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Sid Genetry Solar

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Everything posted by Sid Genetry Solar

  1. Venerable 555...looks like it's being used as an R-S latch with the digital input thresholds providing the trigger setpoints. Clever circuit. ...I just can't help but wonder how small I could get a PCB with that circuit on it 🀣. Probably could fit it onto a 1.5x1.5" board (using a smaller relay as well)...
  2. No, the limit to the number of turns has to do with the physical limitation of the core hole diameter and the size of the wires. Stacking 4 cores together would (I think) increase the inductance of the choke, allowing for higher voltage operation. Once the 24KHz carrier has been reasonably filtered out, no further reduction of no-load current seems possible. (At least in my experience.) Speaking of a heating element: with a GS inverter cleanly and equally driving all four quadrants of the H-bridge, the chokes get HOT at no load. This in part is why my (unscientific) hypothesis is that the chokes are filtering out the 24KHz carrier--because if the FETs are being firmly driven, there'll be sharper corners on the 24KHz carrier as compared to a PJ. (Transformer also runs nearly silent at no load with the GS design. Tests on the GS 12kw inverter with 11 FETs...the transformer is SO quiet, I can't hear a hum even putting my ear on the transformer. Of course, under load, it does start to hum/buzz.)
  3. Always fun to see someone trying to improve a PJ 🀣. What voltage specifications did you wind your transformer to? Just curious πŸ˜‰ So my current conclusion is that the ferrite chokes are for absorbing/"filtering" the 24KHz SPWM carrier before it reaches the main transformer. The main transformer will appear more or less of a short circuit to a 24KHz signal--which would explain why without the chokes, the idle current is so extremely high. My guess is that yes, while the no load current is a very easy "measurement point", I would expect that a high-idle inverter will also run at a measurably lower efficiency (and higher temperature) due to the non-useable 24KHz carrier getting dissipated as heat in the main transformer. If said carrier can be filtered out via the chokes, then there should be a higher efficiency end result for the main transformer. My personal experience (having tried multiple PJ chokes, a large E-core, lots of inverter design testing, etc., etc.) is that 2 full turns around a PJ ferrite is the maximum it can do. More turns don't seem to help no load. Had someone try gluing 4 ferrites together and running 2 turns through the whole stack--same no-load as a single PJ ferrite with 2 turns. Ditto for the E-core--same as 2 turns around a PJ ferrite. Where it gets interesting is if when running extreme high voltages on an inverter design (referring to 36v on a 24v inverter). While the no-load current remains relatively constant from 24-30v, somewhere beyond that, the no-load current starts to rise again. Adding a second choke (2 turns) on the other leg of the transformer reduces the no-load current back to the former number. Obviously, with the increased voltage and same no load current, the efficiency is going down...but extra ferrite chokes do help at higher voltages on a lower voltage transformer. ...and don't try running a 24v PJ inverter at 36v (or a 48v at 65v). It's going to blow up πŸ˜‰. Been there, done that.
  4. If you're asking about the battery charge settings on a GS inverter--of course, they can be fully configured to whatever charge voltage you need (for the appropriate battery voltage range, of course). What's up with the subject of "24v dc to dc"?
  5. I think the biggest part of the problem is the haphazard firmware doesn't check to see if the AC output has fallen to zero before restarting the FETs. If the relay sticks / doesn't turn off (or wasn't turned off!), it'll try to drive the FETs in inverter mode against the AC mains. (This is a battle that most FETs lose.) If the mains voltage is significantly higher than the inverter regulation voltage, it'll run just a low "inverter throttle", and wreck quite the mess with the AC input and battery (because it won't be synced). Yes, this'll sound horrid, and isn't good for it... PJ really doesn't make much of a change for "split phase"--they use a center-tapped transformer, and (usually) regulate the inverter from just one of the phases (120v). That's pretty much it.
  6. Of course I won't mention that the charge current is both fully user-adjustable AND automatically temperature-gradiated in GS inverters πŸ˜‰
  7. Umm...yeah, those would be the ones. I guess I thought the little switches were back before v9, but...I guess not. Removing one of the resistors would cause it to hit the current limit sooner (AND cause it to overload in inverter mode a tad earlier).
  8. Technically, the constant current limit is set by a hardcode number in the CPU firmware. However, this number is scaled by the tiny SMT "DIP" switches on the "charger" board. This basically is a resistor assortment that shunts the transformer current readout. If you turn one or more of these switches off, it will cause the fixed current limit number to be reached sooner. BUT...there's a monkey wrench in the game: by turning one or more of those switches off, it will also reduce the "inverter overload" threshold (on the L1 circuit). If you feel very electrically handy, it could be possible to wire up a circuit to adjust this "shunting" based on whether the AC Mains relay is on or off.
