Inverter with Limiter

[oldsalty]

I installed 6 300 watt 24 volt panels and 2 grid tie inverters several years ago. Each bank of 3 are wired in parallel and connected to dedicated breakers on the right phase of the breaker box. Both banks also have disconnect switches. This system has run very well and has saved me several hundred dollars a year on my electric bill. However back in the later part of 2019 the utility company installed a smart meter and I noticed I was being charged for the power I was producing so I had to turn off my systems. I am aware of net metering BUT it will cost me SEVERAL THOUSAND BUCKS to do so. So I heard about inverters with limiters that block power from going to the grid. My question is, can I use 1 inverter and 1 current clamp since the dedicated breakers are on the the same phase in the breaker box?

Thanks

 

[mopat]

in the later part of 2019 the utility company installed a smart meter and I noticed I was being charged for the power I was producing

Wow! That seems a little bizarre. Can you share your zip code and name of your power company?

 

[oldsalty]

Maby I forgot to mention that my systems are not UL approved, so I can't use net metering since I installed it myself. I would need a solar meter, permits from the city, licenced contractor to install the system etc... It would cost me 20,000 bucks for all that that would NEVER be recovered.

 

[MisterSandals]

system has run very well and has saved me several hundred dollars a year on my electric bill.

and I noticed I was being charged for the power I was producing

This seems a bit contradictory too.

Is there even more to the story?

 

[Sunny Days]

From what ive read online any power sent to the grid WILL BE CHARGED as if it was consumed!
Only the old spinning disk meters stopped, any digital meter or smart meter will detect and count "up" any power sent to grid. This is probably what happened, then there are the Grid-tie meters or bi directional "net metering" which need permits and pro installation witch cost here over 20,000, they wont just put in a net metering meter, has to be the whole "package".

I was planning on instaling several gridtie inverters just to help with consumption but decided not since during the day while not home i would be charged for production and or contacted by the Power comp.

 

[Sunny Days]

I have 2 Grid tie inverters with limiters and havent installed them yet.
Aliexpres GTIL link
these are not UL listed, some youtube vids say they are great. I wonder who else makes anything similar?

 

[Ampster]

Two Grid Tie inverters that I know of can be programmed for non export. Those are Solaredge and Enphase. They both require consumption CTs for the programing to work.
Many hybrid inverters can also be programmed for non export.
@oldsalty , you would need to find out if your inverters can be programmed that way. What brand are they?

 

[Steve_S]

! PAUSE !

Your headed in the wrong direction ! You do NOT want Grid Tie Inverter here !
You will not be selling power to Big Power Co and trying to do so will cost you licensing, installation, certification etc... (per your locale).
You need an Inverter that watches the GRID-AC and can pull from it when IT needs it to charge your battery bank & to provide Pass-Through power while charging.

Basically:
Solar Panels to SCC to Batteries to Inverter to Home. When home get's low, Inverter enables charging "from the grid" and charges the batteries while passing power to the home at the same time. When Batteries are full Grid AC is disconnected and your back on 100% battery. This only requires ONE VAC Grid Line to the Inverter AC Input. This is the same method used as "Home UPS" and for those people doing TOU Shifting (Time of Use billing) where daytime rates are very high but nighttime rates are low. The Inverter is programmed to charge the batteries at night which are used during daytime to save costs.

There are several Inverter/Chargers which can accomplish this. I myself use a Samlex EVO-4024 which has dual AC Input, 1 for Grid AC with built-in ATS and programmable and 1 for GenSet AC with an AGS port (Auto-GenStart). I've programmed mine to take 120V/30A from my genset as I can push 24V/50A from the Charger to the battery bank.

This let's you use the grid as "backup" to your solar/battery system with only one 120V/20a to 120V/30A outlet to support the Inverter/Charger. It will not push power out as it is receiving only from the grid. You would not have to have this certified & approved for grid intertie. There is no need for a DISCO or other hardware as demanded by Grid Power Co's as it's not feeding back.

Please have a look at the Samlex EVO Inverter/Chargers and consider that route. These are Tier-1 products so not cheap BUT not outlandish like others, alternately you can explore Victron (a bit more but high end goodness)

See links in my signature as well as this link for the EVO-4024

4000 Watt 24V Pure Sine Inverter/Charger | EVO-4024 | Samlex America

4000 Watt 24V Pure Sine Wave Inverter/Charger with 110A Battery Charger + 70A Transfer Switch. Marine grade, heavy-duty power for rv, boat & off-grid.

www.samlexamerica.com

Good Luck, Have Fun.
Steve

 

[Ampster]

From what ive read online any power sent to the grid WILL BE CHARGED as if it was consumed!
Only the old spinning disk meters stopped, any digital meter or smart meter will detect and count "up" any power sent to grid.

Many power companies have different policies. I ran a Grid Tie inverter before I had my Permission to Operate and was never charged or credited for net power sent to the grid. I did have an application on file and the delays were beyond my control. I don't recommend doing that but just mentioning it to demonstrate that policies vary. I still don't understand how my GT inverters were turned on.

