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Unless the wiring fails shorted. And this does happen, though not nearly as often as opens. There is no absolutely fail safe method, only varying degrees of assurance. This is often measured in "nines", as in "how many nines do you want?". Asking for 3 nines would be 99.9% reliable, 1 in 1000...

Your formula is greatly over estimating the panel power output. It assumes power is Voc * Isc. For example, Canadian Solar CS6R-395MS-HL panel as these specs under STC: Voc = 36.6 volts Isc = 13.77 amps Power = 504 watts (this is wrong) When operating at max power point: Vmp = 30.6 volts...

Does the time jump to some fix time in the past? This would be a symptom of a reset occurring. Or is it a fixed number of hours offset from real time? This would be a symptom of time zone corruption. Or is it random? This would be a symptom of various other faults. Is the unit on the...

MPPT efficiencies are very high because the voltage difference is low if your strings are properly configured. This is why it is best to build strings with Vmp of about 350 volts, the PV to DC HV bus conversion is then very low loss. EG4 18KPV lists MPPT efficiency as 99.9%, effectively no...

Perfect, thanks. Mike C.

That risks the entire house overloading the inverter, then you get no power. Since you don't know when the grid will fail, you can't manage your loads to be within inverter ratings at all times. Mike C.

Price listed is $1333. Capacity is 3.552 KWH. Doing the math... $375/KWH. That's double the cost of Ruixu. The system requires a minimum of two units which is where the 7 KWH number comes from, but that's not the module capacity. Mike C.

They say "UL Certificate" but then only show a CE one, and suspiciously, they have blurred out much of the information including the manufacturer. Warranty of 18 months, if it has any value at all. Also, min order of 2 units. Maybe you need 2 to have a chance 1 works? Not inspiring. Mike C.

Too much work to get what should be very basic information, like what something costs. Mike C.

Seriously? Full retail rate for any excess? Wow. It looks like the system will produce about 26.5 MWH per year, and at, say, $0.12 per KWH, that's $3180 of power. I'm still skeptical your deal is this good. Mike C.

Has the 20W idle been verified? Mike C.

The Emporia Vue 2 is more lame than I thought. The problems I'm having or had: 1. One channel in intermittent. The little phone jacks are not very reliable. 2. The "1 second" data is not even 1 second resolution for the last 3 hours. They average it to 1 minute and it appears only when you...

When I use the PVWatts Calculator: https://pvwatts.nrel.gov/index.php I get about 121 MWH per year from a 100 KW panel array. That works out to an average of 332 KWH per day, so not quite as productive as you expect. One issue is that my roof is ridged north/south so the panels are flat...

No, you don't. You just claim the system cost on your taxes and you get the 30% credit. if you get audited, then you produce the invoices showing you bought the equipment and it clearly meets the rules. You do not have to show a permit, plan, or inspection for the credit. Plenty of off grid...

If your service is 200 amps, then all 200 amps is available to the main panel with the switch in the "Utility" position. But power is also available to the inverters through the grid connections directly to the outside disconnect where they could be charging the batteries from grid. I believe...

The high desert can have cold temps, your record low is -29 C (-21 F). You will need to pay attention to the Voc rise in cold so you don't blow out your inverter MPPTs. Also, if the battery is not in conditioned space, then your battery needs a heater and that will drain energy during the...

Given ground mount (removes RSD requirement) and no shading (removes optimizer utility), feels like the diagram you proposed generally works. Manual DC disconnect seems code compliant. Note that the RGM doesn't measure the total SOLAR production, it measures the total INVERTER production. Not...

As long as the moment the grid failed, you were under the inverter load limits for the entire house. If you are over the inverter limit, it will trip out and then you have NO power to anything. You will have to manually load shed, then restart the inverter. In contrast, with a backup panel...

It really annoys me that critical limiting values like this are not in the documentation for the unit. All you got is some verbal or email to rely on, and that's from a reseller in China and not even the manufacturer. Also, how are you going to get 100 amps to pass through with the load...

97.5% per the spec sheet. A string inverter will be as good as a microinverter. They both do the same job, PV to AC, so why wouldn't they be similar in efficiency? Are you accounting for the clipping since microinverters are often less power than the panels they are attached to. For PV to...

I have grid so the power drops don't fit this profile. The time of the drops have been about 6:20 pm for the first two 8 days apart, then one in the early AM about 5 days later (no exact time since no alert is posted). If it was once per day, you'd think it would happen at the same time per...

The pricing is not that far off other similar spec'ed units so the feature set is not that implausible. The inverter is two 5 KW 120 VAC inverters internally. There is no autotransformer. A video of various load tests: Not exactly done with scientific vigor, but the unit does seem to...

In a grid attached, net metering, no battery system, microinverters on the roof can then basically feed directly into the breaker panel and you have to do minimal rewiring of the house to get it up and running. This is why they exist, for quick retrofit of a house without having to install an...

I only touched on many issues. There's a lot to this solar thing. I think you mean "inverter". In reality, what the inverter does is "transform" PV DC into AC, so "transformer" is actually a decent name, but it is taken for AC to AC magnetic transformers. An inverter gets the name from...

As to Greenlancer, they appeared to have a plans service for $350 (no battery): Seems reasonable. But it does not include PE stamp electrical and structural plans. When my job was was quoted with them, that was $450 extra for each, or $900 more, to have PE stamped plans and this involved...

