diy solar

diy solar

10K PV and Solark Install

Ok... Just figured out how to do the "Quote" thing to answer specific questions.
What fraction of your available PV production is curtailed to avoid export to grid?
The Sol-Ark has some pretty advanced programming features ... and a big Dose of "PFM" (Pure F**** Magic)
They have a wide range of programmable features. My only other experience is a LV5048 (also a very nice system)

Under the "Limited to Home Mode" you can identify how much you draw from the Grid. (Factory set is 50 w/h) I have adjusted mine to 150 w/h. This seems to work best for me based on my intermittent High load usage. The other 11.85 KW is available for use.

I am also running a variable speed pool pump. Over the last few months I have been learning the timing of to program my pump for best use. I have a 35,000 gallon pool ( & yes.. then is a lot of water)... I have been able to adjust the program to maximize the filtering.

Hope this helps
 
But I am fairly sure @Hedges and others around here would recommend something other than the Solark for handling loads like A/C. From what I gather, inverters with transformers are better at handling surges.
And since I also have a transformerless inverter i would recommend replacing the devices that have surge with more efficient variable speed inverter driven devices. In the long run energy conservation has greater payback. It all depends on where you are standing.
 
I have been thinking about the possibility of adding another inverter too. But I am fairly sure @Hedges and others around here would recommend something other than the Solark for handling loads like A/C. From what I gather, inverters with transformers are better at handling surges. I will be constantly thinking of ways to improve my system. DIY is forever.

My rule of thumb, and limited measurements, is that starting a motor takes 5x nameplate current for 0.15 seconds. Some motors will specify LRA (locked rotor amps) which can be used instead.

If SolArk continuous rating, or multiple-second surge rating, exceeds that then it should be able to start such loads. If not, then you need a more powerful inverter, or a soft-start, or a motor with variable-speed drive to gently ramp up. I think SolArk's continuous AC capability is 5x 1.5kW or maybe 2.0kW, don't remember the surge rating. If you want to add an inverter, can two be paralleled?

As for variable-speed drives, I've seen a problem with them. Running my transformer-type Sunny Island and transformerless Sunny Boy 10000TLUS, I tried adjusting speed of 3-phase 2 HP pool pump (Hitachi VFD) as a variable load and saw something light "IGBT error" on the Sunny Boy. My theory is that the bad PF of the VFD upset it. With six diodes (four used with 120/240V split-phase) rectifying AC onto a capacitor for 400VDC bus, there is zero current draw until sine wave reaches DC bus voltage, after which capacitor draws all the current it can trying to clip top off sine wave. I was able to cycle the Sunny Boy to reset the error and avoided running the pool pump while off grid after that.

So before implementing VFD, borrow something with comparable VFD load and try it out first. Maybe a 3-phase power tool like air compressor or bench grinder. I suggest doing this while SolArk is within warranty, just in case.

You already have AGM and will switch to LiFePO4. If you did buy one or two Sunny Island (if one, need 120/240V transformer), the AGM on it would take care of surges. They provide 3 second 11kW surge each. Or another brand. But too much expense and effort, better to fit loads within capability of SolArk (e.g. install mini-split to operate if grid is down.)
 
As for variable-speed drives, I've seen a problem with them.
Good input. My only experience is running two inverter driven refrigerators off my Skybox. I also ran another one of them off a small 800 Watt inverter on a 12 volt pack as a backbup for my sister.
 
I am also running a variable speed pool pump. Over the last few months I have been learning the timing of to program my pump for best use. I have a 35,000 gallon pool ( & yes.. then is a lot of water)... I have been able to adjust the program to maximize the filtering.

I put in a variable speed pump, before it was a thing offered at residential pool shops. I tried a 2-speed, but as DE filter starts to get loaded, 3600 RPM seemed like too much strain and 1800 RPM didn't move enough water.

I picked up a 3-phase 2 HP motor, and a Hitachi VFD. It has a dial on the front and analog input on the back. I imagined making a servo-control (PID) to adjust speed to maintain battery at float while operating off-grid. Because Sunny Island communicates need for AC power by frequency shift, this would seek to keep frequency between 60.5 Hz and 61 Hz. Above 61 Hz, Sunny Boy curtails PV production.

