How to use 220V hybrid MPPT controller to run both 110V and 220V appliances

[Jeff From NJ]

I'm in the U.S. and looking at picking up a hybrid MPPT controller and trying to figure out if I should get a 110V output or a 220V output (60Hz). The plan is to hang a subpannel off the main breaker and connect a few necessary appliances to the subpanel to be powered by solar in case of grid down.

Can I get a 220V output controller and power the subpannel with the 220V, using 110V where needed and 220V where needed, or do I need to get some sort of device to step down the 220V for all the breakers that will power 110V appliances and wire the 220V directly to the two breakers that will power the two appliances that require 220V?

Thanks all!

 

[BentleyJ]

Based on your terminology, its not completely clear what you are asking. I believe that you are referring to is a HYBRID INVERTER that includes a built-in MPPT charge controller. In that case, you would have several very good options for a split-phase 240V system that would operate a subpanel. Beware there are many variations. For example, MPP solar offers 120V hybrid inverters that are capable of split phase 240V operation BUT you would need to stack 2 of them. They also have single inverters that output 240V. Other manufacturers have 240V, 60Hz models for the US but they may NOT have an internal Neutral so you would have to add a center tap transformer so your subpanel would have 120V. Dave Poz covered this subject very well. You mentioned 2 appliances that require 240V, generally that implies they are high power usage items like a Range or AC or Well Pump. In those cases you would want to look at a low frequency Inverter vs. a high frequency inverter. I would start by browsing the MPP Solar website. Lastly, if you plan to power a subpanel with both grid power and an inverter you will need a manual or automatic transfer switch so the subpanel does not feed into the grid when it goes down. Alternatively, the higher end Hybrid Inverters have a built in ATS.

 

[Jeff From NJ]

I am indeed speaking of a Hybrid Inverter with MPPT charge controller (all in one). I am not looking to parallel stack these and would prefer to buy a single unit that is able to power the 240V since my panels will not increase in the future.

The idea of getting one that outputs 240V but also has an internal neutral seems to make sense, is there a "buzz word" that would alert me while reviewing units to this internal neutral (I know many of the Chinese manufacturers are not clear in their ads what their units actually offer). I am going to look at Dave's videos now to see if he is offering some info regarding this.

The plan would be to run some lights, a TV, a washing machine (110v) and dryer (220v) and a few refrigerators and freezers.

 

[BentleyJ]

The dryer is going to be the energy hog, Typically they can pull as much as 4 to 5KW. The electrical specs should be on a tag somewhere on the dryer. Take a look at MPPSolar.com and check out the LV6548. In the downloads section of the website you can browse thru the user manual.
Also, take a look at SunGold Power.com they do offer some split phase models in the larger sizes. The user manuals are available to browse or download. Just make sure whatever model you choose that it has L1, L2 and Neutral outputs.

 

[Jeff From NJ]

Just make sure whatever model you choose that it has L1, L2 and Neutral outputs.

Is this the key then? Make sure the outputs have 3 connections rather than just 2 since I think many Chinese writeups are not going to be clear regarding this?

 

[MisterSandals]

Just make sure whatever model you choose that it has L1, L2 and Neutral outputs.

This is good advice for simplicity. But the neutral can also be created from L1 and L2 with an autotransformer (an autotransformer that is not natively inside your AIO).

 

[BentleyJ]

Yes, the 3 outputs is what gives you the combination of 240V between the L1 & L2 outputs and 2 x 120V between L1 & N and L2 & N. Its also worth mentioning that a split phase Inverter is actually 2 separate smaller inverters operating 180 degrees out of phase with each other. This is important because an Inverter rated at 5,000W, 120/240V split phase is only going to deliver 2,500W from L1 & N and 2,500W from L2 & N. So for example if the dryer is running at 4,000W you only have 1,000W available for everything else BUT that 1,000 has to be divided up equally.

 

[MisterSandals]

a split phase Inverter is actually 2 separate smaller inverters operating 180 degrees out of phase with each other.

So are the 2 different ways to create 240V split phase?
1) with 2 different 120V inverters combined out of phase
2) with a 240V single phase inverter that creates L1 & L2 and an autotransformer that creates N?

 

[Jeff From NJ]

I found this device that says it is 48VDC 120VAC 240VAC 4000w 5000w 6000w off grid hybrid split phase solar inverter. Looking at the unit, I only see two output connections, looks like L & N. Does this mean it has 2 different 120V inverters combined out of phase then?

 

[BentleyJ]

There is not enough information to say for sure. It sounds more like a general description that may cover several available models. It is necessary to review either a detailed specification sheet or user manual for the particular model in question. Sounds like you are shopping based on price only, beware this can be a dangerous practice.

