diy solar

diy solar

Recommended vendors for GTIL inverters?

hi fafrd,
are you still active here? i have a similar setup and love the GTI2 1000W with the current limiter to prevent back feeding to grid. i bought 3 100Ah 12V litime batteries to capture the solar energy otherwise lost during the day and want to run the GTI in battery mode in the evening. i bought 3 to get to 36V which i think is needed for the GTI. it seems you run it with 24V only - does that work or you added a DC-DC stepup (which i do not while i use only 1 12V battery). i have a tough time to find a proper controller with BT or wifi and battery charge current limit settings. is your system still running? my solar side is 5x100 newpowa panels. would yo have a wire diagram of your setup please? thanks erhard
I can assist u. I am the moderator of the Facebook group regarding these inverter. 36v is much better than 24v. 24v is at the lowest operating voltage of the GTIL2. That makes the inverter constantly have to use more amps than it woulld with a 36v battery which causes the inverter to work harder, which would shorten its life. I use two of the 2kw versions powered by a 60v battery for my split phase home, and have been 4 years. The inverters cover almost all of my homes power usage 24/7... I just let them run. I use an Outback fm80 charge controller. They make a cheaper fm60. It doesn’t have BT or wifi. Midnite chargecontrollers is one that has that capability.
 
I can assist u. I am the moderator of the Facebook group regarding these inverter. 36v is much better than 24v. 24v is at the lowest operating voltage of the GTIL2. That makes the inverter constantly have to use more amps than it woulld with a 36v battery which causes the inverter to work harder, which would shorten its life. I use two of the 2kw versions powered by a 60v battery for my split phase home, and have been 4 years. The inverters cover almost all of my homes power usage 24/7... I just let them run. I use an Outback fm80 charge controller. They make a cheaper fm60. It doesn’t have BT or wifi. Midnite chargecontrollers is one that has that capability.
thanks so much for your help. i am not a FB member so i rely on this forum. what you say makes full sense to me. currently i run it of 12V because i only had 1 battery but i use a DC DC step up to 50V to the GTI and that works but quite inefficient. 280W PV outputs 200W to the house. i know the GTI is about 88-90% so the DC-DC is only about 80%, not good in the long run. i have tried now 3 controllers 2 bougeRV ,1 LITIME (60A). the bougeRV 40A with BT was actually great but can only do 12/24V, the litime 60A was disappointing because it has very little parameter control and no charge current limit, so i will look at yours.
question why did you go for 2 110V rather than use the 240V ? do you have the current limiter install to avoid back feeding ( i do). would you be able to share your schematic for the setup. ideally i would like to switch to battery with a timer at 4pm when peak starts.
thanks
erhard
 
question why did you go for 2 110V rather than use the 240V ?
The 2kw inverters are 240v.
do you have the current limiter install to avoid back feeding
Yep, 2 CTs spliced together to read my homes splitphase loads. I’m in the USA.
would you be able to share your schematic for the setup
It’s easy I’ll share a pic of how it‘s wired. Solar to chargecontroller to batteries to inverters
ideally i would like to switch to battery with a timer at 4pm when peak starts.
I have 18kwh DIY LIFEPO4 battery that covers most of my homes loads 24/7. There really isn’t much of a day time load for most homes so Solar direct usually covers that and the excess charges the battery. Then in the evening the battery takes over when there isn’t enough solar
 
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thanks.
looks like a great setup. i am in the other extreme. i have only a patio area for panels so 600W total is all i get with lots of shadow in the morning and evening. so 3x100Ah 12V batteries coudl be charged during day and then i use them later in the evening during peak time. better than nothing.
the GTI2 100W has AC from 100 to 240V auto detection. currently i only use 110V.
thanks for sharing. i am in CA, san jose.

update:
here is what i want to try.
1. the GTI DCin is connected to the battery (36V)
2. i will use a simple 110V outlet timer, like for xmas lights, and start it to connect the outlet to the AC out of the GTI at 4pm (peak time) till morning 6am.
3. i also will need to set the low voltage shutoff at the GTI to maybe 3x11V=33V. so it will not deplete the battery completely.
4. in the morning when sun comes up the GTI is still off and the battery can be solar charged. no other load active on the battery.
i hope that works

one thing i am wondering.
if at (1) i connect instead the GTI to the DC LOAD output of the MPPT charge controller i could operate the GTI through the controller. however, rarely the controllers to have timer relays so that would only work through battery voltage which is not so ideal.
 