 

[Ampster]

Your headed in the wrong direction ! You do NOT want Grid Tie Inverter here !

@oldsalty
Steve is correct. I also have a hybrid inverter with batteries. It was expensive but long term worth the investment. If your existing inverter cannot be programed for non export you have limited options. You could invest in a grid tie inverter that can be programmed for non export. It most likely would be UL approved and you could then decide if you want to go through the hassle of applying for Net Metering. Or as Steve suggested and I have done, you could get a hybrid inverter and batteries. You technically would still need a building permit.

 

[oldsalty]

I have no desire for a whole house system nor EXPENSIVE battery banks that have to be REPLACED I'm told about every 3 years. I also have no room for batteries anyway. , I just want to SLOW the meter down. All I want to do is be able to use my panels like I did with the old meter. I found a Sun inverter with a limiter that uses a current clamp that keeps from back feeding excess power too the grid. I do appreciate all the reply's on this

 

[MisterSandals]

My understanding of how net metering works is different from what you describe. Its possible every utility is different but what Pacific Gas and Electric does (my utility) makes the most sense. I'm not happy with it but it makes sense.

My service panel has 2 meters inside it. One measures how much electricity I actually use in my house. I pay for all of this something like $.30 per kWh.
There is a 2nd meter that I cannot read that counts how much electricity my solar array produces. I get a credit for this of about $.15 (rough number here, there are MANY different rate depending on day/time...).

So the bill of course is undecipherable but I do get some credit for what i produce. What I like is that I can actually see the meter digital dial slow or actually spin back wards when i produce more than i am using. I cannot make heads or tails of the running total numbers visible but it seems to be about right.

I know i didn't really answer any questions but maybe it will help you understand what your meter is doing, or help you formulate questions to ask your utility.

 

[Ampster]

I have no desire for a whole house system nor EXPENSIVE battery banks that have to be REPLACED I'm told about every 3 years

It sounds like you found something that will work for you. Let us know how it goes and if you need any help figuring out where to place the current clamps.

 

[Ampster]

My understanding of how net metering works is different from what you describe. Its possible every utility is different but what Pacific Gas and Electric does (my utility) makes the most sense. I'm not happy with it but it makes sense.

Yes, there are utilities that have different rules. Recently there was a poster on another forum who had a home in Big Bear, California. His utility was a small coop that had a different rule. Their rule was similar to the OP's utility. They charged for export. What made that thread interesting that the OP had paid for an Enphase system that was supposed to be lrogrammed for no export. The installer did not know what he was doing and did not place the CTs in the correct place. As a result the system was exporting and when the OP got the bill he tried to get the problem solved but it took a while. That is why i advised @oldsalty to make sure he installed the CTs correctly.

 

[oldsalty]

This is the inverter I have on the way. SUN2000GTIL2W . I ordered 2 CT clamps (SCT013, 100amp/50ma), these will be installed on L1 and L2 main cables in the breaker panel with the arrow's facing the load. Since the inverter only has 1 internal limiter input I will SERIES both clamps. This inverter is programmable. I've converted my solar array from 24 volt to 48 Volt and rewired the outlet to 220 VAC. According to one guy on Youtube that has one of these setup I don't need to install a bleed resistor between the 2 clamps.Will let you all know how it turns out.
Again, Thanks so much for the help and comments on this.
_Kelly

 

[Ampster]

That sounds like it will work for you. If your L1 and L2 are small enough to fit through a single CT (current clamp) that might have worked also.

 

[BradSolar]

Is anyone else using one of the Sun 2000 GTIL2W inverters? Just looking for good/bad experiences...

 

[MisterSandals]

Is anyone else using one of the Sun 2000 GTIL2W inverters? Just looking for good/bad experiences...

I recommend starting a new thread with "Sun 2000 GTIL2W inverters" in the title to get better visibility than buried in this thread.

 

[oldsalty]

I just thought about something with ANY of these grid tie inverters that plug into a standard outlet. (BTW, I did get the Sun 2000 watt inverter/limiter but haven't started it up yet)

I have 8 awg wire connected to the DC input of the inverter from the solar panels, The AC output from the inverter is just a standard 16 awg plug like plugs into a computer power supply. How can such a small cord carry a load that can power the house? What am I missing here??

 

[Ampster]

How can such a small cord carry a load that can power the house? What am I missing here??

Perhaps your 120 volt inverter only puts out 10 Amps which would be okay for that AWG. I remember you never expected to have it power your whole house. However plugging it in is probably not to code since it is a permanent installation. Where are you going to put the CT current limiters? When you install them it might be a good idea to put that inverter in a separate circuit. At any rate, good luck wiith your project. Glad you found one that suits your purposes.
NOTE:
I reread the thread and saw that you were planning on rewiring an outlet to 240 volts. That changes the calculation because 2000 Watts divided by 240 volts is less than 10 Amps.