Time for a new grid tie?

Scalene · November 2014

Hi,
I have been working on slowly displacing my grid consumption with solar and have just replaced almost all of my 12V panels with 24V panels.My power out from my PV panels is at 1825W
2 of my panels are still 12V in series ,[see signature] how will this effect a new grid tie?
I have been playing around with Sunny design and have found a SMA 2500U or a SMA 2000HFUS
Might it be better to replace the 12V panels?
all of the 24v panels are between 7,78 and 8.05 load current
the 2 12v panels are 11 load current and 13 short circuit current.
thank you for any relevant feedback.

Aguarancher · November 2014

Re: Time for a new grid tie?

Hope you have many smoke detectors and they are all functional..

Scalene · November 2014

Re: Time for a new grid tie?

Why do you say that, it is running fine! the 24v panels are in parallel and the two 12v panels are in series...the 28-50v inverters run w/out glitch. My current VOC for the whole array is ~36V I want to upgrade to a string inverter and put them in series. There will be 222v from 24 volt panels and 44v from the 12v panels. the Amps are all at 8 and the greater amp rating for the 12v panels is not fail, but I loose about 2A. So totally there is 266V, the 2500U has a higher startup than the 2000HFUS and I was wondering if the 12v would have any consequence in series...[if they had the same amp or greater. I found the answer to my other question in a differnt forum/thread, the String inverter will turn off and not back on again if high temps are encountered during the day.[ The startup in the morning and shut down are different voltages] My question is
[2]12v 210w 11a in series is 410w24v11a or 210w24v11a?

Photowhit · November 2014

Re: Time for a new grid tie?

Do you have the power companies approval to do grid tie?

I think the fire thing was all the exposed wiring, and perhaps the panels flush mounted on the roof, generally considered poor installation technique.

Scalene · November 2014

Re: Time for a new grid tie?

I do not do exposed wiring, I excessively ensure no bare wires....and put everything in conduit. Historically my errors seem to be in tightening down connections.....no matter how tight it seems at the time they could always use a little more.
My meter has been spinning backwards since this morning and my Ekm meter indicate forward current still.
I have a chest freezer, a mini frige/freezer, 2 computers 1800 watts flat on roof 185"W, and my Wattvision pairing indicates my usage as positive when my meter is spinning in reverse!

(I do not have a hot water tank, I use a tankless propane one)
I believe the culprit in the fire was my Jatropha Gossipfhilolia, it spits seeds![one got stuck somewhereitshouldntve:grr

Scalene · November 2014

Re: Time for a new grid tie?

{the panels are insulated from the metal roof with wood[best I could do] and the frames are grounded to an independent 10' stainless screw I was using for my wind generator, had to quit, no wind, it is in landfill now I think}

solar_dave · November 2014

Re: Time for a new grid tie?

Well code requires single connection under a clamping screw and protection from case chafing when wiring passes into an electrical enclosure.

Scalene · November 2014

Re: Time for a new grid tie?

I did just notice a small scrape on one the outside added 120 line, the line not incl. in the Romax 10-2w/gnd.
the power leads are for the EKM device are added under the line to the box outside, where the 240v originates.
There is a double breaker in that box, for 240v, if I put another 240 breaker in the box pictured for a SMA string inverter, is there any problem with that?
I will wrap the scrape/bend at the next convenience.

Photowhit · November 2014

Re: Time for a new grid tie?

Attachment not found.

Exposed wires all connected to non code compliant inverters. You understand the electric company can shut off your utilities for this?

Photowhit · November 2014

Re: Time for a new grid tie?

I also don't know or care how these are built, but the fan at the top or the bottom is the only way you shouldn't install my Prosine inverters. I don't know why, heat rises and it would make sense to me that this would aid in cooling, but it is not recommended for the Prosines.

BB. · November 2014

Re: Time for a new grid tie?

Sometimes, fan motors do not like "thrust loads" (weight of fan pulling/pushing on bearings).

-Bill

inetdog · November 2014

Re: Time for a new grid tie?