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thanks.
looks like a great setup. i am in the other extreme. i have only a patio area for panels so 600W total is all i get with lots of shadow in the morning and evening. so 3x100Ah 12V batteries coudl be charged during day and then i use them later in the evening during peak time. better than nothing.
the GTI2 100W has AC from 100 to 240V auto detection. currently i only use 110V.
thanks for sharing. i am in CA, san jose.

update:
here is what i want to try.
1. the GTI DCin is connected to the battery (36V)
2. i will use a simple 110V outlet timer, like for xmas lights, and start it to connect the outlet to the AC out of the GTI at 4pm (peak time) till morning 6am.
3. i also will need to set the low voltage shutoff at the GTI to maybe 3x11V=33V. so it will not deplete the battery completely.
4. in the morning when sun comes up the GTI is still off and the battery can be solar charged. no other load active on the battery.
i hope that works

one thing i am wondering.
if at (1) i connect instead the GTI to the DC LOAD output of the MPPT charge controller i could operate the GTI through the controller. however, rarely the controllers to have timer relays so that would only work through battery voltage which is not so ideal.
They now sell GTIL2 that are a white color that have time of use functionality built in. Havnt seen any being used in the USA. But they are sold over sees somewhere
 
if at (1) i connect instead the GTI to the DC LOAD output of the MPPT charge controller i could operate the GTI through the controller. however, rarely the controllers to have timer relays so that would only work through battery voltage which is not so ideal.
I’d only connect theses inverters to the battery or directly to solar to avoid damaging them
 
thanks.
looks like a great setup. i am in the other extreme. i have only a patio area for panels so 600W total is all i get with lots of shadow in the morning and evening. so 3x100Ah 12V batteries coudl be charged during day and then i use them later in the evening during peak time. better than nothing.
the GTI2 100W has AC from 100 to 240V auto detection. currently i only use 110V.
thanks for sharing. i am in CA, san jose.

update:
here is what i want to try.
1. the GTI DCin is connected to the battery (36V)
2. i will use a simple 110V outlet timer, like for xmas lights, and start it to connect the outlet to the AC out of the GTI at 4pm (peak time) till morning 6am.
3. i also will need to set the low voltage shutoff at the GTI to maybe 3x11V=33V. so it will not deplete the battery completely.
4. in the morning when sun comes up the GTI is still off and the battery can be solar charged. no other load active on the battery.
i hope that works

one thing i am wondering.
if at (1) i connect instead the GTI to the DC LOAD output of the MPPT charge controller i could operate the GTI through the controller. however, rarely the controllers to have timer relays so that would only work through battery voltage which is not so ideal.
The name of the GTIL2s with TOU is Lumentree
 
I can assist u. I am the moderator of the Facebook group regarding these inverter. 36v is much better than 24v. 24v is at the lowest operating voltage of the GTIL2. That makes the inverter constantly have to use more amps than it woulld with a 36v battery which causes the inverter to work harder, which would shorten its life. I use two of the 2kw versions powered by a 60v battery for my split phase home, and have been 4 years. The inverters cover almost all of my homes power usage 24/7... I just let them run. I use an Outback fm80 charge controller. They make a cheaper fm60. It doesn’t have BT or wifi. Midnite chargecontrollers is one that has that capability.
Sorry to barge in with a different question, but do you know if it is possible to use these inverters in conjunction with a standard grid tie inverter on the same circuit? I assume they would need to shut down to avoid an islanding scenario, in the event of loss of the grid.
 
