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I pretty regularly weld with my Victron Multiplus 24|70|3000 units (now using 240 split phase but for a long time I just used one @ 120v). I've wondered the same thing whether the sharp changes in current demand will reduce the life-expectancy of the units, but so far so good. (About 18 months...

I wanted to start this thread so folks have a place to compare real-world numbers about their generator efficiency. This data is from two generators which I run exclusively on propane. Up to 2022-11-10: Champion 100263 (Nominally a 3400 watt generator) After 2022-11-10: DuroMAX XP9000iH...

Some things I've learned about the DuroMAX XP9000iH - hopefully some of this will help other folks: Similar Generators This generator is very similar to the following generators which can be used (with a grain of salt) as a reference when looking for helpful reviews, alternate manual...

This is just plain false in many cases. For example, I'm in the PNW, US near bellingham (not quite 55 degrees north, but still a fairly northern latitude) and I have my system sized (roughly) for my loads in the winter such that I fairly rarely need to run the generator. 4KW panels, 14KW...

Well, my understanding is that the current trend is solar panels are getting cheaper and cheaper relative to the total cost of an installation. Other costs such as labor, mounting/racking, power electronics, physical space used, etc then dominate. Under those conditions, saving up-front cost by...

Attached is an updated EVE LF280K model with the new terminal style. Both FreeCAD and Step file formats are included in the zip archive. The terminal geometry itself is copied from @Ron-ski's model on https://diysolarforum.com/threads/sketchup-drawing-of-new-eve-lf280k-new-style-cells.45761/...

It certainly seems to behave like a cutoff. My testing procedure involves the following settings; Then I confirm it's charging; Then I stick the temperature probe in a thermos with ice and salt to bring the temperature below freezing; At which point the controller and my bench power...

I'm guessing that many other folks - like me - have also accidentally shorted in reverse their power supplies while top balancing such that somewhere between -12v and -56v flowed through the power supply. When this happened to me, sparks flew and subsequently the power supply stopped working...

Not sure why (almost) everybody thinks I need "advice" here. I'm at ~48.6 degrees N so I know about seasonal variations in production (though maybe not as intensely as @upnorthandpersonal) - and yes my system is arguably oversized for the rest of the year too. That's not the point of this...

That won't work. Voltage drop is a function of amperage so there will be times when the panels are cold and not-yet really producing much power (or where the batteries are close to full), but may be close to full voltage. With the 150v max controller you should do 3S, not 4S. 4S with those...

Am I understanding correctly that this means you disconnected the batteries from the Epever unit before disconnecting the solar panels from it? I believe this is not recommended and may even be dangerous to the Epever unit...

I ended up starting to play around with this concept... Welded bus bar: After tin electroplating: Installed: (might still add heat-shrink in the middle) Hoping to make the next one turn out a bit cleaner, but that's the idea anyway ?

I'm curious if you've done the theoretical math on the energy involved in the start up surge for those devices vs the amount of energy in the super caps? In the past I've wondered about various strategies involving capacitors to deal with current surges and concluded that the total power stored...

You need to review the manual for your inverter. It probably has a section labelled something like "Parallel Operation in Single phase" which will describe how/if the inverters can be connected to create a split phase system. If possible, it will involve a special data cable run between the two...

Personally, I suspect that the distance between the inverters will create a subtle (but maybe irrelevant) out-of-phase effect where the two sine waves will be slightly off depending where in the system you measure - or possibly everywhere as a function of the signal lag over the data cable. I...

@Aussie_Pete have you tried selecting the "Off Grid" tab in that PVGIS tool you linked? It can estimate how much of the time your batteries will be empty/full... e.g.

I've uploaded an alternate model that includes the Step file format at https://diysolarforum.com/threads/starting-a-parts-library-using-freecad-as-a-design-tool.26546/post-649507 (Credit still goes to @Ron-ski for modeling the actual terminal geometry.)

I'm also watching this carefully since - once my cells arrive - I'll also be setting up a microcontroller to publish metrics to InfluxDB from mine. :)

Actually, correction; it doesn't even matter if the panels are cold. They could blow up your SCC any time your batteries get full.

Couple corrections here... The 50A-100A versions, including the 60A version, are shown on their website. https://www.epsolarpv.com/product/44.html (Linked from "Products" under "Solar Charge Controllers" -> "Solar Power Station Controller".) The AN controllers are sold in several different...

Complexity! Panels/cells in series/parallel need to be matched. The edge cells within each panel couldn't be triangular and be in series with the other cells without bringing down the current output of the whole string of cells. In some cases, two or more triangular cells could be put in...

I don't have a link handy, but there's at least one other thread on here about extreme EMP protection strategies. I think the conclusion was that it's very hard to predict how much EMP protection you'd need and basically impossible to test whether you've done it right ahead of time. I would...

When you start asking about "Best R-value", my mind goes to vacuum based insulation strategies. Almost certainly impractical, but fun to think about. :unsure: In practice, this is why you need the math @sunshine_eggo is pointing to. Engineering is almost never about "best" - but "good enough"...

Thanks! Combination... I TIG welded two pieces of ~1/8"x3/4" copper bar stock at a 90° on to the end of one of the bus bars that came with my battery cells. The tin I used was from a roll of lead-free (and non-rosin core) solder. You can buy a 1lb roll from most big hardware stores. I...

