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DEYE Inverter UL Listed available in US

And even if the meter only measures/reads kWh based on 240V, that doesn’t mean it can’t also recognize a fault situation based on L1 vs L2 consumption to set/issue a flag.
Why would any utility care what happens at that level of detail? I would not call a slight imbalance between legs a fault. Yes, anything is possible so I suppose it is better to be safe than sorry.
 
But I’ve read about GTIL customers operating at 240V to offset split-phase consumption having the export imbalance be flagged by the meter so that the utility came out to inspect and nabbed them.
I would love to see where you read that so I can become better informed. Are these examples of NEM 1.0 customers being bumped to NEM 2.0 or non NEM customers inadvertently exporting power? When you say "nabbed" what exactly happened?
 
Why would any utility care what happens at that level of detail? I would not call a slight imbalance between legs a fault. Yes, anything is possible so I suppose it is better to be safe than sorry.
For sure, if they’ve got any fault/imbalance detector built into their smart meters, they are going to set the threshold to flag a fault condition high enough to avoid nuisance trips.

But I don’t want to be the guinea pig on that. They can for sure have the meter flag any export on homes that have not been approved for net metering, so it’s really just a question of whether there is any hot-to-neutral/ground sending designed into the hardware or not.

It’s true that just sensing 240V current using a single CT sensor would be cheaper than any alternative solution based on 2 CT sensors, so there is that… (the almighty buck).
 
I would love to see where you read that so I can become better informed. Are these examples of NEM 1.0 customers being bumped to NEM 2.0 or non NEM customers inadvertently exporting power? When you say "nabbed" what exactly happened?
For sure I read about some early GTIL customers wiring things up wrong and triggering a visit from their electric company.

Not certain I’ve read about any NEM customers actually getting busted though I know I read about several being concerned about the issue.

That was almost a year ago now when these GTIL2 inverters were first hitting the market.

Maybe we should start a thread to see how many GTIL customers we have here in the Forum and used in which configuration…
 
For sure I read about some early GTIL customers wiring things up wrong and triggering a visit from their electric company.
And what was the consequence of that visit? Was it PG&E? I have had systems on both PG&E and SCE exporting before a PTO was issued and never got a visit or question. So it is not a risk that I am concerned about. I am not recommend that practice. I am just asking for facts not assumptions in order to understand the risk.
 
My meter has 3 wires into it, L1, L2, and ground/neutral from the pole.

The meter only sends L1 and L2 on to get main breaker, where a new neutral is bonded to house ground, but the meter can easily detect one leg expiring while the second leg is consuming by comparing to pole neutral/ground.

And even if the meter only measures/reads kWh based on 240V, that doesn’t mean it can’t also recognize a fault situation based on L1 vs L2 consumption to set/issue a flag.
Your meter (most likely) just lets the neutral (center tap of transformer) pass thru the meter.. the meter doesn’t not use neutral at all.. there would not be any fault ifbthe inverter isn’t supplying anymore power at 240v than the entire home is using
 
My meter has 3 wires into it, L1, L2, and ground/neutral from the pole.

The meter only sends L1 and L2 on to get main breaker, where a new neutral is bonded to house ground, but the meter can easily detect one leg expiring while the second leg is consuming by comparing to pole neutral/ground.

And even if the meter only measures/reads kWh based on 240V, that doesn’t mean it can’t also recognize a fault situation based on L1 vs L2 consumption to set/issue a
Is there any place to check smart meter design based on model (or electric utility). If my smart meter only uses a single CT sensor, that would simplify things a great deal, but I have enough riding on it that I’d want to be certain..,

Making a 240V GTIL2 offset splitphase 110 & 240V consumption is not the question - I know that can be done and that the meter will properly read 0kW consumed even if L1 is exporting an equal current to what L2 is consuming.

And I understand that if the smart meter only see see through a single CT sensor, that there is no way it can detect (or flag) that imbalance.

But I’ve read about GTIL customers operating at 240V to offset split-phase consumption having the export imbalance be flagged by the meter so that the utility came out to inspect and nabbed them.

Which is why I’m interested in any means to validate the precise sensing capability of my smart meter…

As I stated earlier, my smart meter receives ground/neutral from the pole/grid along with L1 and L2…
You can check your meter for the single CT thru a small opening in the side of your meter. Use a flashlight. The Ct is copper color in the middle of the meter. I’ve installed many meter bases. The neutral just passes thru with no connection to the meter itself
 
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For sure, if they’ve got any fault/imbalance detector built into their smart meters, they are going to set the threshold to flag a fault condition high enough to avoid nuisance trips.

But I don’t want to be the guinea pig on that. They can for sure have the meter flag any export on homes that have not been approved for net metering, so it’s really just a question of whether there is any hot-to-neutral/ground sending designed into the hardware or not.

It’s true that just sensing 240V current using a single CT sensor would be cheaper than any alternative solution based on 2 CT sensors, so there is that… (the almighty buck).
Using a single sensor on a splitphase panel will not allow the inverter to produce all of the power the home is using. The GTIL2s need 2 sensors one on each mains) wired together if supplying 240v from them
 
Using a single sensor on a splitphase panel will not allow the inverter to produce all of the power the home is using. The GTIL2s need 2 sensors one on each mains) wired together if supplying 240v from them
I thought we were talking about the meter, not the GTIL inverter.

Yes, I understand that using a 240V GTIL inverter to offset 240V split-phase consumption requires the use of two CT sensors wired in parallel…
 
You can check your meter for the single CT thru a small opening in the side of your meter. Use a flashlight. The Ct is copper color in the middle of the meter. I’ve installed many meter bases. The neutral just passes thru with no connection to the meter itself
Well first, thanks for that - I’d never noticed the two small clear ‘windows’ on either side of my smart meter before.

