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One valuable part of the DIY Solar forum is the Resource Section. This has many valuable links to Papers, Manuals and websites having to do with Solar and Batteries. https://diysolarforum.com/resources/ A sub-section of the resources is dedicated to resources for beginners that has a series...

A new phase in my solar journey Anyone who has followed me on the forum knows I have a passion for moving DIY solar forward and for helping people learn. I have had my frustrated rants (for which I apologize) but my intent has always been to be helpful and move the DIY solar space forward in a...

[RANT MODE ON] I can understand when people don't understand the terminology. I can understand when people don't understand the technology. I can understand when people ask questions that show they are clueless about solar & batteries. I would even say I enjoy helping these people...

There has been a lot of discussion about ‘Zero Export’ on the 18Kpv and I would like to summarize what is going on. General Points: The term ‘Zero Export’ is used throughout the industry to talk about preventing power from being exported to the grid. The reality is that Zero Export is a bit...

That seems pretty straightforward. Just tell them it is hooked to an EG4 24K Solar Air Conditioner and there is absolutely no connection to their grid. Then give them a link to the product. Part of me would want to be a bit more private and just tell them it independently powers an...

This is an offgrid design I recently helped someone do:

After Will's review of the Trophy server rack batteries, I looked up US pricing on several different 48V server rack batteries. Edit: Corrected it to Wh (Not KWh) EG4 LiFePower4 48V 100Ah – 5.12KWH (Feb 13 '22: $1499 + shipping - $0.29/Wh) Jackiper 48V 100Ah – 5.12KWH (Feb 13 '22: $1699 +...

Folks, When setting up an inverter, one of the more important safety things to get correct is the grounding and the neutral-Ground bond. All of the inverters have a grounding lug All of the inverters have a ground connection on the AC out. Some inverters have an AC in and when they do they...

I did not like the thin buss bars that came with a set of cells I purchased, so I decided to make my own. I purchased .25" x .75" copper bar from a local metal supplier, cut and drilled them and then electroplated them with tin (They are destined for a boat). I had never done...

Depending on the needs of the system, the EG4 18Kpv can be a reasonably straightforward install The above diagram assumes you are doing a whole-house backup and works for up to a 200A utility feed. The inverter goes between the utility meter and the existing breaker box. The inverter will...

What is the difference between inlaws and outlaws?

That is a fair question. If I thought my role was going to be ceremonial, I never would have agreed to it. I am a technical consultant and will be helping them on a wide range of topics based on my technical knowledge and experience in the DIY space. This could be about product...

Be sure to make the popcorn before they turn your power off!!! ;)

Here is an interesting chart on Cycle Life: Look at the charge and discharge rate. 1C for both and they still lasted over 4000 cycles before they hit 80%. In a typical solar installation, the charge and discharge rate won't be anywhere near that high. I can easily imagine a cycle...

Screenshot from wills video: All the neutrals go to one busbar - Clearly common-neutral. I have said for a long time that common-neutral is the best way to go for stationary systems.

What should you do if you are attacked by a gang of clowns? Go for the juggler.

This will be my last post on this thread. Please stay civil with each other. Disagreement is a good starting point for helping people learn, but if I believe someone is wrong, attacking them personally does not convince them to rethink their position. Instead, it pretty much eliminates the...

I love excuses to buy tools but that is a stretch.... I don't think I could sneak a Neutron Imaging system past my wife!! ?

I don't think anyone can deny that some systems were bricked with this message. It seems very likely it was done by Deye. (It seems highly unlikely it was a hack. If nothing more, Deye and Solark would be saying it was a hack) Almost by definition, it is related to Sol-arks Exclusivity...

The OP is not saying there is no reason for building your own battery. There are many reasons to do a DIY battery, the price being an important one. He is just pointing out that the trend line in the pre-built batteries is rapidly changing the price part of the build-vs-buy equation. The...

That was my first reaction as well. However, when I look closer at the data sheet, things seem more reasonable. The spec sheet says The 50A rating is at 830Vac. It is not specified, but at 240V it will be able to break higher currents and still meet the 30,000 electrical operations...

BTW: Here is a slightly updated diagram. 1) Added the current transformers. (These come with the 18Kpv) 2) Added the CANbus cable to the batteries (This also comes with the 18Kpv).

Sorry... I did not take video as I went, but here is a little bit about what I did: I am not an expert on any of this!! I learned as I went. This link has the Tinning instructions: http://transistor-man.com/electroplating_busbar.html Warnings: Do this at your own risk. Muriatic acid is...

Warning: I go full propeller head on this post!!! ? @Will Prowse just released a couple of videos about hooking parallel batteries together. One commenter claimed 4 batteries in parallel but hooked up 'Diaganaly' would stay balanced. 2 batteries in parallel with diagonal connections is...

