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Epever charge controller dropping out of MPPT mode

Mine Epever 10A Tracer series does the same. I'm restarting it occasionally to get rid of the issue. Two 21Voc panes in series. From time to time I see it staying at 14V. Restart brings the voltage to 30+ volts and doubles the power.

A year ago trying to do a firmware upgrade, but IIRC - there was no firmware available for it.
 
The MPPT (Maximum power point tracking) algorithm seems very basic and it is. However it's a very, very precise and sensitive kind of basic. Given an ideal panel and sunny day the "high school" implementation will work fine. Given real world conditions where clouds arrive and reflect more sunlight for a few minutes, then cut most of it, then reverse every few minutes.... the MPPT process has what we could call "false knees" and "false elbows" which cause "algorthimic stagnation". Basically it backs itself into an oscillation around a "false knee" point far away from the actual power point. The "RESET" is a quick way to stop this persisting.

It's also a dirty hack. It's not elegant and ... well, it's what most do. The gains from more advanced MPPT will not offset well against the cost of more micro-controller power and... software engineering shows us that the more complex you make something the less reliable it is.
will it help the algo. if the software knows how many watts a pannel is and what it mmp voltage is


lets say 300 watt pannel
8.2 amp
39 v open cirud
mmp 32 v
 
The problem is that the maximum power point is constantly changing depending on how the light is hitting the panel. And the voltage can be radically different when you have a shadow on the panel.

A typical MPPT hunt will start at the full open circuit voltage, and apply a small current, then measure the resulting watts. It then increase the current a tiny bit. Did the wattage increase? If yes, then increase the current a tiny bit more. Did the wattage increase? If yes, increase current again. Keep repeating until the wattage falls, then reverse. Lower the current. Did the wattage increase? IF it did, lower current again. If the wattage drops, revers again, and increase the current.

The routine works just fine if the amount of light changes slow, and you have no shadows. But when something moves and a shadow appears on the panel, the maximum power voltage is going to change a lot. And it can take a while for it to find the new power point. And with a small shadow, the maximum power curve might have a second knee point where the bypass diodes take over and the current can increase a lot more at a lower voltage with a column of the panel that has a shadow being bypassed. Many MPPT controllers will only find the higher voltage knee, not a lower one. And as the complain here shows, a simple MPPT search can go bad and run to maximum current and drag the voltage down. The Victron way of resetting every 15 minutes and doing a faster hunt might make more power in tricky conditions. But it might make less power over time if the light is steady and only changing with the earth rotation. A slow tight search will stay closer to the max power point while the reset totally moves out of it and has to find it again.

Midnight Solar charge controllers have a few choices for the search routine. But it could take many days to find what works best for your panels and location. My cheapo BougeRV charge controller seems to search fairly fast, but I do not se it doing any reset like the Victron. But I do see it swing over 50 watts past the max power point, both up and down in voltage, about every minute or two. And that is at 700 to 1,400 watts with 2,000 watts of STC rated panels. In reality, that 50 watt swing is small, just 7% at 700 watts, and less than 4% at 1,400 watts. And when it drops by 50 watts, the next step is back up in wattage to the peek again. Over time, they claim it average at better than 98% of the true maximum power. I don't know how true that really is. On the good side, the only time I see it pull the panels down to battery voltage is when the sun is very low in the sky.

I would love to try a Victron on half my array and compare them for a few days and see which really does make more power and by how much. Are they worth the cost difference?
 
My tracer 4215BN 40 amp mppt worked fine last 2.5 years. Now fails to go to boost phase. Battery stays at 13.3 v. I have the MT 50 meter. Any ideas?
 
My tracer 4215BN 40 amp mppt worked fine last 2.5 years. Now fails to go to boost phase. Battery stays at 13.3 v. I have the MT 50 meter. Any ideas?
Is your boost reconnect a couple of tenths above 13.3? What happens when you put a large load on the system?
 
array voltage is 73.7; amps: .9; shown by MT 50; MT 50 also shows battery voltage of 12.4 and 4.9 amps going to battery. So atleast mppt is working?

power is from 4- 100 watters wired in series at 48 volts; this is now before sun hits panels. Power goes 65 feet in 10 gauge wire. MT 50 programmed for lead acid battery. Have six golf cart batteries wired series parallel at 12 volts. Battery Voltage now is 12.5. I'll put a 100 watt load on later when voltage gets up to 13.3. Couple of days ago I did just this and it stayed at that level. Normally, in past two years, epever 4215 bn tracer mppt would give the double blink for full pv charging and for full battery within an hour or two. And in full sun with 100 watt load battery would get about 20 amps. Thanks.
 
array voltage is 73.7; amps: .9; shown by MT 50; MT 50 also shows battery voltage of 12.4 and 4.9 amps going to battery. So atleast mppt is working?

power is from 4- 100 watters wired in series at 48 volts; this is now before sun hits panels. Power goes 65 feet in 10 gauge wire. MT 50 programmed for lead acid battery. Have six golf cart batteries wired series parallel at 12 volts. Battery Voltage now is 12.5. I'll put a 100 watt load on later when voltage gets up to 13.3. Couple of days ago I did just this and it stayed at that level. Normally, in past two years, epever 4215 bn tracer mppt would give the double blink for full pv charging and for full battery within an hour or two. And in full sun with 100 watt load battery would get about 20 amps. Thanks.
When the sun is higher in the sky, check the panel volts and amps as well as the battery volts and amps again. I am in So Cal and it is 10:15 am here now and my 100 watt panels are putting out around 16.5 volts at about 3.45 amps each. 4 of them in series would be 66 volts at 3.45 amps and making about 220 watts. Maybe 16 amps of charge current on a 12 volt system. Your 73 volts at under an amp looks like very weak current. Low sun might do it, but I am thinking maybe a failing connection making some high resistance. When MPPT tries to pull more current, the voltage tanks, so the max power point ends up at very low current and you see high voltage.
 