  9. Sigineer constantly rebooting?? Was this due to overload? (I know the GS doesn't redline EXACTLY at 6kw) Rumor has it that Aims / Sigineer (and related rebrands) "aren't as reliable as you might think." From the photos I've seen of the internals of a 15kw Yiyen inverter, I'm not surprised to hear that their 12kw blew up. Heck, it's a PJ inverter with better software and a better transformer. Same lousy imbalanced FET drive...which simply isn't up to the task. It's a lot of work, for sure. But that's our goal. Obviously, as with any new design, there have been a couple "teething" issues, and several customers have had issues with the control board power supply--but all in all, it's been a very valuable learning experience to make the latest control boards even better.
  10. Let me just sum it up this way: it's a wonder the PJ firmware works at all. I definitely cannot recommend the PJ charge function--but for some people it works very well.
  11. Expect no higher than 6-7kw continuous duty out of the 15kw PJ. They'll do surges and higher loads for a short time, but consider yourself fortunate to reach 50% of the nameplate at continuous load. My "9kw" PJ would redline and overheat at 3kw. Still don't know, per Sean's videos. Have some final testing/tweaks to run (seems a little shy of reaching 12kw continuous at the moment...might need to change the transformer core), then a lot of design and logistics to work out.
  12. Surge current isn't the consideration at hand. See, if you had a 12-24kwh battery bank @ 12v, you'd have considerable amperage available. The issue becomes getting the amperage through the entire inverter and actually being able to accomplish the intended goal without losing the entire power usage in system losses. Remember, amperage is the enemy of efficiency. That's why long-distance power transfer is inevitably at as high of a voltage as feasibly and safely possible. The lower the amperage, the lower the losses. Simple Ohm's Law. 95% load anyway. 6000W / 240v = 25A. Remember that the LRA rating is <1sec, so it won't have any bearing on system capacity (i.e. heat limits), but rather entirely an absolute power limit. No matter what kind of "soft start" you come up with, you will not be able to reduce the startup surge to the FLA rating...that's just how synchronous AC motors work. Well, 240v * 50A = 12,000W, so not exactly. ATS function isn't dependent on battery voltage though; if it works at 48v, it'll work when configured at 12, 24, or 36v as well. GS inverters as of yet do not have a solar charge controller built in. However, they can charge from AC input--though the AC input will have to be able to power the entire load in addition to the battery charge power requirements, in order to charge the batteries. Yes. It'll help considerably to have a Rev. C control board in the GS inverter (which I FINALLY just ordered last night). Once we receive them, all GS inverters will ship with a Rev. C control board. Bonus points if your grid-tie inverters support frequency shift throttling (most cheaper/readily available grid-ties don't)...if so, the GS inverter will be able to gently regulate the grid-tie output as needed for battery charging + loads, etc. If the grid-ties do not support frequency shift throttling (i.e. on/off), the system will be far cruder...but should still work quite well. (If there's a power excess, the inverter will start shifting the output frequency from 60Hz up past 62Hz--or at least until the grid-ties trip off. Expect a slow oscillation here, as most grid-ties will then run a 5-10 minute timeout before they try to power back up again. If the power needs / battery charge is still less than the grid tie inverters' total output power, the GS inverter will trip the grid-ties off again.) Curious then if you have grid-tie inverters already picked out...if so, what are they? No. GS inverters provide true split-phase output, no hacked-up solutions needed.
  13. Yes, we could rewire the transformers / reconfigure the inverters via video call (48v / 120v single-phase output). But we'd have to get some fans to you for 48v. Sean most definitely would have tested the inverters before sending them out. All GS inverters have our very own universal transformer--in other words, out of the box from the manufacturer, they will not function at all. Sean has to wire them to the desired customer specifications, test them to verify functionality, then ship them. Umm...they're still on the website just the same? https://www.genetrysolar.com/gs-balancers
  14. Finally got the Rev. C control boards / WiFi boards ordered. A LOT later than I hoped, but hey, they're ordered. Now hoping I didn't make any stupid mistakes on the boards...
  15. Expect no more than 2-3kw continuous max out of the inverter. That's just how it works πŸ˜‰. Pretty sure it's their latest model (likely will have a 10.3C or 11.0 control board in it). Older inverters used to have the AC output terminals at an angle--this one has them mounted straight up/down. Older inverters also had a fan over the transformer--this one has the "indication" of a fan on the label. Hard to say. If a wire goes directly from the transformer to the power output terminal, that'll tell you pretty quick that it's not filtered. Filter caps are 4.7uF ("476") and rated at least at 250vDC (most commonly 400vDC). For as small as the transformer is (likely an ASL1 / ASL2), one 4.7uF cap per phase will be beyond adequate.
  16. Well, depends what batteries/solar system I had already purchased / could easily find. Personally, I'm partial to 48v. Started my very first solar system @ 48v. Why, you might ask? You can literally get twice as many watts out of each MPPT charger...not to mention smaller/thinner cabling due to reduced amps, etc. Only downside is the need for specially-rated DC breakers; you can usually use just about any AC breaker (with the necessary amperage rating) at up to 32vDC. Thing about changing a GS inverter from 24 to 48v is that without a variac, verifying transformer wiring becomes difficult. Oh, and the fans will need replaced with our 48v fans. That being said, 24v should work fine. For that matter, it's a lot easier to find DC appliances that run on 12 or 24vDC. A lot harder to find stuff that runs on 48vDC.