A set of cells can only be top ballanced or bottom balanced. Not both. - If you top Ballance and then bottom balance, they will be bottom-balanced and they will NOT be top-balanced - If you bottom balance and then top balance, they will be top-balanced and NOT be bottom-balanced. For home...

There are people on the forum that disagree with me but I consider that chart garbage. The only thing you can tell with voltage is that the battery is nearly empty or nearly full. Trying to use voltage for anything in-between is a mistake

I am seeing posts of people wanting to build 48V systems with 5 or 6KW inverters and server rack batteries. This is a nice, clean way to build a system, but be aware of the current limits on a lot of the server rack batteries. I just saw this for the Pylontec batteries: A 5000W inverter...

Warning: The following explanation is very simplified, perhaps overly so. However, it is a reasonable first approximation way of thinking of it. The SCC, Battery and Load are all in parallel. If the voltage of the SCC is greater than the battery, it will drive current into the battery...

The new EG4 Gridboss has had a lot of press, but since it is not just another inverter or battery, it deserves a deep dive into what it is, what it does and how it benefits the customer. The bottom line is that it greatly reduces the cost and complexity of installations as well as adding more...

Thank you for alerting us to this @Will Prowse There are several fundamental problems around grounding on DIY projects. 1) Many of the inverter manufacturers do not provide adequate documentation on how the inverters deal with grounding. Growatt and MPP are among the worst at this (I have...

I would not think that would work well. The Wiring Unlimited resource you linked to had this pic: (This is page 19.... but the discussion before page 19 is also important to read. The key is to try to make the round trip resistance from the inverter to each battery and back the same for all...

NOTE: After learning more about the PowerPro battery and its capabilities, I have updated this and the follow-on posts for clarity and correctness. There has been a bit of discussion on paralleling the EG4 PowerPro battery. This and the following posts show many of the most common...

My take is that Will cares deeply about being an honest, transparent reviewer and that drives his actions accordingly. It is hard not to take the undeserved criticism seriously when it strikes at something he cares deeply about. Conversely, if he was the type that didn't care about what...

Yes.... There are 3 distinctly different places the energy can go: Grid, Battery or load. If none of those are available, the mppt cuts the PV current and shuts down production. This is pretty much the same on all systems... If there is no place for the energy to go the MPPT will shut...

Even with crappy leads, if you set the Power Supply to 3.65V (or whatever your target voltage is)....it will eventually get top balanced. Crappy leads will just make it slower. It is easy to say to go buy a better power supply, but for many people they don't see a need for it beyond the...

I did a similar set of calculations about a year ago. I was planning on a box with R30 all around (6" of insulating foam) It was surprising how little energy was needed to keep the batteries at an even temperature for even a 30deg C differential in temperature. I think I came up with...

I sent EG4 support an email with details showing why shipping without the bonding screws makes things worse unless they support common-neutral. Their response indicated that they felt shipping without the bonding screws made the system NEC-compliant in most cases. Their answer did not mention...

@Will Prowse is doing what he has always done..... giving us his honest opinion based on his experience with the product and knowledge of the field. He does not shy away from saying he does not like something.... and that is why I value his videos. I know I am getting what he believes...

One thing I don't like about the NEC is that they don't explain the "why" behind a lot of the requirements. This frustrates curious people like me that want to know why I am required to do something.

To everyone who might read this thread: Patience is the most important thing to have when you are top-balancing. Set your power supply to the target top balance voltage and leave it there. Keep in mind that with a 10A power supply you are using around 35W to charge cells that might have over...

I read through the instructible and here are my thoughts: It is not really practical for the typical home DIY, I would add more solar panels rather than add the complexity and complications of this design to get that ~5% to ~10% extra power. However, it is a very clever design. I like the...

As usual, the manual is nearly criminally negligent in any discussion of the grounding and bonding on the EG4 6000EX. :cautious: Based on the weight, I am guessing this is a low-frequency unit. Is this the correct model for it: Does the unit do dynamic N-G bonding? If so, can the...

I do not know if there is a standard for XT, but the rule of thumb for all plug types is that when something is unplugged you do not want the 'hot' prongs exposed. This will typically mean the female with the protected contacts is on the hot side(Power supply) and the male with the exposed...

There are many different reasons to DIY a battery so some people will be DIYing LiFePO4 batteries for the forseeable future. However, the prices and quality for pre-built batteries are now low enough that a lot of people no longer build their own. I am no longer building my own. The...

This is something I have wondered about for quite a while. They support Megafuses in all their gear and sell 48B versions of Megafuses, but they never really address the AIC question. Several months back I had the chance to talk to a Victron 'ambassador' about a system and he was...