Sorry to barge in with a different question, but do you know if it is possible to use these inverters in conjunction with a standard grid tie inverter on the same circuit? I assume they would need to shut down to avoid an islanding scenario, in the event of loss of the grid.
Can’t see why not. Have heard of many adding them to their grid tie setup. The GTIL2 would need its own solar panels.
 
Can’t see why not. Have heard of many adding them to their grid tie setup. The GTIL2 would need its own solar panels.
Thank you, Ill be adding some extra panels soon so that wont be a problem. It seems to be such a flexible inverter.
 
Sorry to barge in with a different question, but do you know if it is possible to use these inverters in conjunction with a standard grid tie inverter on the same circuit? I assume they would need to shut down to avoid an islanding scenario, in the event of loss of the grid.
That is exactly how I am using them.

I made a modified double CT cable so each GTIL can monitor import power - grid-tied solar power generated by my 4kW grid-tied array.

Each GTIL senses consumption net of solar production on one 120VAC leg and offsets that so my export power = my 4kW array full solar production over peak hours after 4pm…
 
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I can assist u. I am the moderator of the Facebook group regarding these inverter. 36v is much better than 24v. 24v is at the lowest operating voltage of the GTIL2. That makes the inverter constantly have to use more amps than it woulld with a 36v battery which causes the inverter to work harder, which would shorten its life.

Glad to see you here as I don’t use Facebook either.

My main concern has been the failures over time reported with these GTIL’s.

From what you have said I assume for use directly with a 48V nominal LiFePO4 battery (not solar panels) the lower voltage range one would be best ?

Edit: To be more specific, the 25-60V one would be better suited for a 48V nominal LFP than the 50-90V one correct?
 
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Glad to see you here as I don’t use Facebook either.

My main concern has been the failures over time reported with these GTIL’s.

From what you have said I assume for use directly with a 48V nominal LiFePO4 battery (not solar panels) the lower voltage range one would be best ?

Edit: To be more specific, the 25-60V one would be better suited for a 48V nominal LFP than the 50-90V one correct?
Correct. It’s the same with any inverter. If using a battery voltage near the inverters lowest usable voltage it will work the inverter harder. It matters with these inverters more so because of their wide battery operating voltage range. The best voltage batteries for each voltage range is a 36v and a 72v, but most don’t use those voltages. Reason those are the best,,, it’s not at the higher end of either inverters operating voltage. Being at the higher end could push the inverters parts to failure. Being at the lower end pushes the inverters to hard. I use a 19s (roughly 60v nominal) Lifepo4 battery for two of the 2kw 45-90v inverters. I have seen many failures from users using a 24v battery for the lower operating voltage and a 48v battery for the higher operating voltage
 
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Glad to see you here as I don’t use Facebook either.

My main concern has been the failures over time reported with these GTIL’s.

From what you have said I assume for use directly with a 48V nominal LiFePO4 battery (not solar panels) the lower voltage range one would be best ?

Edit: To be more specific, the 25-60V one would be better suited for a 48V nominal LFP than the 50-90V one correct?
The one thing I learned from painful experience is that these GTILs are very susceptible to damage when BMS protection kicks in.

It’s right to there in the manual but I did not properly understand the implications: ‘always disconnect AC before disconnecting DC. Failure to do so can result in electrical damage to your inverter.’

My BMS low voltage disconnect protection kicked in only one in 3 years but the result was stinky smoke and a fried GTIL.

So if using these inverters, it’s very important to assure the inverter hits it’s battery-level low voltage disconnect before any cell in the battery can discharge below BMS low voltage disconnect level (meaning the battery needs to be well-balanced near the lower knee…).