The stainless metal plate behind the inverter was a backsplash sold on Amazon: https://www.amazon.com/gp/product/B091FYT7KH I don't know if I technically need that or not but thought it made the install look nice. I was NOT going to mess with Hardie board. Yuck. I may need something similar...

Close, it is the mean square voltage of a sine wave. Power is V^2/R, so the power tracks with the square of the voltage. That's is why it is called RMS, root mean square. First, you square the sine wave, then you take the average (mean), and then you take the square root of that. It is the...

In 2013, I paid $52,800 for the well drilling. That works out to $5.50/ft for 32 wells, 300 ft each. I supplied the pipe and had another contractor do the header system, this was just drill the wells, insert the pipe, and grout the wells. I think I was at $69K for everything for the well...

Excellent. The connectors are: https://www.aliexpress.com/i/3256805461901492.html Choose the 4 pin bayonet style. They are sold as a male/female set. The two uses will be to either make a Solar Assistant cable that doesn't have to go internal to the machine, or to build an extension cable...

I see two steps, step 1 is the cable, step 2 is the config. I don't see two methods of connection. Wats247 created this hack of a cable to bypass the external Wifi port, but that is still the same signals electrically. I will report if the connectors I have ordered fit properly. If they do...

Thanks for the pictures, they confirm my 8 x 8 trough won't cover the battery terminals unless I make it proud of the wall some amount. The 9.6 inch depth dimension given in some of the documents apparently forgets to include the back brackets. It would also be nice if the ground screw wasn't...

80s is 256 V nominal, not unreasonable electrically. When you get to this size, you do end up being constrained on cell sizes. For example, using a 100 AH cell is now a 25.6 KWH pack and will be heavy, like 500 lbs. If you target around 5 KWH, rack size, you need to find 20 AH cells which...

Pretty good examination of the hybrid architecture. Main takeaway for me was that it is best to get the array string high enough to avoid needing the PV boost stage. I think this is about 360 volts. if you can do that, then your PV to AC efficiency rises. Mike C.

This would do the trick: https://www.currentconnected.com/product/tyco-kilovac-dc-contactor-500a/ Has a coil "economizer" which reduces steady state on power to about 1.5 watts. Your RSD button would have an NC contact that keeps the coil powered by the battery output voltage. Hit the RSD...

Best to put it close to the inverter. The inverter switching noise will induce noise on the cables and the cables act as antennas. Put the ferrite on the cable to provide high frequency isolation between the invert and the cables. This effectively denies the noise an antenna from which to...

I just couldn't see the cost benefit ratio to buy REC versus Canadian Solar. I bought a pallet of 30 CS6R-395MS-HL for $3495 delivered. $116.50 per panel. The REC might be better, have better warranty, etc, but for more than double the price, it didn't seem worth it. I bought it at Signature...

Manual: https://cdn.prod.website-files.com/5fad551d7419c7a0e9e4aba4/65f09afa2bcdbd0561194ad0_RSS%20Transmitter%20Installation%20Manual%20002-00118-00%204.2%2020240301.pdf Some quotes: "One transmitter can support up to ten strings with one core and up to twenty strings with two cores." "Pass...

Kornbread, I've joined the N3H-X10-US club. On its way. This will be an 11.7 KW array with one or two EG4 wall batteries. Not sure if the batteries will talk to the inverter or not, willing to go without battery comms. I am VERY interested in making Solar Assistant work so it can monitor...

Expect to clean it periodically. Mike C.

There is no way they can provide enough thermal mass to effectively regulate the battery temperature even with a phase change. Just not enough energy storage. Are they going to have a phase change for being hot or for being cold? You can't make a material do both since a gas state isn't...

AC output power total: 1843 watts Battery input power: 1851 watts Indicated efficiency: 99.6 % This fails sanity check. It realistically should be about 90-95%. It sure feels like a math error by a factor of 2. If you double the current readings, then: AC output power total: 1800 watts...

A way to (mostly) reverse this is a relay where the NC contacts shut down the inverter. The relay has to stay energized or it drops and closes the shut down signal on the inverter. You can put the relay right next to the inverter (maybe inside it) to minimize the exposure of the closed contact...

Anybody using the Sungold SG10KHB-48 hybrid inverter? https://sungoldpower.com/collections/hybrid-solar-inverter/products/10kw-hybrid-inverter-48v-split-phase 15 KW PV, 4 MPPT, 10 KW AC, 48 volt battery input. Looks decent on specs and at $2400, might be worth considering since that is less...

EG4 requires a user to have an NDA before they can make suggestions? And then requires they keep those suggestions secret? Weird. Mike C.

Code says: "Where PV system dc circuits run inside a building, they shall be contained in metal raceways, Type MC metal-clad cable that complies with 250.118(10), or metal enclosures from the point of penetration of the surface of the building to the first readily accessible disconnecting...

It is so hard to get straight answers on exactly what I need to pass code and inspection. I'm starting to think the right path here is to install the inverter and panels, no battery, get that inspected and utility approved for net metering. Then, someday later, batteries might magically appear...

The point was a 2200 W V2L port is a practical solution if you have an inverter with battery to load level the power. Mike C

This is a complex subject with no simple answers. the cycle counters in various devices often simplify this to such an extent they are useless. The cell damage is highest at near 0% SoC and near 100% SoC. So keeping the battery off those limits improves life. A cycle is NOT any reversal of...

The Enphase battery solution is kind of lame. Since they promote microinverters, the panels are AC coupled. To charge the batteries, you then have to convert AC back to DC,, then to use the battery to make AC power, you have to go DC to AC again. 3 major conversions between the solar panel...