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41
Inverters & Grid Integration / Re: Interfacing wind turbines to the grid
Last post by SparWeb -
Watching it functioning for a day, and there are several improvements to be made before a permanent device can be built and trusted to run long-term.

1) Microcontroller is too wimpy to run its built-in relay.  The "Feather" microcontroller is compact, but has a very limited power supply.  Trying to drive a relay (even one designed to be compatible with the Feather) is pushing its ability.  Every fourth power cycle or so, the relay drops out immediately after it pulls in.  The system has to reset and try again.

2) The timing is set up to vary the length of its cycle.  This isn't necessary.  I don't need the potentiometer / adjustment knob.

3) Using a timer to control the time connected is not ideal.  Whatever amount of time is set, there's a situation where the time won't be appropriate.  On a very windy day like this, there is no need to cycle the timer every 20 minutes.  On a gentle wind day, maybe 20 minutes is good.  On a day with no wind, there's still no need for a timer.

4) Orient the control solely to the detection of the diversion load activity.  I've already built this in, and it's a factor in activating the buck controller.  I should exploit this more fully.  Instead of stopping the export with a timer, I can just make the microcontroller monitor the diversion load's activity, and stop the export when the diversion load stops.

5) Plainly obvious cable clean-up!

6) Need a series resistance in the DC cables to the microinverter's MC4 connectors.  I think about 1 Ohm will help the microinverter settle down it's MPPT algorithm into an operational phase.  I see it always stuck in a testing phase where it randomly varies the current.  It's trying to compute a pattern to guide its MPPT program, but with a steadily regulated 48.00v coming out of the buck controller there's no pattern to see.  A 1-Ohm resistor will give it something to lock in on.  Some energy will be wasted as heat, but what's the diversion load doing anyway?
43
Inverters & Grid Integration / Re: Interfacing wind turbines to the grid
Last post by SparWeb -
Success!
My first prototype* did its thing without any magic smoke escaping.

I haven't posted about this for several months because I spent February building the kit and deciding to drastically simplify it compared to the system I described and sketched for you all before.  In late Feb I had parts of it working while I refined the code.  In March the WT started making funny noises and then my charge controller quit. So it's been out of service until this week.  That paused the development of this idea for 3 months. Also, instead of using discrete devices like FETs or SSRs to regulate the battery current, I've chosen to use a buck controller instead.  It got me to the testing phase quickly.

The buck controller converts the 50-60V from the battery into a flat regulated 48.0V.  Feeding a microinverter with that has some limitations (I'll describe later) but for now I'm satisfied that the microinverter won't run away to infinity or go berzerk.  When plugged into 240V AC the microinverter's output went happily to the AC feed in my garage.  I happened to have my car plugged in at the time, meaning that most of the 300W being exported actually went into the car.  :) First time my car was charged from WIND.

The buck converter didn't have any trouble either.  It was windy and as long as wind power was coming in, the battery was at float about 54V feeding the bucker enough that it maintained 48.00V without a twitch.  This sounds great at first but there's a detail that makes this a small problem.  With 6 Amps going through the buck controller it's little fan was running on the heatsink, but its little MOSFETs were below 35C (95F).

Later, while still running the buck converter + microinverter combination, I shut down the wind turbine for a while.  The charge controller stopped, too, and while the microinverter was still running the battery voltage dropped to about 50V.  At that point, the buck converter's output started to sag below 48v.  The microinverter actually responded to this, interestingly.

Microinverters have a start-up procedure that they do every time they start up.  The one I'm using has a 5-minute start where it watches the incoming voltage before it connect any current flow.  It's probably making sure it's not responding to a spurious voltage pulse.  Once current does start to flow, the microinverter varies the current randomly.  It's strange to watch because the current swings from 2 to 6 to 4 to 5 to 3 to 4 to 6 and basically wanders all over the place.  Eventually I figured out that it's building some kind of "performance table" in its memory.  Once it's built the performance table then it knows how the "solar panel" responds to change in current.  This makes sense because solar panels have a varying power curve. Full sun, partial sun, clouds, changing angle during the day, all affect them.  So it seems the microinverter will keep trying to calculate what this performance table looks like until it has one that makes sense and can predict where the MPPT point is.  While it doesn't have a solution to this problem, it keeps shifting current up and down randomly. 

