Epever TracerBN + Lifepo4 + Pure Sine Inverter Restarts

[localboast]

Looking for some guidance as I really don't know what's going on here.

Setup:
SCC: Epever Tracer 4215BN
Storage: 24v 200ah Lifepo4 with 100a BMS
Inverter: 2000w Pure Sine
Cables: All sized correctly (I know this will be asked)

My SCC and Inverter are connected directly to the battery terminals (with properly-sized fuses in between).

I have the SCC set to USER mode with Battleborn's Lifepo4 settings (and have confirmed with my battery maker that these are correct).

Setting up the EPEVER Solar Charge Controller

The Epever MPPT solar charge controller has become a popular option for many customer applications. Find out how to set it up here!

battlebornbatteries.com

What's happening is that no matter what I set the Boost (absorption) to on the SCC, my inverter will quickly restart/brown-out (and beep twice which the manual says nothing about) when I hit the Boost value (I've tried 28.2 - 28.8).

The inverter has a High Voltage Protection of (30.0V+_0.3) so I should be safe there.
The inverter is never running above 200w.
The MT50 display will show OVD Error when the battery is full (which is fine).

I'm simply just trying to figure out why the inverter momentarily dies when my batteries are fully charged (and then over and over while there's still sunlight). Any ideas here would be AMAZING.

Thanks!

 

[Bobert]

Check for a bad connection on all cables and connections between the battery and inverter. Especially if you have any points where more than one cable is mounted under the same lug. It seems unlikely that your charge controller has anything to do with the problem you are having.

 

[blammo585]

Looking for some guidance as I really don't know what's going on here.

Setup:
SCC: Epever Tracer 4215BN
Storage: 24v 200ah Lifepo4 with 100a BMS
Inverter: 2000w Pure Sine
Cables: All sized correctly (I know this will be asked)

My SCC and Inverter are connected directly to the battery terminals (with properly-sized fuses in between).

I have the SCC set to USER mode with Battleborn's Lifepo4 settings (and have confirmed with my battery maker that these are correct).

Setting up the EPEVER Solar Charge Controller

The Epever MPPT solar charge controller has become a popular option for many customer applications. Find out how to set it up here!

battlebornbatteries.com

What's happening is that no matter what I set the Boost (absorption) to on the SCC, my inverter will quickly restart/brown-out (and beep twice which the manual says nothing about) when I hit the Boost value (I've tried 28.2 - 28.8).

The inverter has a High Voltage Protection of (30.0V+_0.3) so I should be safe there.
The inverter is never running above 200w.
The MT50 display will show OVD Error when the battery is full (which is fine).

I'm simply just trying to figure out why the inverter momentarily dies when my batteries are fully charged (and then over and over while there's still sunlight). Any ideas here would be AMAZING.

Thanks!

This reminds me of a guy's YouTube video where he changed his LifePo4 setting back to User and set the Boost and Equalize to 14.2, and this stopped his inverter from beeping and restarting. But you say you've changed the Boost setting, and that still didn't work. I don't know apples from oranges, but did you change the Equalize to match? Also, he changed his Equalize time to 0 mins and knocked the Boost time down.

 

[localboast]

Check for a bad connection on all cables and connections between the battery and inverter. Especially if you have any points where more than one cable is mounted under the same lug. It seems unlikely that your charge controller has anything to do with the problem you are having.

Thanks, I'll double check this but the timing of the "restarts" is just too... perfect with the SCC hitting Boost, I literally watch the voltage creep up to my Boost setting on the Inverter's display, and it freaks out and restarts/browns-out right when the voltage is hit and my SCC stops PV input.

This reminds me of a guy's YouTube video where he changed his LifePo4 setting back to User and set the Boost and Equalize to 14.2, and this stopped his inverter from beeping and restarting. But you say you've changed the Boost setting, and that still didn't work. I don't know apples from oranges, but did you change the Equalize to match? Also, he changed his Equalize time to 0 mins and knocked the Boost time down.

This SCC doesn't officially support Llithium however Will Prowse and many others have used the USER mode with lithium. I cannot turn off Equalization entirely sadly, but I do have it set to the same as Boost and the Equalization Duration set to 0 (so effectively off).

It genually feels like the sudden change in voltage when the SCC goes into Over Voltage or Ful battery makes the inverter have a tiny flicker, enough to cause my loads on the inverter to power off, restart, or brown out (stay on but not actually working).

 

[Bobert]

This reminds me of a guy's YouTube video where he changed his LifePo4 setting back to User and set the Boost and Equalize to 14.2, and this stopped his inverter from beeping and restarting. But you say you've changed the Boost setting, and that still didn't work. I don't know apples from oranges, but did you change the Equalize to match? Also, he changed his Equalize time to 0 mins and knocked the Boost time down.

If your battery is entering high voltage cutoff it may spike in voltage momentarily if it doesn’t have much load. This could trigger high voltage protection. You should be able to see this happen with a meter. The reading on the charge controller might not be accurate.

