Can high grid voltage shut down inverter?

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mobo

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In a residential solar application, do inverters shut down if the grid voltage is too high? If so, what are the rules or parameters for this? Like, at what grid input voltage does the inverter shutdown? If so, is this a universal rule here in the U.S.? (I'm in Missouri)
 
Yes. The inverters have an operating voltage range. If the utility voltage spikes out of that range it will throw the inverters into a fault. Those values should be specified on the data sheet.

I believe the utilities standards are 5% and max 10%. Inverters usually have a high limit of 264V (Single phase 120/240V). Some you can log into and increase that limit.

Sent from my SM-G998U using Tapatalk
 
mobo said:
In a residential solar application, do inverters shut down if the grid voltage is too high? If so, what are the rules or parameters for this? Like, at what grid input voltage does the inverter shutdown? If so, is this a universal rule here in the U.S.? (I'm in Missouri)
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Assuming you are using UL compliant inverters then the voltage range is specified by UL1741. 264V is the typical default high limit for 240V service but some inverters can go as high as 288V.
 
often the grid voltage at the inverter is too high because of voltage rise (like voltage drop) because the grid voltage isn't going to get pushed down by a PV inverter sending power out to grid, the voltage at the inverter will actually rise instead with the same principal as voltage drop. So it could be a matter of upsizing your conductors if your utility wont allow for inverter settings to be modified to accommodate this.
SMA will give you a "grid guard code" to make changes so should be easy to fix that way
 
hansolar said:
SMA will give you a "grid guard code" to make changes so should be easy to fix that way
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if it's an SMA application maybe check in with SMA prior to using their grid guard code? if i remember correctly, you void the warranty on the inverter once you use it...at least that's my memory from a few years back...
 
ak1954 said:
if it's an SMA application maybe check in with SMA prior to using their grid guard code? if i remember correctly, you void the warranty on the inverter once you use it...at least that's my memory from a few years back...
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By all means check, but I do not think that's correct. What I'm pretty sure will void the warranty is if you subject the DC input to higher than the published maximum for the inverter; the inverter has an internal register where it records the highest DC voltage it has seen.
 
I have a question. With the Tesla power walls. Customer's incoming supply looses neutral in the service lateral . Will the Tesla wall inverter components fry up like the gfi outlets and smoke detectors inside the house can?
 
macmikeman said:
I have a question. With the Tesla power walls. Customer's incoming supply looses neutral in the service lateral . Will the Tesla wall inverter components fry up like the gfi outlets and smoke detectors inside the house can?
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No, Tesla PowerWalls provide their own neutral reference inside each unit. Not quite sure how (auto transformer or two synced 120V inverters?) but they do. In fact, no offgrid system is dependent on the utility neutral, they all have to do this somehow.

I would hope the Tesla gateway will see the open neutral as grid voltage being out-of-range and disconnect. Thus, not only would the Powerwalls themselves not fry, but hopefully anything connected to the backed up circuits won't either. (Now, anything that wasn't backed up would probably still fry...)
 
The Tesla PW will not connect to the grid if the voltage is out of range....not sure exactly what the range is but in the datasheet it show a number of input ranges,so I suppose it's adjustable or there are separate models for whatever your grid has. I don't know what ours is set for but I have a digital meter full-time on the grid and I've seen it above 260 sometimes and the Tesla will not connect to it at that point. I think the same strategy applies to low grid voltage...I'd guess below 210 or so it might not connect, but the data sheet doesn't show minimums. I'd guess we have the 230v model or setting. One of the real benefits of running on the Tesla is stable voltage. Our grid service is horrible. I've seen it float from full blackout to brownout to one phase dead to 265VAC at different times, and for no weather related reason,...perhaps a generator caught fire. And there are surges that will explode wall-plugged phone chargers, microwaves, TV's in a 'wait for remote' mode, etc...just a pile of burnt-out stuff thanks to the grid. We no longer have that and we don't have to unplug everything in the house if we're going out and there might be a lightning storm, very common here in summertime. These are just some of the 'comfort of life' benefits of going full solar.
 
caribconsult said:
And there are surges that will explode wall-plugged phone chargers, microwaves, TV's in a 'wait for remote' mode, etc...just a pile of burnt-out stuff thanks to the grid. We no longer have that and we don't have to unplug everything in the house if we're going out and there might be a lightning storm, very common here in summertime. These are just some of the 'comfort of life' benefits of going full solar.
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A PV+ESS system is not a surge arrestor. It will not disconnect the grid fast enough to prevent a lightning induced overvoltage from showing up in the building. Now there was probably a surge arrestor that came with the system that is helping with this. But if you were getting equipment fried by local lightning strikes you should have installed a whole house surge arrestor a long time ago.
 
wwhitney said:
The poster your responded to was referring to running off-grid, and is in a location with a pretty bad utility grid.

Cheers, Wayne
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My reading of it was that they are saying the system detects voltage surges and disconnects from the utility to protect their home. I don't see anywhere where it says it's it an off-grid system with no utility connection.

Cheers
 
pv_n00b said:
I don't see anywhere where it says it's it an off-grid system with no utility connection.
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He says "one of the real benefits of running on the Tesla is stable voltage" after referring to the unstable grid voltage. That implies he's running off-grid most of the time.

Plus he's said so in other threads. : - )

Cheers, Wayne
 
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wwhitney said:
He says "one of the real benefits of running on the Tesla is stable voltage" after referring to the unstable grid voltage. That implies he's running off-grid most of the time.

Plus he's said so in other threads. : - )

Cheers, Wayne
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Hey, Wayne, thanks for the support! I love it when I put a post up and someone totally does not read it thoroughly, and then two or three responses are needed to straighten it out. Yes, we are about 99.99 % off grid. Being in the tropics, there's plenty of sun, except once in a while, like today, it's gloomy and rainy out and the PV array is putting out between 1-2Kw. Probably not enough to fully charge the battery, so on a day like this, we'd open the grid breaker for an hour or two after sunset and get the battery up to the 90's. Costs perhaps $1.25. At no point did I say anything about the Tesla acting as a surge protector....it does protect us from surges in that we aren't connected to the grid, but surges here can come up the phone lines, the cable TV lines, you name it. An stable voltage is a big plus. Actually, the Tesla system will detect surges on the demand side and it doesn't like them. Our handyman was using his cheesebox welder here and the jolt from striking the spark shutdown the Tesla several times. It did restart, but at that point we switched the whole house to the grid while he was welding, and that was the end of that. Now we know to switch over for things like that. It's a learning process, managing a Tesla, but def worth it in terms of quiet, convenience and stability.
 
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