The 3-phase pool pumps I see available have electronics packaged waterproof with the pump motor, and include features like detecting if someone is stuck on the pool inlet and shutting off. (Top-hat inlet covers instead of simple grates, and dual inlets, are another way such safety hazards are addressed.)

Since poor PF of the VFD seemed to be a problem for my transformerless Sunny Boys, I bought transformer type to replace them. I might use the transformerless ones strictly grid-connected.

Don't know if you have any analog or digital interface to your pump control. Or if you can program a curve to approximately match surplus production. The things we do to game the games utilities come up with to discourage "green" power by homeowners. They play straight into the hands of Tesla Powerwall and the like. If you can program your inverter to bank surplus in a battery and toggle loads on when battery full, that could do it.
 
Ok... Just figured out how to do the "Quote" thing to answer specific questions.

The Sol-Ark has some pretty advanced programming features ... and a big Dose of "PFM" (Pure F**** Magic)
They have a wide range of programmable features. My only other experience is a LV5048 (also a very nice system)

Under the "Limited to Home Mode" you can identify how much you draw from the Grid. (Factory set is 50 w/h) I have adjusted mine to 150 w/h. This seems to work best for me based on my intermittent High load usage. The other 11.85 KW is available for use.

I am also running a variable speed pool pump. Over the last few months I have been learning the timing of to program my pump for best use. I have a 35,000 gallon pool ( & yes.. then is a lot of water)... I have been able to adjust the program to maximize the filtering.

Hope this helps
Ok, where is the forum to learn about pools?! Just bought a house with one, and I have no clue.
 
Yeah.. that was sort of a kidding comment. Thanks. Always learning something new is fun.
 
Most of us just jump off the deep end. And hope it has water in it.

After awhile it turns into a green swamp and you have to do something about it.

I learned to ignore instructions from the pool shop that said to correct water chemistry first, then chlorinate. It worked better to chlorinate and clean up the water, then check chemistry. Otherwise you buy chemicals you don't need.

Automatic pools sweeps may be nice. But the one I put on suction side wrecked a couple pump motors. Had to adjust suction bypass to the point of cavitation to get enough flow to operate the sweep, and bearings in motor failed.

Pool covers keep debris out and chlorine in, and reduce evaporation. But unless they are made with good UV inhibitors, after 3 years you have a bunch of blue plastic flakes in the pool.

Pipes develop leaks. I would'a thunk it was on the pressure side, but bypassing that didn't stop the water loss (about 1"/hour) I saw while filtering. Turned out to be suction side. Bypassing that I've been filtering for a couple weeks, have it cleaned up. When I fill the Jacuzzi to overflowing (1' higher than pool) I again lose water so I'm going to try putting rubber pipe plugs in the outlets.
 
Most of us just jump off the deep end. And hope it has water in it.

After awhile it turns into a green swamp and you have to do something about it.

I learned to ignore instructions from the pool shop that said to correct water chemistry first, then chlorinate. It worked better to chlorinate and clean up the water, then check chemistry. Otherwise you buy chemicals you don't need.

Automatic pools sweeps may be nice. But the one I put on suction side wrecked a couple pump motors. Had to adjust suction bypass to the point of cavitation to get enough flow to operate the sweep, and bearings in motor failed.

Pool covers keep debris out and chlorine in, and reduce evaporation. But unless they are made with good UV inhibitors, after 3 years you have a bunch of blue plastic flakes in the pool.

Pipes develop leaks. I would'a thunk it was on the pressure side, but bypassing that didn't stop the water loss (about 1"/hour) I saw while filtering. Turned out to be suction side. Bypassing that I've been filtering for a couple weeks, have it cleaned up. When I fill the Jacuzzi to overflowing (1' higher than pool) I again lose water so I'm going to try putting rubber pipe plugs in the outlets.
Wow. Looks like I have a lot to learn! Thanks for the tips.
 