For all the time the buck converter was feeding the microinverter a tightly-regulated 48.00V, the microinverter couldn't do anything with the current that would affect the voltage.  This gave it nothing for the MPPT algorithm to use and it doesn't stop randomly testing the current/voltage changes.  During the time the WT was continuing to charge the battery and it was held at float, the buck converter could maintain its 48.0V, preventing the microinverter to settle into its full power MPPT operation.  Then, when I did shut off the WT, and the battery voltage sagged, this is what allowed the battery voltage, and thus the output of the buck controller to finally start varying with current.  Then the microinverter got the answer it was looking for.  Once that happened, it's output went from fluctuating between 100W to 300W to suddenly rise to a nearly steady 600-630W.

* AKA "box of random bits"
46
Forum Help & Suggestions / Re: Adding a dark mode
Last post by eColumbus -
I found 2 dark Themes that are supposed to work with this latest version of ElkArte. I tried to install them and both of them give me an error. They are themes made long ago but one of them was supposedly updated to work with this version of ElkArte.
I will continue to try. I want a dark mode myself.

Ed
47
Electronics, Controllers & Monitoring / Re: Tristar TS60 Repair attempt
Last post by MaryB -
Quote from: SparWeb – on
The little wire shunt didn't work.  Shrug, worth a try, and not much too lose.

Yes with some light and a magnifying glass I can see that under the DIP switch panel there's still a lot more crap under there probably corroding the rest away, maybe other pins are about to go next.  A proper fix is only to de-solder the whole DIP switch block (16 pins) and put a new one on.  That wouldn't be too hard or expensive, so I think I'll try it.  First just for the challenge and second for the chance to restore a devise that has otherwise worked well for many years.

I tried prying the heat-sink off but the FET's are stuck on tightly and I didn't want to break anything.  Nonetheless Morningstar tells me it's possible and provides instructions to do it in a manual for ambitious folks who want to de-solder and replace burned out MOSTFETs.  That doesn't seem to be my problem but if the heat sink can be removed that would help me access and replace the DIP switch panel.

A little 90% isopropyl alcohol dribbled on the transistor tab/heatsink interface in a way that lets it run down down behind the tab will help loosen them. Heat sink compound gets old and dried up and replacing it wouldn't hurt either!

Unless you are skilled in desoldered something on a double sided board I wouldn't try it. Better yo break the dip switch case apart and nibble it down to just pins sticking thru then remove one pin at a time. At the casino we had boards with them that were in the path of drink spills and the boards weren't high quality. So we destroyed the switch and removed a pin at a time then use solder wick(Chem Wik brand for best results!) to clean each hole being very careful how much heat is applied. If you lose a bad don't panic, you can look on the schematic/follow the traces and run a tiny wire between points trying to follow the original trace path. Did a lot of that at the casino when drink spills ate traces off boards. A slot machine CPU board was a $10,000 replacement so we patched until it was impossible to patch any more  :o
49
Electronics, Controllers & Monitoring / Re: Tristar TS60 Repair attempt
Last post by SparWeb -
The little wire shunt didn't work.  Shrug, worth a try, and not much too lose.

Yes with some light and a magnifying glass I can see that under the DIP switch panel there's still a lot more crap under there probably corroding the rest away, maybe other pins are about to go next.  A proper fix is only to de-solder the whole DIP switch block (16 pins) and put a new one on.  That wouldn't be too hard or expensive, so I think I'll try it.  First just for the challenge and second for the chance to restore a devise that has otherwise worked well for many years.