Battery was getting down near disconnect voltage, large load turned on causing GTIL to surge to near max output causing battery current to surge causing lowest SOC cell to drop below BMS LVD of 2.5V causing BMS to abruptly shut off battery causing GTIL to fry.

Make sure BMS protection can never kick in while one of these GTIL inverters is generating AC power (again, it’s right there in the manual).
 
The one thing I learned from painful experience is that these GTILs are very susceptible to damage when BMS protection kicks in.

Make sure BMS protection can never kick in while one of these GTIL inverters is generating AC power (again, it’s right there in the manual).

Thanks to both of you.

One last question (I hope).

Can I set both a global limit and a CT based limit- at the same time.

Say I never want it to produce more than 700 Watts in hopes of extending the longevity and at the same time I want to current limit via the CT so there is no exporting if the load drops below 700 Watts …..

I should be able to set both limits at the same time right ?
 

don’t know why this is acting like it’s your quote… this isn’t fafrd quote. This is mine
When the inverters under load its absolutely best to turn off the actual AC loads before turning off the inverters AC or DC breakers. If the inverter isn’t powering any loads then turning off AC or DC shouldn’t matter. I choose to turn off DC first as long as the inverter isn’t under load. The inverter simply goes into DC voltage to low mode. These inverters commonly (sometimes everyday) automatically go into DC voltage to low mode. Rarely would these inverters shut off its own AC first. It would only happen to prevent islanding which would be a rarity. I certainly don’t like the idea off cutting off the AC breaker when the inverter is under heavy load. If the inverter is under heavy load and the AC path is instantly cut off then there’s nowhere for the generated DC power to go. That seems like a possibility for smoke. Either way I’d say never turn off the AC or DC breakers under load.
The manual says to never disconnect the DC while the AC is on. IMO they are saying do not physically remove the DC wires while the inverters AC is connected to prevent injury to yourself. But it’s not worded that way due to a language barrier..
 
Thanks to both of you.

One last question (I hope).

Can I set both a global limit and a CT based limit- at the same time.

Say I never want it to produce more than 700 Watts in hopes of extending the longevity and at the same time I want to current limit via the CT so there is no exporting if the load drops below 700 Watts …..

I should be able to set both limits at the same time right ?
Yep, you would simply select internal limiter in settings. That prevents export. Then also set an amp in the settings. When using a battery it’s better to use the amp limit than to use the watt limit settings. There’s a setting for each. The watt limit setting should only be used if the inverter was only using solar panels without a battery.
 
Thanks to both of you.

One last question (I hope).

Can I set both a global limit and a CT based limit- at the same time.

Say I never want it to produce more than 700 Watts in hopes of extending the longevity and at the same time I want to current limit via the CT so there is no exporting if the load drops below 700 Watts …..

I should be able to set both limits at the same time right ?
Yes, after frying my GTIL because it surged to a full 1000W output while battery was just over LVD limit, I now limit to 150% of my average output level (450W in my case).

I really don’t need the GTIL to offset consumption surges - offsetting average consumption delivers 99% of the value and is safer (easier on the inverter and as well as the battery).
 
I really don’t need the GTIL to offset consumption surges - offsetting average consumption delivers 99% of the value and is safer (easier on the inverter and as well as the battery).

My use is a bit different. I have moved many loads over to my critical loads panel and that is all my system can handle in the winter. It's a different case in the summer when I generate more power.

So I want to use a GTIL to offset loads in the main house panel whenever I have excess generation, however, I need to avoid exporting to the grid since I don't have an agreement with my power company to do so and do not want one.

Since I will feed the GTIL directly from my 48V nominal battery bank I will not have to disturb what I have set up there with SCC's etc. nor will I need to change anything with my critical loads panel.
 
They now sell GTIL2 that are a white color that have time of use functionality built in. Havnt seen any being used in the USA. But they are sold over sees somewhere
ok the GTI2 SUN 1000W i ordered 6 weeks ago is blue and also has the scheduling feature built-in
 
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