are panels safe when just sitting on a roof turned off

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Re: are panels safe when just sitting on a roof turned off

Postby Gordon-Loomberah » Mon Apr 30, 2018 11:11 am

The engineer from your electric company may not know much about how solar panels work. The "no outlet" comment is nonsensical, when the panels are open circuited, there is no electricity being generated, just a potential across the terminals, with zero current flow. Panels that are in use are expected to last decades - whether or not they are in use doesn't really matter as far as their longevity goes.

Microinverters on each panel is one possibility, do you know the brands of them? Do you know what brand the PV panels are?

With that many panels already on your roof and a bit of energy use economy in the house, you really should be able to minimise your electricity bills. If the original company has abandoned them (get that in writing) it is probably worth getting a competent installer out to have a look and get the system functioning properly.
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Re: are panels safe when just sitting on a roof turned off

Postby confused » Mon Apr 30, 2018 11:48 am

they where installed by Solar city now Tesla but I am not sure what brand the panels are. they are broke down to three different systems with three different inverters.at this point all i can tell is that the inverters do not come on, except for two panels the one with breakers and one under the meter all others with switches are locked with my lock and still on but the breakers are turned off and inverters switched to off i did try restarting but nothing happened. I don't necessarily care mostly want a safe house at this point i need to start tearing out all the drywall and insulation in over 700 square ft of my house including the kitchen.
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Re: are panels safe when just sitting on a roof turned off

Postby Gordon-Loomberah » Mon Apr 30, 2018 11:52 am

For a system that size, the 3 separate inverters will be for 3 phases.
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Re: are panels safe when just sitting on a roof turned off

Postby confused » Mon Apr 30, 2018 12:08 pm

if the system is causing high voltage spikes what would they have done wrong? i get as sometimes up around 150volts on one leg regularly 130volts and 260-270 volts across....thanks for all the information i really appreciate it..
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Re: are panels safe when just sitting on a roof turned off

Postby Gordon-Loomberah » Mon Apr 30, 2018 12:43 pm

Without seeing any data logs all I can suggest is possibilities.

How far are you from your nearest transformer? Often the transformer voltage is tapped a bit higher than standard voltage to make sure the line voltage is above the low limit at the more distant sections of the line, especially when there are significant loads on the line. Undersized street cabling can make the volt drop problem worse. Line voltage can fluctuate significantly due to undersized transformer and cables for the applied loads, even in the absence of any solar generators.

If you remove a significant load and replace it with a generator, solar in your case, the voltage can go high- well above the safe level for appliances connected, resulting in blown light bulbs or motors. 150V is bad news for most things designed to work at 110V. Depending on its settings, an inverter will disconnect from the grid at some voltage well before 150V is reached.

If you see that sort of voltage when your inverters are not producing any output, your power company needs to fix it, to bring the voltage within the standards. If you regularly see 130-150V, it is not surprising your system has been so disfunctional. However, the installers should be onto this sort of thing, it really is the basics.
It would be a shame if you stopped using your system because of a grid problem (along with incompetent installers).
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Re: are panels safe when just sitting on a roof turned off

Postby confused » Mon Apr 30, 2018 12:56 pm

yes my system did start shutting off at one point the system shutdown so often it didn't register any production for a couple days. light bulbs last a few weeks cable boxes and dvd players 6 months to a year appliances ugh...as far as installers they say its not on them even though we have asked them to come out and meet the engineers from local power company they did come once but was after a bad storm and the power company had to cancel now they won't come out. this has been a nightmare for me i am one call to fire dept from having my certificate of occupancy pulled. I would never recommend them to anyone they have no interest in taking responability for anything.......thanks i really appreciate the help
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Re: are panels safe when just sitting on a roof turned off

Postby confused » Mon Apr 30, 2018 12:59 pm

I am about 150 feet from the transformer the power company has upgraded to heaviest line they have it is anew transformer also i think they said a 150?
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Re: are panels safe when just sitting on a roof turned off

Postby confused » Mon Apr 30, 2018 1:04 pm

so its probably on the power company end but the solar company should know what is going on correct?
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Re: are panels safe when just sitting on a roof turned off

Postby Gordon-Loomberah » Mon Apr 30, 2018 1:12 pm

It could well be a 150kW 3phase transformer, that could supply quite a few houses. 150' = 50m is quite close, so if they have put in the largest line, then volt drop/rise shouldn't be a big issue on the grid side. I wonder if the cables from your inverters to the mains are of sufficient size?

Do you see those high voltages when your PV system is not operating?
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Re: are panels safe when just sitting on a roof turned off

Postby confused » Mon Apr 30, 2018 9:44 pm

yes they happen all times of day and night we currently have a computer hooked to our power lines coming into the house that has recorded these spikes and there are times it will drop down to around 100 volts or as low as 0, the power company blames it on the panels they feel the panels are coming on at night not sure how that works with no sun .Or all these incidents occur during other issues such as the prison power outage thats on another power grid again not sure how that works.one theory i have been given is that the power company infrastructure is outdated and had so many repairs/ splices that its just not working properly,the whole thing is odd because although some others on this grid have had issues none as extensive as us and we are the last house on the leg of the grid you would think others would have the issues.
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