I tried prying the heat-sink off but the FET's are stuck on tightly and I didn't want to break anything.  Nonetheless Morningstar tells me it's possible and provides instructions to do it in a manual for ambitious folks who want to de-solder and replace burned out MOSTFETs.  That doesn't seem to be my problem but if the heat sink can be removed that would help me access and replace the DIP switch panel.
50
Storage, Batteries & Management / Re: AGM Battery Resting Voltage
Last post by MaryB -
Quote from: SparWeb – on
On the most trustworthy true RMS meters:
Meterman 37x: 12.94+12.96+12.95+12.97 = 51.82V
Fluke 374 clamp with leads: 12.9+12.9+12.9+13.0 = 51.7V

Earlier today I did some troubleshooting on the Tristar charge controller.  It was pulling 25Amps out of the batteries for a while in "Load control" mode during my tests, which has cut down the voltage from 52.0 a little.

So close to where mine rested... I would say nothing wrong...
51
Electronics, Controllers & Monitoring / Re: Tristar TS60 Repair attempt
Last post by MaryB -
That will work but MAKE SURE to clean every bit of gunk from under the switch. That is a double sided circuit board and gunk tends to eat the copper pads. If there are any electrolytic capacitors above that switch check then to see if any bulged and leaked and replace them... they have a finite life span...
52
Electronics, Controllers & Monitoring / Re: Tristar TS60 Repair attempt
Last post by SparWeb -
I think I can solder a little piece of wire across the DIP 2 pins and make it a permanently Closed switch.  Then the Tristar would work on 24v and 48v batteries, but I'd have to be careful if I wanted to do other bench tests on it, because a 12v test setup wouldn't work.
53
Electronics, Controllers & Monitoring / Re: Tristar TS60 Repair attempt
Last post by SparWeb -
The Testing manual guides you through several tests.  I had to re-do some because I didn't follow the instructions properly.
But the main obstacle I had was finding a suitable power supply for the tests.  They specified that the power supply needs to provide "18-20V" and be "current limited".  Well I really don't have a bench power supply that does that any more.  I spent some time cobbling together a few batteries that would give me about 24v to work with and then I connected an ammeter that has a fuse in it to provide the current limit.  After all that was set up, not before, I turned around and realized that I had a spare solar panel leaning against the work table all this time!  duh

Tristar_Test_2026-05-24.jpg

Above is the Tristar passing a battery recharge test.  I made it through all the tests and the Tristar didn't fail any of them.  Hmm.
I tried doing several things that didn't do any good so I won't waste your time describing them.

Out of ideas, I gave it a good cleaning while it was out and discovered a huge wad of gunk on the DIP switch panel.  Cleaning the gunk off I could tell that the gunk has oozed under the DIP switches too.  Since then I've been focused on figuring out if the DIP switches are the cause of all the problems.  At first I thought DIP 7 was the culprit, having the worst of the gunk under it.  Tried a few ways to clean under it more vigorously, but failed.  A long time later (I'm really slow it seems) I realized I could test for continuity on DIP switches easily.  Once I did that, it became obvious that DIP 2 is not closing when switched, and remains in the open state all times.  All of the other DIP switches went from open to closed when switched. 

Tristar_Detail_2026-05-24.jpg

From this I'm able to conclude that DIP switch 2 being stuck open causes the Tristar to think it's always in 12 Volt mode, even when set to 48 volt mode.  For a diversion charge controller to think it's set to 12V, but hooked up to a 48V system, it would indeed run the diversion at 100%, because it thinks the battery is overcharged.  It also explains why it passed the tests yesterday, because those tests only used 12V batteries.
54
Electronics, Controllers & Monitoring / Tristar TS60 Repair attempt
Last post by SparWeb -
TLDR: I haven't fixed it yet.  But I'm closer to knowing what's wrong!