 

[blammo585]

Thanks, I'll double check this but the timing of the "restarts" is just too... perfect with the SCC hitting Boost, I literally watch the voltage creep up to my Boost setting on the Inverter's display, and it freaks out and restarts/browns-out right when the voltage is hit and my SCC stops PV input.


This SCC doesn't officially support Llithium however Will Prowse and many others have used the USER mode with lithium. I cannot turn off Equalization entirely sadly, but I do have it set to the same as Boost and the Equalization Duration set to 0 (so effectively off).

It genually feels like the sudden change in voltage when the SCC goes into Over Voltage or Ful battery makes the inverter have a tiny flicker, enough to cause my loads on the inverter to power off, restart, or brown out (stay on but not actually working).

Here's the link to the YouTube video I was watching. Sounds like he was experiencing the same as you.

Also, I think these controllers do support Lithium now but they have to be updated. Not that it matters if you have to turn around and put it back in User mode.

 

[localboast]

If your battery is entering high voltage cutoff it may spike in voltage momentarily if it doesn’t have much load. This could trigger high voltage protection. You should be able to see this happen with a meter. The reading on the charge controller might not be accurate.

Think this is it, the video posted below indicates this as well and this is my exact issue.

Here's the link to the YouTube video I was watching. Sounds like he was experiencing the same as you.

Also, I think these controllers do support Lithium now but they have to be updated. Not that it matters if you have to turn around and put it back in User mode.

Thank you for sharing! This is exactly what I'm seeing, however my settings are literally the 24v equivelant of his settings in the video (which are 12v). I guess I'll keep trying to knock the voltage of the Boost/Equal down until my inverter doesn't reboot? I do wonder however what the lowest voltage I can set safely in there is for lifepo4....

 

[blammo585]

Think this is it, the video posted below indicates this as well and this is my exact issue.


Thank you for sharing! This is exactly what I'm seeing, however my settings are literally the 24v equivelant of his settings in the video (which are 12v). I guess I'll keep trying to knock the voltage of the Boost/Equal down until my inverter doesn't reboot? I do wonder however what the lowest voltage I can set safely in there is for lifepo4....

It also makes me wonder if the inverter itself plays a part in the problem. Maybe some are more tolerant than others.

 

[localboast]

It also makes me wonder if the inverter itself plays a part in the problem. Maybe some are more tolerant than others.

It certainly might, I've been talking to my buddy about it as well who just-so-happens to be having the same problem with his new Lifepo4 setup (totally different components than me however). I've sent him this thread so hopefully some solution comes up that doesn't require spending.

After some very light research, it seems that most inverters have greater than 30v over/high voltage cutoffs, the lowest we found in our research being 30.5 (again, cut this in half-ish for 12v systems). The reputable inverters seem to be around 33v. Mine is 30v. That being said, I can and will keep trying to lower my boost/equal voltage to see if that does it (as indicated by the gentleman in the video above), however I do wonder if it still SCC or even BMS related (as I've tried lowering the boost/equal voltage in my troubleshooting, and the inverter would still restart as soon as the [new] lower values were reached)?

BMS is 100a, and there's no way I'm touching that. My load never exceeds 300w.
SCC could be the issue with how it handles the change in modes? IDK enough about SCCs, just a guess. But the issue happens when the SCC hits Boost/absorb voltage (28.8v). Perhaps it briefly switches charge modes and that causes a "hiccup"? Again, there's no way to disable Equal charge voltage on this unit, on the current firmware at least. I simply set Equal to the same as Boost voltage and set Equal Duration to 0.

Still investigating, but thanks for the leads so far!

 

[blammo585]

It certainly might, I've been talking to my buddy about it as well who just-so-happens to be having the same problem with his new Lifepo4 setup (totally different components than me however). I've sent him this thread so hopefully some solution comes up that doesn't require spending.

After some very light research, it seems that most inverters have greater than 30v over/high voltage cutoffs, the lowest we found in our research being 30.5 (again, cut this in half-ish for 12v systems). The reputable inverters seem to be around 33v. Mine is 30v. That being said, I can and will keep trying to lower my boost/equal voltage to see if that does it (as indicated by the gentleman in the video above), however I do wonder if it still SCC or even BMS related (as I've tried lowering the boost/equal voltage in my troubleshooting, and the inverter would still restart as soon as the [new] lower values were reached)?

BMS is 100a, and there's no way I'm touching that. My load never exceeds 300w.
SCC could be the issue with how it handles the change in modes? IDK enough about SCCs, just a guess. But the issue happens when the SCC hits Boost/absorb voltage (28.8v). Perhaps it briefly switches charge modes and that causes a "hiccup"? Again, there's no way to disable Equal charge voltage on this unit, on the current firmware at least. I simply set Equal to the same as Boost voltage and set Equal Duration to 0.

Still investigating, but thanks for the leads so far!

I believe there are several threads here about Epever controllers that talk about this same issue. Considering your friend has this same issue with different equipment, it makes me wonder is it more in the charge settings than it is the brand? But then again I keep seeing this pop up with Epever.