  17. It got broken when I updated the SSL cert....for whatever reason, the SSL cert update bot ALWAYS rewrites the HTTPS security on that server--and I evidently broke it trying to restore it back to how I had it. Need to try to fix it...again... The "wifi.genetrysolar.com" server should force-redirect to HTTPS. However, there's a special clause that's the proverbial monkey wrench in the gears that's causing me a headache. WiFi is a LAMP stack on an AWS server slice. Was free for a year, haha. Nope. SquareSpace is such a closed system that it's not even worth using. It's easy to use if someone's selling shirts from China. Now, an IoT product? Nope, not even close. Shopify is a tad more flexible, but still difficult. As far as a redesign, we have our sights set high. Fully integrated solution, not a "thrown together bumble" of various ill-fitting plugins. All 3 sections (e-commerce, forum, and WiFi access) using the same authentication--i.e. no need for 3 separate user accounts. And all 3 sections tightly integrated into each other so tightly that you can't tell where one ends and another begins. Go to Genetrysolar.com -> log in -> My Inverters -> list of inverters -> click one -> current inverter status. Click another tab: bam, you're in the forum (already logged in). Yeah, there is no off-the-shelf solution for that...I am fully aware. Looks like we'll be switching the forums to Simple Machine Forums (SMF) at some point in the near future. Free to use, looks decent, very customizable, integratable, has importers for IPB, etc., etc.
  18. True. The other option is to utilize the help of various customers/forum members...which is the current plan, albeit moving at a bit of a slower pace. Can do SOME coding myself (the wifi.genetrysolar.com webpage is entirely written by me...spending DAYS on Google trying to figure out things step by step). I'd rather not, as it takes more than enough time to work on the inverter designs/boards/code, etc., etc.
  19. @dicksonMost of the issue with PJ transformers is an insufficient amount of wire on the core. But it does appear that the ASL9 core has a significant energy transfer efficiency problem.
  20. Just remember that both of us are very human, and highly capable of forgetting/losing track of customers. Until we can afford some CRM software......
  21. That is correct. Both were easy to come by, but neither are fitting the bill for us super well... Goal is <$30/month for a VPS that runs the website (including eCommerce), the WiFi server and the forums--all tightly integrated. No monthly subscription fees. But that requires web programmers who actually know how to make stuff work, not just stacking modules together.... ...yeah, that's why it's taking awhile πŸ˜‰.
  22. Ugh, LOTS of amps. Am working with a commercial customer that is trying to make 12kw 12v inverter--maybe you'll be able to buy an inverter off of them! However, that's crazy amps--you're talking past 1,500A @ 12v. Best case inverter efficiency is going to be under 70% simply due to the molecular electrical losses. That 31.2kw surge? Let's add 40% simply due to molecular electrical losses, and that's 31.2 * 1.4 = 43.6kw / 12v = a cool 3,640 amps. This jumps the gap between "stupendously difficult" and "electrically impossible." Why? At 12v, if the ENTIRE inverter resistance--battery cables, chassis wiring, MOSFETs, transformer, etc. is MORE THAN 0.0032 ohms (3.2 milliohms), it will be impossible to get 3,640A to flow @ 12v. Notice that I didn't say that any work was being done with this 3,640A. The inverter resistance will have to be far less than 3.2 milliohms in order to get any power to flow on the output side...otherwise the entire 40kw gets burned up in wire losses in the inverter, and no significant power is produced. Let's not mention that the FETs used in the 6k and 12kw GS inverters are rated at 3.5 milliohms on resistance. And they're very good FETs. At 48v, add only 20% for losses (probably way overcompensating), and that's only 780A. Far more manageable! Technically CAN support 12v on a 6kw from a hardware standpoint. But we definitely cannot recommend it--at least not with the current design. Full 6kw is 600A! Have heard that we have 1 GS customer with an inverter wired for 12v, and he's had it up to 5kw with no issues.
  23. This is how we started out...trying to improve a PJ inverter. But due to fundamental design challenges, we ended up making a completely original design for GS inverters. (Completely original ="no stock PJ design.")
  24. Umm...well...this is the Genetry Solar inverter firmware updates branch. These later firmware revisions have not been updated to the PJ channel.... ...but I need to do that. That'll also give you AC input / ATS / charge again (if your inverter is so equipped).
  25. The goal is to roll the website + inverter data server + forum into a single web host cost. But obviously as the current forum host isn't free (though it is a very nice setup), we likely will have to switch forum providers to a free one we can self-host. Don't want to get rid of the forum, that's for sure. But numbers are numbers.
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