I believe it's not that uncommon for US (headquartered that is) generator manufacturers like Champion and Westinghouse to do just that - send warrantee repair parts on the basis of a support call explaining a problem. e.g. bad weld in a exhaust manifold, malfunctioning switch, etc. Albeit...

I think that was sarcasm where you're agreeing with me and just making a funny comment, but in case the rest of my reply didn't make it obvious, I'm not saying ampacity is useless. I'm just explaining why it may not always match up with what the voltage drop calculators say. To put it another...

Using a shunt that is somewhat close to the right range for your loads is best though. i.e. Try not to use a 1000a rated shunt for loads that are never >100a because it won't be very accurate. I believe that in general the larger the shunt ampacity, the lower the precision of the measurements.

Ethics are always situational. Take cannibalism as an example; as a human it seems fairly clear-cut, but zooming out and imagining yourself as a spider or preying mantis the female's choice to eat their mate is totally the right thing to do. For those species' individuals (which are already...

I'm also curious what the best way to source genuine (definitely compatible) MC-4 connectors is. For those suggesting hard-wiring panels, I will point out that there's a safety argument for having at least one (easily accessible - for ground-mount this can just be the series connections at the...

Disclaimer: I'm not an electrician, but I think I'd be inclined to: use a small breaker box as a combiner box to parallel the two inverters - instead of the bus bars have a larger breaker box with a main breaker as your "main panel" feed your nearby outlets using breakers in the "main panel"...

That's cool @parody! For others curious how this is done, the main special sauce here seems to be the use of this plugin: https://grafana.com/grafana/plugins/agenty-flowcharting-panel/ - which allows a Drawio diagram to be embedded/augmented in a Grafana dashboard.

Presumably, because it's the price point the market will bear for the convenience of a ready-made mid/high-end battery - and there's not enough competition for that segment of the market to drive the price down further. Especially since DIY and budget batteries erode the size of that market...

I had this same problem recently (also running two Overkill 8S BMS') and a full restart of the BMS solved it. I don't know if this is the best way, but here's what I did; Disconnect and kill any clients of the Bluetooth module Disconnect all loads/charging Disconnect Bluetooth module connector...

Without the answers to @timselectric's first question it's hard to say, but the simplest answer will probably be to get/make a longer RJ45 cable (a regular straight ethernet cable) and use it to put an MT50 display somewhere easier to read. The cable can be quite long - the manual says up to 50...

Wow, that's awesome! Seems like we might be starting to see a trend in terms of running gas being cheaper per kWh. Converting that into a comparable numbers: $5.64 ($ / gal) / $0.96 ( $ / kWh) = 6.558 kWh / gal 6.558 (kWh generated) / 33.41 (kWh total energy) = 19.6% efficiency

Obligatory IANAL, but they can't revoke the GPL license on the previously released source code. So if someone wants to keep maintaining a similar app as open source (still under GPL of course), they can fork off version 1.1.1 as a starting place...

It's somewhat minor compared with the other issues that have been pointed out, but you also should reconsider the mounting orientation of your charge controller (likely the DC-DC charger, and inverter as well). If you're ever going to use them close to their rated power outputs for any length...

My understanding is that they're just talking about using multiple BMS in parallel on the same cells. There should be no issue using 4 separate BMS in parallel each with their own 16s sets of cells - which is what I believe @HRTKD was referring to.

Hi Folks! I've been playing with various off-grid systems for a while now, but just starting to get into building my first LiFePO4 system. With any building/design project, one thing that really helps me think through the spatial and material requirements is being able to visually assemble the...

Reducing rolling resistance, air resistance, and the rotating mass of the wheels should also be considered. Possibly even with unconventional support and propulsion - depending on the surfaces this device needs to operate on (and the weather conditions it should operate in)... * Very light...

These are great! Very reassuringly solid connections/action. Don't skimp on safety hardware.

We'll call the time where a system is neither all the way full nor too close to empty: "coasting" IMHO, time spent coasting is one measure of how well an off-grid system is balanced in terms of production capacity, storage capacity, and usage. Lots of ways to look at this, but; If your...

Well, I tested with the voltage divider. I guess I'd call this mixed results. :) It could be that breadboard connections aren't good enough for what the balance leads need to be doing...

Or, similarly, you might be able to avoid the superstructure/air-resistance necessary to support the lens, by instead pointing the solar panel down and making the body of the vehicle into a reflective collector that focuses a larger area of solar onto the panel. (Though you have to be careful...

Not all BS... there are still several reasons to wear masks today - even improvised ones worn incorrectly; Socially normalize mask wearing such that immunocompromised folks aren't ostracized for continuing to wear masks (correctly) - for instance during flu season. Practicing explicit...

You folks might be interested in the undocumented Epever modbus command 0x43 that I've described my reverse-engineering of here: https://gist.github.com/symbioquine/95ba2abaf046c8e034b41e4cf3c334a9 That's how the MT50 remote displays get most of their data with fewer read/response exchanges...

CO Sensor (continued) It turns out that the "new" replacement generator DuroMAX sent me under warranty is actually 10 calendar months older (2021/06/01 vs 2022/08/02) than the first one I got. Interestingly, the CO sensor modules are different between the two generators. The mid-2022 model is...

It might be possible to "power up" a fridge or AC, but no system will run those things for very long at a $500 price point.

I went with 0.25"x1.5"x36" oxygen free copper bar stock clamped between pieces of HDPE plastic. I like how thoroughly overkill it is from an ampacity standpoint and that I can drill exactly the holes I need.