Something went wrong with my TriStar TS-60 a month ago.  Probably while I was messing around with something else and connected the Sol-Ark inverter to the batteries while the Tristar was still connected.
I've already learned that the Tristar and Sol-Ark don't get along, but I forgot, and had a panicky moment running to the breaker to shut off the Tristar but the damage was done.  And since the Tristar was being forced to run its diversion load at 100% by the Sol-Ark at the time, I think shutting down the Tristar that way caused it to have a disconnect while it still had diversion load terminals energized. 

I knew something was wrong when I went to reactivate the wind turbine system.  The Tristar was locked into 100% diversion, even at modest battery voltage.  No change of settings would convince it to stop running the diversion load at full power.

A replacement Tristar is on its way (should be here soon) but in the meantime I wanted to see if I could fix the Tristar, or at least figure out what I'd done to it.

Helpful: The Morningstar website has a Testing manual AND at Repair manual for download.  These days that's almost unheard of.  The test manual has a series of procedures to follow to help you figure out what's wrong.  I'll follow up with a post about doing these tests, but right now I have to go and find where I left my cell phone...
55
Storage, Batteries & Management / Re: AGM Battery Resting Voltage
Last post by SparWeb -
On the most trustworthy true RMS meters:
Meterman 37x: 12.94+12.96+12.95+12.97 = 51.82V
Fluke 374 clamp with leads: 12.9+12.9+12.9+13.0 = 51.7V

Earlier today I did some troubleshooting on the Tristar charge controller.  It was pulling 25Amps out of the batteries for a while in "Load control" mode during my tests, which has cut down the voltage from 52.0 a little.
57
Storage, Batteries & Management / Re: AGM Battery Resting Voltage
Last post by MaryB -
My smaller 100ah agms rested at 12.6 volts...

have you measured at the batteries with a calibrated voltmeter? Cheap voltmeters can drift off calibration.

Another thing to check if the wire run between batteries and voltmeter is long and/or if it passes near any transformers... I had to use shielded cable to my Tristar TS-RM-2 meter(remote meter for the MPPT45/60 charge controllers) because it would pick up voltage when I transmitted on my ham radio and then stay reading high until I unplugged it for awhile.
58
Storage, Batteries & Management / AGM Battery Resting Voltage
Last post by SparWeb -
Last year I purchased a set of 4 Rolls S12-230AGM-RE batteries.  They've been installed since October and working great since then.  I don't have a problem but instead I'm observing something that doesn't seem normal (at least in my experience).

For the past month, the batteries have been "at rest" meaning there is no charge or discharge on them.  Also for the past month, I've noticed that their total voltage has remained at "52.0V" all that time.  I think I was expecting them to rest at about 50V, maybe a bit higher.  Converting to a per-unit measurement they average: 52/4 = 13.0V each.  Is this normal for an AGM battery?

Ruling things out:  The two different sources that could recharge these batteries (an inverter and a wind turbine) have been disconnected at the breaker and shut down, respectively.  There haven't been any unusually hot or cold temperatures here (Calgary).  The batteries power a little LCD voltage meter that's been displaying "52.0" plus or minus 0.1 all this time, but that's a phantom load, not something that would supply a charge.

I've consulted some data for these AGM's on the Rolls website's support pages.  I found a chart of open-circuit voltage versus SOC which suggests that 100% SOC has a resting voltage of 12.8 to 12.9V, which is getting close to what I see.  But that's for 25degrees C, and these batteries live at ambient temperature, which is more like 0 - 10 degrees C in the spring. I should add that I don't think these batteries really were at 100% SOC when they were disconnected. In early April, the temperature would have been about 5 degrees C, meaning the maximum SOC would have been about 90%.  If I made a prediction based on this information, I would expect 12.6V * 4 = 50.4V today.  The same charts show that self-discharge isn't a factor at these temperatures (which is great).

Does anyone see anything unusual about 52.0V?
(or 13.0V per battery, I should say?)
59
Forum Help & Suggestions / Re: Adding a dark mode
Last post by MaryB -
I have days when my sinuses are really hating on me that the sinus headache morphs into a migraine so light sensitivity too... to be able to easily flip back and forth...