 

[Jeff From NJ]

The item has several options to choose from, and also several variations selected from within a menu. I'm not shopping based on price at all, I'm trying to understandf how to choose the correct unit from the hundreds of available choices and once I get a good understanding, will be able to begin selecting the correct unit at that point. The output is the one area I am having an issue understanding since so many of these units are sold worldwide and our US standards are not followed. I don't want to buy something that won't work in the US without some alterations.

 

[BentleyJ]

I completely understand, many of us have gone through this frustration and learning curve. There is probably no actual short cuts. I remember reading hundreds of pages of user manuals from Outback, Magnum, Schneider Etc Etc. when I wanted to install an AC coupled back-up system. Trying to get into the details of the user menu options and set up, its tedious. This forum is a very good source of information but ultimately you will be the one who has to choose wisely.

 

[Jeff From NJ]

Just for completness, here is the specs of the item I mentioned above:

Model: MPPT	0.3-1KW	1.5-6KW
power rating(w)	300	700	1500	3000	5000
500	1000	2000	4000	6000
Battery	rated voltage(VDC)	12/24	12/24/48	24/48	48/96
Charge Current	10A MAX	30A MAX
Battery Type	Can be set
Input	Voltage Range	170-275VAC
frequency	45-65Hz
Output	Voltage Range	110VAC/220VAC; ±5%( Inverter mode)
frequency	50/60Hz±1%( Inverter mode)
Output wave	Pure Sine Wave
Change time	＜10ms(Typical load)
Efficiency	＞85%（80% Resistive load）
overload	110-120%/30S；＞160%/300ms；
Protection function	Battery over-voltage and low-voltage protection, overload protection, short circuit protection, over-temperature protection
Solar Controller	MPPT Voltage Range	12VDC:15V~150VDC;24VDC:30V~150VDC;48VDC:60V~150VDC；120V~150VDC
PV Power	12VDC-30A(400W); 24VDC-30A(800W)	12VDC-60A(800W); 24VDC-60A(1600W); 48VDC-60A(3200W) 96VDC-60A（6400W）
Rated charge current	30A(Max)	60A(Max)
MPPT efficiency	≥99%
Average charging voltage(lead acid battery	12V/14.2VDC;24V/28.4VDC;48V/56.8VDC
Floating charge voltage	12V/13.75VDC;24V/27.5VDC;48V/55VDC
Operating ambient temperature	-15-+50℃
Storage ambient temperature	-20 - +50℃

 

[BentleyJ]

It seems like that product MAY work for you but based on those specs its not clear if this is a split phase inverter with 3 terminals. Also, the DC input voltage is limited to to 150VDC which reduces your flexibility in designing the solar wiring series vs. parallel. My advice would be to look at MPP Solar and SunGold as first choices and if for some reason they don't have a feature you really need then move on to the other LESS known brands.

 

[Jeff From NJ]

I'll check them out tonight, Thanks

There appears to be only 2 terminals on this unit:

 

[Jeff From NJ]

It seems like that product MAY work for you but based on those specs its not clear if this is a split phase inverter with 3 terminals. Also, the DC input voltage is limited to to 150VDC which reduces your flexibility in designing the solar wiring series vs. parallel. My advice would be to look at MPP Solar and SunGold as first choices and if for some reason they don't have a feature you really need then move on to the other LESS known brands.

I checked out MPP Solar and SunGold. I'm finding that their units are "split phase" if you parallel two units together, otherwise I only get 110V. Since I am not looking to buy two units today, just dipping my toe, I think I will need to live with 110V for now and wire the sub panel accordingly. I am now leaning towards the Growatt 3000TL 24p which seems to have everything I want (although only 110V if I only buy one unit - it comes with the parallel connector included however).

Can I add a second unit later and take the two 110V units and combine them to get 220V so I could power the bigger applainces?

 

[BentleyJ]

Yes, the smaller Inverters are 120V unless 2 are stacked. I was thinking more along the lines of the LV6548 because of the Dryer load you mentioned. Whatever system you ultimately choose to build has to be comfortable for you.

 

[Jeff From NJ]

The LV6548 ($1575) is double the price of the Growatt 3000TL LVM ($712) so I think I will go that direction and add a second 3000TL later once I get comfortable with the entire build and its operation.

That said, I will power a sub pannel off the main breaker connected to the 3000TL and just put 120V items in the sub panel for now.

 

[BentleyJ]

Excellent, please post some pics when you get the system installed and operating.

 

[Jeff From NJ]

Excellent, please post some pics when you get the system installed and operating.

Thank you very much for your guidance, and the others that chimed in here or on a different post I made. I will UL photos once things are built