But secondly, on one side the window stops where the electronic board is, so I can’t see back to where the wires are, and on the other side, while the electronic board has a notch so that I can see a bit behind it, I can’t make anything out clearly enough to identify the L1/L2 wires, let alone a CT sensor.

My smart meter is a ‘Focus AXR-SD’ made by ‘Landis + Gyr’.

Does that help identify it in a manner that I might find a schematic or a teardown?

The fact you’ve actually installed many meters gives me a great deal more respect for your opinion on this subject that what I’ve read on the internet. Can I ask what part of the country you performed those installs?

And also, is it the electrician that installs the mains wires from house hookup to meter including the CT sensor and the utility just installs the electronics board and the meter housing?
 
Well first, thanks for that - I’d never noticed the two small clear ‘windows’ on either side of my smart meter before.

But secondly, on one side the window stops where the electronic board is, so I can’t see back to where the wires are, and on the other side, while the electronic board has a notch so that I can see a bit behind it, I can’t make anything out clearly enough to identify the L1/L2 wires, let alone a CT sensor.

My smart meter is a ‘Focus AXR-SD’ made by ‘Landis + Gyr’.

Does that help identify it in a manner that I might find a schematic or a teardown?

The fact you’ve actually installed many meters gives me a great deal more respect for your opinion on this subject that what I’ve read on the internet. Can I ask what part of the country you performed those installs?

And also, is it the electrician that installs the mains wires from house hookup to meter including the CT sensor and the utility just installs the electronics board and the meter housing?

In that pic the Ct can be seen. It’s actually 2 metal bars (one for each leg) that go thru the CT.
I would install the main panel and the mains wires from that panel to the meter base. Then from the meter bass I install the wires going out the weather head. The electric company attaches their wires to the wires coming out the weather head. In the meter base the wires from the main panel come into the meter base and are put into lugs. The wires from the meter base to the weather head are also put into lugs.. the meter itself (not the meter base) is what connects all 4 of those lugs and it is installed by the electric company. The meter is what has the CT in it. I’ve installed roughly 10 meter bases from the Mississippi to the east coast. I have heard of meters that have 2 CTs in them. But usually it’s just one Ct
 

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It’s actually 2 metal bars (one for each leg) that go thru the CT.
That looks like my PG&E meter. If it indeed has L1 and L2 going through one CT there is no way they could detect export on one leg and import on the other. The only thing that would be reported would be the sum of the two. Thanks for the clarification.
 
In that pic the Ct can be seen. It’s actually 2 metal bars (one for each leg) that go thru the CT.
I would install the main panel and the mains wires from that panel to the meter base. Then from the meter bass I install the wires going out the weather head. The electric company attaches their wires to the wires coming out the weather head. In the meter base the wires from the main panel come into the meter base and are put into lugs. The wires from the meter base to the weather head are also put into lugs.. the meter itself (not the meter base) is what connects all 4 of those lugs and it is installed by the electric company. The meter is what has the CT in it. I’ve installed roughly 10 meter bases from the Mississippi to the east coast. I have heard of meters that have 2 CTs in them. But usually it’s just one Ct
Thanks for all of the fantastic detail. I’m going to go out and have another look tomorrow - do you think it’s easier at night or during the day to see the CT sensor?

From what you’ve described, it sounds like the CT sensor is on the outside of the electronics board and looking in the window on the ‘notch’ side, I see something similar but I have to admit I’m confused about what I’m looking for in that picture you attached - anyway you could mark it in windows ‘paint’ of whatever to make the ‘two metal bars’ clear?

Have you ever seen an equivalent picture from a smart meter with 2 CT sensors?
 
Thanks for all of the fantastic detail. I’m going to go out and have another look tomorrow - do you think it’s easier at night or during the day to see the CT sensor?

From what you’ve described, it sounds like the CT sensor is on the outside of the electronics board and looking in the window on the ‘notch’ side, I see something similar but I have to admit I’m confused about what I’m looking for in that picture you attached - anyway you could mark it in windows ‘paint’ of whatever to make the ‘two metal bars’ clear?

Have you ever seen an equivalent picture from a smart meter with 2 CT sensors?
We might be going off topic. Sorry for that. I’ll try to keep the responses short. Blue is the metal bars/legs. Yellow is the Ct
 

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Most meters installed on residential splitphase homes have only one ct in them. Both mains wires/legs go thru this one Ct in opposite direction of each other. This is why the 240v GTIL2 output can be used on a splitphase power supply from electric company and there’s no backfeed detected. and it works very well

You mean, if the utility loses power on one phase (and other houses pull voltage to near zero), I can draw all the current I want from the still-live phase without cost, so long as I return equal current on the dead phase? :devilish:
 
You mean, if the utility loses power on one phase (and other houses pull voltage to near zero), I can draw all the current I want from the still-live phase without cost, so long as I return equal current on the dead phase?
How would you return current on the dead leg? The only way to lose power on a leg is if the connection at the transforner was lost for that leg. That would make an open connection in which no current would flow,
 
How would you return current on the dead leg? The only way to lose power on a leg is if the connection at the transforner was lost for that leg. That would make an open connection in which no current would flow,

Consider transformer on a pole near me, feeding several houses. L1 comes loose, but L2 and N remain connected.
The other houses with their lights, heaters, refrigerators that are 120V provide a low impedance path from L1 to N.

If I connected a load between L1 and L2, current would sum in the CT and be registered.
If I use two isolated windings of a transformer, one carrying current from L2 to my 120V loads (and back through N), connect other winding between N and L1, for every amp I draw it will suck an amp from L1 in-phase with L2 (rather than 180 degrees out of phase) and shove it into N.
The meter's CT registers zero.

Problem with the meter is it doesn't register power through each phase, only sums the current assuming voltages are equal.
 
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