The rule of thumb you can start with is that to be placed in parallel on one MPPT input panels need to be voltage matched within 5% for best results.
And for series connection they need to be current matched within 5% instead.
You can tolerate greater mismatch in some circumstances, but the panels that you mention would probably have to be used in separate strings feeding separate MPPT inputs to get the best results.
Your decision from there on where you want to go. Get an inverter with two or more MPPT inputs or give up using the old panels or use them for a separate system.

Scalene · November 2014

Re: Time for a new grid tie?

With the greater proportion [6/8] of my panels being 235W8A24V and just 2 being 12V210W11A,[Evergreen 210 12v] I have notices some small changes in my inverters behavior. Other than the digital lcd.[which I do not think is very good]
I do not have any 'thrust loads' only small fans and a washing machine that seems to make a different noises everytime it is run...
with one inverter turned on the fans do not come on, with both inverters on the fans come on. The reccomendation was 1/2 of the rated load for full time use and in Nov and flat panel mount I think that is O.K. 1824/2=912 912/1200~ 1/2 rated load and panels not at full power angles...
the wires connecting the grid on the bottom are not exposed, they are in a plug, there is no way around the DC exposure for me right now on top, I guess I could tape it all up, it is only exposed milimeters of wire and the connections themselves.

Photowhit · November 2014

Re: Time for a new grid tie?

My point is they are NOT code compliant and can't be made to be code compliant, and in most people here's opinion shouldn't be used, at least by the other threads on these plug and play grid tied inverters. I'm a bit surprised, one of the Mods hasn't said anything about them, I think Bill's reply was to my comment of the installation and fan orientation.

Scalene · November 2014

Re: Time for a new grid tie?

all I can say is that once I shed the batteries and the wind generator I stopped blowing the DC fuses.
I am finally in the output market for a 'proper' grid tie inverter after a long time of slowly buying and building and learning.
I no loner intend to use a battery back up system, I will use a generator, gas or propane, and maybee a off grid inverter for emergencies.
I have had no mishaps on the AC side of the project. It is not my opinion... it is history.
I have had to make numerous trips the fuse store, though, for a while now.
I have 222v with 24 volt panels within 5% my 12v panels are 37%out at 11a but a greater amp for 266 volts. almost in the market for a code compliant grid tie. They are expensive and finicky. I still plan on getting a string grid inverter[UL Listed 1741 I think]

Aguarancher · November 2014

Re: Time for a new grid tie?

The question you have been avoiding is, does your electrical provider know you are back feeding electricity into their grid..I take it the answer is NO.
Your set-up is Dangerous and the likeliness of you having an accident is High.
That is why my original question and concern whether you had operating smoke alarms.

Cariboocoot · November 2014

Re: Time for a new grid tie?

Thomas/Scalene has a history of dangerous and illegal power system experiments. We gave up long ago trying to advise him on doing it safely and legally. His adventures serve only as an example f what people should not do. His understanding of power systems is minimal which increases the risk. So far it has been luck that has kept the failings from being worse than they have been.

The power company is likely unaware of what he's been doing for the same reason he has suffered no failures on the AC side: the inverters used are simply too small to make a difference on the household other than apparent load reduction from the grid.

I will make this clear once and once only: absolutely no one should be doing this sort of thing. This is not opinion it is fact.

Scalene · November 2014

Re: Time for a new grid tie?

Thank you for all your support and guidance, and to those who tried to give constructive advise/dissent
YES the power company is AWARE of my solar panels and soon hopefully an outside SB 3000US...maybee by spring summer.
I do not fool with the grid in experiments, actually I am kind-of fearful of it. The most I ever did with/to the grid has been to set up 240V at my box instead of 110 only.
And who cares if someone actually IS messing with the grid anyway? Means power failures for us SURVIVALIST DOOMSDAYERS!
[to test our preparations on]
thanks again

Cariboocoot · November 2014

Re: Time for a new grid tie?

The grid will survive your experiments.
Your house may not.

Photowhit · November 2014

Re: Time for a new grid tie?

Scalene wrote: »

I have had no mishaps on the AC side of the project. It is not my opinion... it is history.

Just for the record, I had a good friend, who I've lost touch with now. I rode with him one night through Tallahassee, Florida. He ran 3 lights! he told me he did it all the time, and had never had problems... I suspect you know the rest of the story....