You already have AGM and will switch to LiFePO4. If you did buy one or two Sunny Island (if one, need 120/240V transformer), the AGM on it would take care of surges. They provide 3 second 11kW surge each. Or another brand. But too much expense and effort, better to fit loads within capability of SolArk (e.g. install mini-split to operate if grid is down.)
Sorry, I'm not getting on here as much because I am away from home. When I thought of everything I've heard about inverters with transformers, I just assumed adding a 2nd inverter with a transformer might be a possible solution. But I knew that communication between inverters would be an issue. It seems simple to just put the air conditioner on a separate off grid inverter. But I know energy would be wasted if I did that.

Adding another Solark might solve the surge issue but then I would be over the AC limit allowable for grid connection without special insurance for the possibility that I might send over 10K to the grid. I will get a quote to find out exactly how much the special insurance costs.

My current A/C unit is fairly new and I think it is efficient because our bills are low compared to what I see others mentioning. I don't have a way to check how much my A/C unit uses but here's the tag -
1618743048377.png

I don't know how to measure my A/C draw but I think the spikes on this screenshot might be from the A/C being kept track of by the CTs.
1618742877907.png
 
Here's a screen shot for the whole day yesterday. I have no idea what that huge spike is at the right of the picture.
edit: the larger spikes might be from my wife using the oven. The stove has a 50A breaker. The A/C only has a 30A breaker.

1618744399956.png
 
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Excellent... this is the comparative info I have been looking for. Here is the graph from my system yesterday.Screen Shot 2021-04-18 at 5.38.19 AM.png
 
Compressor running current of 16A x 230V = 3680W
My 5x starting surge assumption comes to 18,000W which is about the surge rating of SolArk, might start it.

Locked rotor amps is 109A x 230V = 25,000W, might need two SolArk

Perhaps you can add as second SolArk with batteries connected configured for no backfeed. It's inverter output plus your main one should be enough.

Sunny Island is rated for 11,000W 3 second surge. Would take two to start that motor.
My smaller AC is rated 12.1A running and 57 LRA so I expect even a single Sunny Island plus transformer to start it.

Maybe a soft-start would drop the starting current enough for one SolArk. Apparently some have quite a dramatic effect.

You could leave the main A/C on the grid side and install a suitably sized mini-split for use when off-grid. Some cost a fraction what the SolArk does.
If a mini-split is inverter drive, I do wonder how well the transformerless battery inverters perform with them. Ought to get someone else with a SolArk to test out its operation. Or buy from Amazon so you can return no questions asked?
 
We have a window A/C for the bedroom so we'll be fine.
I'll be doing a bunch of tests when I get time. I am not expecting much because I have seen reviews and I never expected to run my central A/C when the grid is down.
My wife said the surge at about 18:00 was the oven and the one about 23:00 was a toaster oven.
Maybe the A/C kicked on at the same time as the toaster oven.

I need more data. I'll figure it all out someday.
 
That is decent production, 5.73 "Sun Hours" on your panels. How does that compare with the Solar Watts estimate for your area?

I am in So Cal, so probably a little longer day. 4 days ago, my 4.8 KW of panels made 30.3 KWH. 6.31 Sun Hours. It was totally clear sky, yet cool. That is my best yet this year. The day after was much hotter, so it fell to 29.4 and them 29.6 KWH, all very good, but then today... 6.2 KWH due to heavy overcast.
 
That is decent production, 5.73 "Sun Hours" on your panels. How does that compare with the Solar Watts estimate for your area?

I am in So Cal, so probably a little longer day. 4 days ago, my 4.8 KW of panels made 30.3 KWH. 6.31 Sun Hours. It was totally clear sky, yet cool. That is my best yet this year. The day after was much hotter, so it fell to 29.4 and them 29.6 KWH, all very good, but then today... 6.2 KWH due to heavy overcast.
When I got quotes to install solar they all said 9 or 10kW would cover our usage.
That's with no optimisers.
Our highest daily usage is about 41kw. That is when it is hot.
 
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