 

[fratermus]

The MT50 display will show OVD Error when the battery is full

I think this was the tip-off. Voltage spikes when the BMS disconnects charging and the Ep is too slow to avoid overvoltage. This doesn't happen when it is able to finish Absorption without the BMS cutting off; current just tapers off.

If we stop the BMS disconnect (lower charging voltage until cells rebalance so runners stop triggering cutoff) I think the problem will go away.

I do wonder however what the lowest voltage I can set safely in there is for lifepo4....

Many of us charge to 3.45Vpc (27.6v for 8S) with a token absorption. Offgrid Garage has demonstrated that 3.4Vpc (27.2v) will charge to ~full given enough absorption time (~4 hours at 0.2C rates, if I remember correctly).

 

[localboast]

I believe there are several threads here about Epever controllers that talk about this same issue. Considering your friend has this same issue with different equipment, it makes me wonder is it more in the charge settings than it is the brand? But then again I keep seeing this pop up with Epever.

Yea, at this point - as mentioned below, I think it has to do with the Lifepo4 charge settings vs the BMS & inverter itself. Not so much the brand, but testing still underway.

I think this was the tip-off. Voltage spikes when the BMS disconnects charging and the Ep is too slow to avoid overvoltage. This doesn't happen when it is able to finish Absorption without the BMS cutting off; current just tapers off.

If we stop the BMS disconnect (lower charging voltage until cells rebalance so runners stop triggering cutoff) I think the problem will go away.

Many of us charge to 3.45Vpc (27.6v for 8S) with a token absorption. Offgrid Garage has demonstrated that 3.4Vpc (27.2v) will charge to ~full given enough absorption time (~4 hours at 0.2C rates, if I remember correctly).

This sounds accurate in terms of what is unfolding. Looks like it's gonna be a game of "how high can I set the Boost (Absorb) voltage without the Inverter panicking".

Gotta determine the max Boost (Absorb) Duration accepted by this unit, and start at 27.2 I guess. currently I have it set at 28.8 with a 30 minute duration, but I'm assuming I'll have to go to 27.2 (or just north of it) for a much longer duration given my 2x 200ah. Math!

 

[localboast]

My buddy shared the following link:

Voltage spikes with MPPT near absorbtion. DC to DC also having issues at absorbtion. - Victron Community

community.victronenergy.com

Adding to my last post, this is deff looking like a "your results may vary" situation depending on the hardware involved. I'm going to try setting my Boost (Absorb) juuuuust above my Float and just max out the duration on the SCC. See where that gets us.

 

[fratermus]

Looks like it's gonna be a game of "how high can I set the Boost (Absorb) voltage without the Inverter panicking".

We might reframe it as "how low can I set the Absorption voltage and still get consistent charging to the SoC I want in the time available?"

Gotta determine the max Boost (Absorb) Duration accepted by this unit, and start at 27.2 I guess. currently I have it set at 28.8 with a 30 minute duration, but I'm assuming I'll have to go to 27.2 (or just north of it) for a much longer duration given my 2x 200ah. Math!

Max Absorp duration on the BN model is 180 minutes, IIRC. I'd probably set it to that then start watching what the bank is still accepting when the 3 hours is almost up. Lots of folks around here use 3-4% of capacity as a good cutoff point. That'd be 6-8A with your bank size.

Dunno if I muddied it up, but lowering Absorption voltage doesn't have to be a permanent change. Once the cells get back into line and stop tripping the BMS protections you can start creeping up on the Absorp voltage again. It's a bit like working with livestock where you walk slowly to avoid spooking them.

By the time you get the cells up to 3.5Vpc there may be no absorption duration required at all, assuming the soft-ish charging rates we usually see with solar. Note: the minimum duration on the BN is 10mins IIRC.

Let us know what you decide and how it works out. We're all learning together.

 

[localboast]

Well it's been months and no matter the settings I choose on the charge controller I still have the same problem. I've resulted to using a UPS to keep the 24/7 stuff running (so it doesn't die when the voltage spikes and the inverter restarts). Should I just try a controller that "officially" supports Li at this point? Seems like this one doesn't know how to handle the voltage when it disconnects at %100 SOC.

 

[localboast]

Maybe spoke to soon, after I made the last post I changed my boost (absorb) and float to 27.6 and max out the boost (absorb) time. Hoping the max boost (absorb) time of 3 hours on the BN is enough to keep my cells balanced, still testing. But no more over voltage spikes/inverter resets as of now!

 

[Benando]

Maybe spoke to soon, after I made the last post I changed my boost (absorb) and float to 27.6 and max out the boost (absorb) time. Hoping the max boost (absorb) time of 3 hours on the BN is enough to keep my cells balanced, still testing. But no more over voltage spikes/inverter resets as of now!

Hi Localboast, I have a similar problem with my Epever 5415 that you have experienced. Did those final changes cure the problem of voltage spikes/inverter resets?