...I bet he has never ran another light.

I'm a bit of a prepper/realist/fatalist. I believe we are over populated and I'm too much of a pacifist to believe I will own(possess) my array/off grid system too far into a collapse (though my best friends are big hunters) I suspect if your looking at prepping you should be working on an off grid system rather than a grid tied system. Now excuse me I have to rig up a dehydrator to run off the warm air off my wood stove. The thermostat went out on my Excaliber and I have a bushel of apples, and 30lbs of sweet potatoes to dehydrate.

Scalene · November 2014

Re: Time for a new grid tie?

My house will survive I think....thanks for the concern though. Its got new floors,carpet doors plumbing etc...
While posting this afternoon I re-vinyled my shower, A few years ago I installed propane, I just took out my hot water heater and put a new line on my propane for a tankless one and all of my panels are 24 volt now I have 400watts of 12v panels sitting under my house and a 12v grid tie doing nothing.
I think people shoulda make preparations for the permanence of the grid, its sustainability, perseverance thru all kinds of increments, and care enough to update/upgrade it to pure sine wave electricty from solar-wind-hydro-Natgas. The electricity may not be as lethal...potent or healthy but ...
I disagree with mainstream soothsayers though, if survival is the real goal the permanence of the grid is reality, it is not going away and will be there in whatever form...unless it has not yet reached all areas yet, which it WILL DO! maybe by that time the WHOLE WORLD GRID will be fed by everything accept coal and oil. Then the grid will have a new issue. Until then I am content with ithe grid being there as a permanent backup to make sure my foods fresh, I have lights, and hot water. I think that even when "the grid" will be all sustainable without oil/coal, that dependency on said "the grid" can be minimized to small percents. Resupply the power companies one rig at a time.
The EKM meter is still saying my current flow is forward, the CT's are installed properly so, I will contact EKM again. The revkWhrs are counting though, not out to Wattvision.

Cariboocoot · November 2014

Re: Time for a new grid tie?

I guess that technical communications module was a waste of time after all. :roll:

Scalene · November 2014

Re: Time for a new grid tie?

So it seems, I have had NO LUCK measuring ANY of my solar endeavors, these metering devices , although sketchy, are nonetheless the best I have gotten so far. I wonder if I get Sunny Web connect or Sunny View later on if even they will work accurately and precisely simultaneously. Ekm just came out with software fore their 'Omnimeter v4 [version4] still seems buggy, I have the old Onimeter v3 and a version2 but I think sticking with the agenda of moving forward, and just accepting the reduction in my bill without knowing exactly how....and waiting hopefully for some plug and play measuring one day. I really woulda liked to see my revkWhrs on Wattview though, even in data form woulda been nice. We'll see what EKM meter has to say about this next problem, we just resolved a problem with a auxiliary gas meter input that was glitched, now counting my propane consumption goodly.

Photowhit · November 2014

Re: Time for a new grid tie?

Could you go old school and buy/pick up an old analog meter? I was told the Power company here would give me one if I wanted sans cabinet/base. They are swapping them out for new digital meters.

Scalene · November 2014

Re: Time for a new grid tie?

I can get a meter inexpensively on e-bay that would measure my inverter output I guess.....the one on the panel is analog. Maybee a second at the grid tie connection?
What would occur after a collapse[ with power] with everything today so dependant, realistically, even with oil and coal, I do not really foresee the realistic expectaion, even worse case of the power grid going down for any legnth of time; having to fight for access....[after a collapse...] is a different scenario I think, Mad Max, beyond the electodome....like going to town to charge your batteries, or use the town solar array...or a neighbors generator...
I do not think trying real hard to measure my solar output is going to be anything but a waste of time untill I can standardize it a little bit more, Like with a SB3000HFUS! the 2500U is too high a startup voltage.

I do not think it is good today to have to watch your refrigerator time, or plan showers, or laundry. In the greater sceme of things I believe these issues shouldbe granted and transgress to 'background programs' not 'applications'. To use Windows OS an a figureative sybolic reference.

Time for a new grid tie?

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