buses, I think he's had a couple Vanagons before... He might get a kick out of your project.

Anyways, the thing I'm not sure I like about that inverter example you linked to, is, about output specifics, like I don't see a voltage, and it is made for running a well pump, so does it even have some set voltage, not really sure? And it's only 2.2kW...

Also, did you mention if you needed split-phase 240v/120v or fine with just 240v / 60hz without center tap on the output?

If you want to attempt to use an MPPT PV input on an inverter, there are plenty of other inexpensive all-in-one inverters that support battery-less operation and high PV input voltage.

Here's an example we just stumbled across the other day:
Supports up to 500v input on the PV, battery-less operation...

Other example of same type, with a 3kW and a 5kW:
 
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Yes, I understand this. But it's stupid to have PV and Inverter perfectly functional during a sunny day and don't have power at home because the grid is down.

But I ask myself, what if I use a grid tie inverter and I connect it to a cheap/low power inverter who will simulate the grid?
I mean, I connect a 12vdc 300w inverter to a battery and this is my ''grid''. After I connect the powerful grid tie inverter to my 360vdc battery and connect the ''grid''... is this can work?

I think you can get what you want from SMA

Their "Sunny Boy" is a grid-tie inverter. During power failure, they can produce 120V up to 2000W without batteries, direct from the sun.


If you want you can add their 48V or 400V battery inverter for full power operation (e.g. 6kW) and continuing to run after dark. (A quality inverter to simulate the grid, which works well with the PV inverter and the grid.)
 
I think you can get what you want from SMA
Yes, it could work. But there is two things I dislike with the sunny boy. First, his price/watt who is quite high. I bet this is correct considering the quality and warranty, but there is the second point.... his dimensions ???
28.5x21x8'' Outch! Such a big inverter to have only 2000w. Compare with the INVT 2200w unit I wrote about few line upper, the SMA is two time bigger.

Considering that a good solution for me is to have the inverter permanently mounted in the Vanabolt to don't have to play/connect with 360vdc side, but only with 240vac, the SMA seem way to big.
Of course I can mount it in the house, but I don't like the fact to play with 360vdc extension cord and it remove the super nice thing to have a AC generator on wheels ?
 
Yes, this seem the only interesting solution for my needs. I don't like the fan cooling system (prefer convection cooling) and I have reserve about quality.... but this seem the only interesting solution.
 
Yes, it could work. But there is two things I dislike with the sunny boy. First, his price/watt who is quite high. I bet this is correct considering the quality and warranty, but there is the second point.... his dimensions ???
28.5x21x8'' Outch! Such a big inverter to have only 2000w. Compare with the INVT 2200w unit I wrote about few line upper, the SMA is two time bigger.

Considering that a good solution for me is to have the inverter permanently mounted in the Vanabolt to don't have to play/connect with 360vdc side, but only with 240vac, the SMA seem way to big.
Of course I can mount it in the house, but I don't like the fact to play with 360vdc extension cord and it remove the super nice thing to have a AC generator on wheels ?
Well, in fairness to me, this thread is under

not "Vehicle mounted systems"

7.7 kW Sunny Boy can be had for $1200 to $2000. Quite high?

The 2000W was only for convenience outlet, one 15A 120V outlet. Normal grid-tie operation up to 7.7 kW depending on model.
I was proposing this based on "But it's stupid to have PV and Inverter perfectly functional during a sunny day and don't have power at home because the grid is down.", not for V2H.

Obviously, the thing to do would be mount the Sunny Boy on the house and plug a DC wire into the 'bolt

Be sure to look into capacitor precharge/inrush limiters before connecting a lithium battery to an inverter.

For some people, using their electric car as backup AC source for the house would be useful.

Another type of system would have a battery inverter wired as UPS for the house, and AC coupled PV inverters. The large vehicle battery could be connected to an AC coupled inverter with suitable configuration (not PV MPPT). Surge currents would come from battery inverter, which might have AGM battery. The vehicle battery could feed through a smaller 2.5 kW inverter, called upon to only put out enough to keep AGM floating.

Would want a control system to recharge car when PV surplus was available.
Maybe 60 Hz to 60.5 Hz, 'bolt inverter ramps down from 100% to 0%. 60.5 Hz to 61 Hz, 'bolt charger ramps up 0% to 100%. 61 Hz to 62 Hz, AC coupled PV ramps down 100% to 0%
 
7.7 kW Sunny Boy can be had for $1200 to $2000. Quite high?
No. You are right. A 7.7 kW SMA unit for 1500$ is super nice.
It's just sad there is no swith to turn this inverter from grid tie to off-grid and use it in my application.
 
SMA seems to have done that with Sunny Boy Storage, but designed for three 400V battery inputs rather than PV MPPT inputs.


Focusing on large markets, of course. There have been many grid-tie systems installed. Peak shaving is another applications, and Sunny Boy Storage can do that with both Sunny Boy and other brand grid-tie inverters. Actual backup system with transfer switch requires yet another box.

A hybrid that is batteries optional may do what you want. But since you're going to connect the 'bolt battery to PV input, you don't also get PV as a source and to recharge 'bolt battery. So I think a separate battery backup system at the house and a way to both draw from and charge vehicle would give the most complete system.
 
Yes, this seem the only interesting solution for my needs. I don't like the fan cooling system (prefer convection cooling) and I have reserve about quality.... but this seem the only interesting solution.

I also stumbled across these models as well which is 5.5kW, possibly based on similar design as the other one linked to above..


 
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Be sure to look into capacitor precharge/inrush limiters before connecting a lithium battery to an inverter.

My rule of zapped thumb, never work on 200V+ with out a contactor and pre-charge touch nothing. 48v tingels, 200v+ latches.
 
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