EDIT: The Audit & Sizing spreadsheet can now be found in the "Resource" section of the fourm: https://diysolarforum.com/resources/system-energy-audit-and-sizing-spread-sheet.12/ In order to avoid any confusion, I will change the links in this thread to point to the resource rather than the...

Why couldn’t the pony sing cowboy songs He was a little hoarse.

I agree that it seems simple to derive everything from the basic formulas. In fact, I have never used the trick I posted. I just remember V=IR and P=IV and work everything out from that. However, like others have said, some people are not technically minded and need pneumonics or other...

I am going to answer a bunch of questions you did not ask. Let's start with some math: The three 12KW inverters can draw as much as (12000x3)/48 = 750A if fully loaded and the batteries are low. (Surge currents could be a lot higher). Consequently, the 3 batteries at 200A each are...

You are running into ignorance on the utility companies part. You are correct, the 6000XP is an off-grid inverter. It will not back-feed by design. It simply can't back-feed..... so they don't provide external CTs for it.

Please, folks, let's keep the discussion about the technical aspects. I am disappointed by the recent trend on the forum to make things personal. To me, it sucks all the fun out of participating in the forum.

I would think that most modern equipment with switching power supplies would never even notice 20ms...

Even multiple NG bond would not blow out boards

I just re-read the original post. I did not understand the description of the layout, but I realized he is asking about a situation with 5 batteries.... The 'diagonal' works ok for 3 or 4 batteries, but the more batteries added the less optimal it gets. The Halfway needs the symmetry of 4...

If I am following the description correctly, this is the solar configuration. That configuration would work very poorly. The 400W panels would probably create so much more voltage than the 200W panel that current would back-feed through the 200W panels. If the 200W panels were...

There are two types of arc fault. 1) Serial Arc Fault. This is most common when a connection is loose. This is also the type of fault the PV Arc Fault protection is required to stop. (A PV array has a LOT of connections both between the panels and within a panel). This type of arc can be...

The combined sustained battery current for 6 EG4 18Kpvs s would be (1500A). The surge current could be even higher. That is a crazy high number of Amps. If I were doing that setup I would keep each of the 6 racks separate and dedicate one per inverter. That keeps the max sustained current...

This will create significant NIMBY pushback for future battery installations. If I understand correctly, there are actually two different battery systems at Moss Landing. One by Tesla and one by another company. I wonder which it is. I also wonder what chemistry the batteries that are...

You won't hear me say LiFePO4 is perfectly safe, but it is far safer than NMC. Unfortunately, NMC and LiFePO4 are both lumped under the 'Lithium' heading so safety regulations that are appropriate for one are applied to both. A perfect example is battery spacing. There are rules put in...

I have been investigating Rapid Shutdown on the 18Kpv and would like to offer some clarity on the capabilities and situation. 1) The 18Kpv can do rapid shutdown out of the box using the integrated Rapid Shutdown Initiator. When triggered, the inverter will shut down the AC output and the...

To be complete, here is a bit more detail:

The N-G bonding should be done one of two ways in an off-grid system. OR I would personally do the bond in the breaker box. (Why count on a relay when you can hard wire the bond with a jumper)

OK.... I wrote up a top-ballance tutorial and put it in the resource section. https://diysolarforum.com/resources/tutorial-top-balancing-lifepo4-cells-using-a-low-cost-10a-benchtop-power-supply.65/ Please provide feedback.

That is the intent. The idea is that the inverter is between the meter and the main breaker box. Unless the grid goes down, this hybrid inverter runs in parallel with the grid (Both the grid and the inverter can supply power). If the inverter is not generating enough power, the grid will...

Folks!!! The OP is talking about the 6500ex, not the 5000ES. That is probably why he titled the thread "Newer models of EG4 6500ex are built without the bonding screw" It may be that the 6500 has similar trace issues, I don't know. However, let's make sure we are all talking about the...

The daisy chaining like @Brett V describes is one of the two styles of PV frame grounding. One thing to keep in mind is that the NEC requires the ability to remove one panel without disrupting the grounding of all the other panels. Furthermore, the wire is required to be one continuous wire...

The busbars that China sends all seem to have the Bend/Hump in them. I have always installed them with the hump up. But I recently saw a pic of someone that put the hump down. That got me wondering..... is one-way better than the other? (Yes.... I am on lock down and getting board). I...

Wow!! I started the thread as just a fun little question but it has turned into an interesting discussion of possible videos for Will. I like it.

BTW: If you have a windy location, you can get away with a lot lower wattage turbine than solar. Assume you get 5 hours of max solar per day (average) and 15 hours of wind per day (average). In those conditions, you need 1/3 the wattage of wind turbine than you do solar. At my hunting...

Let's back up a bit to understand the problem and understand the terms. All inverters have a bank of large capacitors tied parallel to the DC battery inputs. When the battery is first connected to the inverter, these capacitors appear as a dead short to the battery, and a huge surge of...