An update on this
It seems my epever tracer ANs get bored and drop out of producing energy all together 2 of them did this today
1695770038813.png
1695770064727.png

I unplugged my solar power cables and repluged them back in and went from this:
1695770156707.png
To this:
1695770190137.png
 
I was considering Epever when looking for a better SCC, but it's reports like these that have made me pony up instead for a Victron. It is shocking how much more energy the Victron 100/30 produces compared to my old Renogy 30A (both MPPT). I never saw it hit higher than 290W on a 400W system with the Renogy, but the Victron produced up to a peak of 380W within a couple of days of installing it. This isn't exactly a scientific study, and time will tell if I continually see higher output with the Victron, but so far (it's been about 2 weeks) it is showing this to be the case. I don't know if it has to do with better internal connections or better MPPT tracking or both, but it's money well spent IMO.
 
I was considering Epever when looking for a better SCC, but it's reports like these that have made me pony up instead for a Victron. It is shocking how much more energy the Victron 100/30 produces compared to my old Renogy 30A (both MPPT). I never saw it hit higher than 290W on a 400W system with the Renogy, but the Victron produced up to a peak of 380W within a couple of days of installing it. This isn't exactly a scientific study, and time will tell if I continually see higher output with the Victron, but so far (it's been about 2 weeks) it is showing this to be the case. I don't know if it has to do with better internal connections or better MPPT tracking or both, but it's money well spent IMO.
Yeah I am considering switching to SRNE (mostly because I am broke) or just waiting and living with it till I can afford to replace them all with Victron.
 
I was considering Epever when looking for a better SCC, but it's reports like these that have made me pony up instead for a Victron. It is shocking how much more energy the Victron 100/30 produces compared to my old Renogy 30A (both MPPT). I never saw it hit higher than 290W on a 400W system with the Renogy, but the Victron produced up to a peak of 380W within a couple of days of installing it. This isn't exactly a scientific study, and time will tell if I continually see higher output with the Victron, but so far (it's been about 2 weeks) it is showing this to be the case. I don't know if it has to do with better internal connections or better MPPT tracking or both, but it's money well spent IMO.
I will be curious to hear how well it tracks over a few months. If it keeps making 20 to 30% more than the Renogy, maybe I will have to trade up from my BougeRV unit. My guess is my BougeRV and the Renogy are likely very close. I have certainly seen the MPPT tracking do some odd things and I never see better than about 90% of what my Enphase inverters are getting when I compare watt for watt of solar panel input. They claim 98% MPPT tracking, but I doubt it. But is Victron worth 3 x the price? Even pulling in 20% more power, it will take a long time to pay off that difference. And I just checked on Amazon, The BougeRV I have went up $10 to $149, and the similar rated Victron is now $307 so it is only a tick more than double right now.
 
I will be curious to hear how well it tracks over a few months. If it keeps making 20 to 30% more than the Renogy, maybe I will have to trade up from my BougeRV unit. My guess is my BougeRV and the Renogy are likely very close. I have certainly seen the MPPT tracking do some odd things and I never see better than about 90% of what my Enphase inverters are getting when I compare watt for watt of solar panel input. They claim 98% MPPT tracking, but I doubt it. But is Victron worth 3 x the price? Even pulling in 20% more power, it will take a long time to pay off that difference. And I just checked on Amazon, The BougeRV I have went up $10 to $149, and the similar rated Victron is now $307 so it is only a tick more than double right now.

Yes I’m curious also how it plays out over months, but winter is approaching and this is a camp trailer that will be under cover soon, so that will have to wait.

The Victron 100/30 I got retails for about $210, but the company I bought it from gave us 10% off when I asked about any coupons. Free shipping and I think they didn’t even charge tax. They’ve been a stand up company to deal with and this is my third purchase with them.
 
On my 4215bn's that's boost vs non boost that gets results like that. If I program it so that it is wide open all the time it stays high on the output. If I don't then it puts out full till boost "wears off" then goes low like that.
 
Its when the controller pulls down the panels to just above the level of the batteries
Been talked about on here before
Now I know what to look for, yes, I'm seeing it - but.
This plot is from this mornings sunrise. The PV voltage comes up to the battery voltage and is "clamped" there.
These panels are oriented true north, so even at this time of year, it take 30min before the panels are usefully illuminated.
The PV voltage remains at (approx) battery voltage, but at zero current.
(the PV current isn't rising as fast as usual, so I'm guessing it's pretty overcast).


1698177004841.png
 
It happened to me - stuck at low output. I saw it yesterday early when I was getting ready to hook up a second 4215BN. After disconnecting and reconnecting the panels, the delivered current shot up. Thought it would have corrected on its own as it was still very early.

Today I didn’t intervene until well after noon. Both 4215BNs were just delivering at most 250W combined and panel voltage was nearly the same as battery voltage. After turning the panels off then on, power went up to 800W. If I didn’t intervene today I don’t think I would have replaced what battery capacity I used up last night. I wouldn’t say that today is cloudy either. We have some high altitude haziness, but no formations I’d say are clouds.

The reason I went for the 4215BN was the passive cooling and the ability to take large wire gauge. This ‘bug/oversight’ is a big deal though.

I wonder if there is a command that can be sent to the controller to disable then reenable it so it starts hunting the MPPT from scratch from a high voltage level. IMG_9415.png
 
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I wonder if its a software issue. My 4215bn's are very old and have never been updated. Also I have never had the issues your having.
 
Decided to go check :)

I couldn't find any screen on the MT 50 display that showed a version # of the software its running. It showed a serial number but that was it.
 
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