The announcement of these changes significantly alters the grounding and bonding options for the EG4 6500EX. Consequently, the MPP LV6548 & EG4 6500EX grounding and bonding resource I had previously posted has been removed and replaced with these two resources...

I am not ready to give up on democratic capitalism either. There is no better system..... but like all systems it can be corrupted. Back to my original statement: " For the most part I have learned that the NEC makes rules for good reason, but this sure feels like they were influenced by...

Same answer as your other post: I used to want breakers everywhere, but have come around to using fuses for anything needing 150A and above. If a 150A safety device pops, it is a big event that means something catastrophic happened. If a circuit is designed that can occasionally pop a 150A...

I can't speak for other forum members but I have only been recommending removing the screws in particular instances. In particular, I only recommend it when there are two inverters stacked and even then I have recommended it be removed from only one inverter. I don't think I ever recommended...

I top balance to 3.65V even though I charge them to a lower voltage. The theory is that I don't want them to get to the top balance voltage during normal use. However, if I am honest with myself I have to admit that if the BMS balancing system can't keep them balanced this won't help for...

I saw a cute trick for manipulating Ohm's law on one of Mike Holt's video. It can also be used with Watt's law. To remember the circles easier, drop the math operators from the circles and view it spatially:

For me, it has been a very long learning curve. My formal training was in electrical engineering, but my career was all in digital circuits and SW. The EE degree gave me the electrical basics... but nothing about solar or batteries. My professional career helped me learn to think like...

OK Here is my fee: You are an expert on something...... Go find a way to help someone with your expertise.

Lets do some math. I assume these are new cells. New cells generally come at ~40% SOC. 16 280Ah Cells in parallel will need .6 X 16 X 280 = 2688 Ah to fully charge. At 20A this will take 2688/20=134Hrs to fully charge. Yes, it is normal. Keep in mind that at 3.3V 20 A is only 66W...

The argument that the cost of panels has diminished the importance of MPPT is very valid, but MPPT certainly still has a place in the industry. A cost analysis that assumes available space for panels is unlimited or one that assumes the panels can be well positioned can easily miss some of the...

With 16 LiFePO4 cells, you can get 24 volts a couple ways: Edit: Updated 2P8S image

I just talked to Battery Hookup about this BMS and got a lot of great info. They do parallel bank hookups all the time They tested one of these BMSs for a week at 100 amps without seeing a problem. He says he finds that the price of higher amp BMS goes up so fast that it is lower overall...

Electrons do not carry energy!!! ???

The answer depends on how the 18Kpv is configured. One scenario is this: Loads: 1K Battery: 13K (That is assuming the batteries will take the full 200A max charge current the 18K can do) Export to the grid: 1K Total: 15K Now let's assume your battery is full and not taking current: Loads: 1K...

The simplest use case for the FlexBos 21 would be a totally off-grid system with just PV Battery and generator. (Configure for ‘Microgrid in order to use the generator on the Grid Port) This is a higher power Off Grid system than the 18Kpv at a lower price

Here is an exchange I just had with the Aliexpress Smart BMS Store: A couple of things: 1) This is claiming the current rating for charge is 250A. (I would still de-rate by 40-50%) 2) I did not realize there was a daly 'official' store. I am going to find it and ask them the same question.

Why worry about it? If you're battery is full by noon and the charge controller shuts down, who cares?

@Will Prowse , I am one of those old-fart electrical engineers and I can tell you that any EE claiming they have not made their share of mistakes and burnt a few things out are either lying or have never actually built something. My 3rd day in the first job out of collage, I burnt out an...

For those of you following this thread: I have learned more about the PowerPro and it's capabilities that I did not understand before. Consequently, I have updated the four original posts with new (and hopefully clearer) information.

Anything and everything is acceptable after the city inspector leaves

Folks, There have been many discusions about run-away cells and I have fielded a few questions about them so I though a resource about the subject might be a good idea. I wrote something up for a resource but would like a review before posting it. The following are the 7 pages of the...

Why do dogs make bad dance partners? They have two left feet!!

I assume that is 2000W Yes. The SCC will just not take the excess power. Doing some quick math, if 6 panels get you 1400W peak then you are getting around 1400/1920 = .73 or 73% of the rated power (this is not an uncommon event). Assuming the trend holds, 9 panels will peak out at...

I had not seen it before. It does look interesting. It looks like a knock-off of the Victron Smart Shunt. (I wonder if "TBD" was a placeholder for a reseller name and they just left it? ?)

Could you provide a link to one of the DC openers you are looking at? It would help us answer your questions on how to hook things up. As far as sizing goes..... let's do some math. 1.25HP is 932W. Let's round up to 950W. Lets assume it takes 15 seconds to open the garage door and 15...