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Struggling with basic LiFePO4 settings in Epever Tracer

Hello Friends!
Can somebody explain me how XTRA/Tracer works with 'boost' settings.
I have the following settings, attached. With boost 14.2; boost reconnect 13.3, boost dur 10min; and float chg 13.6.

Once I power on XTRA N it keeps charging untill 14.2 and rests there for 10min. Than float is activating and voltage drops gradually to 13.6.
Than I connect load and voltage drops to 12.83, but float mode is stills active. I wonder why controller simply ignores "boost reconnect 13.3" and still operates at float, or it is designed this way?
Only power off/on helps to activate boost again.
 

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Is the end of your graph after you power-cycle the controller? Looks like everything bumped back up.
Are you disconnecting PV input before power cycling it?

If your load is dropping voltage to 12.83 the controller should switch to the boost charging cycle, or at lease bump output to service the load and charge. You're not getting output current to support your load?

What is your PV array and how many volts input do you usually see? I'm not seeing PV input voltage there.

Remember, your controller measures voltage on the bus with any voltage drop from load, or excess voltage from charge current. It's not always real accurate. Put a DMM on your battery posts, or utilize a shunt meter.

I have seen wonky system voltages on the controller as well, sometimes it takes time to stabilize, or if there are other charge inputs that will throw it way off. I thought my two EPEver charge controlers - small and large/portable array and roof-top, but they really don't. The charge current from the smaller one will put the larger one in float/standby, or it will even cut the input PV voltage - some refer to this as PCM mode.

Having more PV input voltage - 50-70% of rated capacity - seems to work better as well. Trying to input a low parallel-PV wired input never seems to work as well with these.

Boost voltage might be a little low - I started there but moved it higher for just these scenarios.

Do you also have a BCM monitor/app? I tend to rely on it more - it shows charge and discharge, individual cell voltage, etc. It's much more accurate than the charge controller. And if you have any distance to your battery, you'll get a different voltage at the controller depending on what the load and charge levels are.

What is your load Ah? 310Ah battery?

Just throwing out a lot of thoughts here...
 
Browneye,
Thanks a lot for a feedback.
I have this solar system for my camper truck. Use it occasionally for going out.
System is lifepo4 310ah 12v, Xtra N 30A, and 2*200w Sunpower custom 30 cell foldable panels in series, but for this particular test I used 1 200w foldable panel from AE. BMS is deligreen same as Daly with Android app.
Of course I use this rule - first power up mppt and then connect solar panels.
I'm not using controller load terminals and connect loads to BMS.
Figures on Daly bms app under load little higher than mppt pc software is showing, but still lower than 13.30 which is boost reconnect.
Maybe I had to keep this voltage under 13.3 more time to activate boost? I've waited maybe 30minutes or so. Is it possible that float also has a duration time?
Like I said under load mppt is pumping current untill 13.6V regardless the load. In my case it was 7-8 Amps.
I have this Xtra N second year and initially used similar settings from above and did not care a lot, because I had only freezer 12v connected. But recently decided to put default for lifepo4 which resulted BMS to shut before mppt stops charging. So after this decided to go back in details again.

I also have my old tracer bn 10, will try to the same test.

The reason why I started playing with the settings is that I had more moderate settings with boost 13.8, and this year I've started using induction stove, and I felt that mppt is not working on maximum with 2 200W Sunpower pannels in series.
I've also purchased another brand 200w foldable and connected in series to other two, but it turned out that new pannel has different internal resistance and started overheating, even after I put diode. So I've connected it to my old tracer
 

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Nothing sounds or looks out of the ordinary.
And yes, if boost voltage is too high with any unbalanced cells, it's not uncommon for bms to terminate charge for over voltage. One cell can reach full charge and shoot up, shuts off all charging.

I dunno, it should reboost when bus voltage drops below boost setting. I'm not getting that either. I would suggest contact EPEver for a warranty claim, but I'm not sure they're responsive. Ideally you test another one to find out the one you have has bad circuitry, is failed in some way.

OTOH, I have had a similar issue, and power cycling puts it back into boost mode.

You could hookup one panel to the 10a controller and see how it behaves. It should put out pretty close to its 10a rating in sun if the battery can take charge. It might be a bit over-paneled, but it should still put out its max.

Are the settings image after 'READING' the controller settings? Maybe you're not getting them saved?
The green bar battery current shows spiked up - but the controller is reading 12.8 battery volts?
 
Hello Browneye,
Today after some more tests I figured out that it takes 5 minutes for Xtra N to return back to boost mode once the voltage drops to 'boost reconnect voltage'. So this process is not immediate. I even increased boot reconnect voltage to start this process faster, but same result - 5 minutes.
Did not have time to test it on tracer bn, so far.
 
That makes sense. You don't want it bouncing all over the place in just seconds.
I couldn't believe it just quit working, although that has happened to a few unlucky souls. :giggle:

Trying to get help from them is hit and miss as far as I've heard around here. There's a language barrier issue as well from time to time.
Overall I like mine, they're much cheaper than victron which seems to be the gold standard - but they're nearly twice as much. I often thought if mine just didn't work right I would replace them with victron. I have a dc-to-dc orion and it's great. Nice product, nice BT interface.
 
Hello everyone,

I have a solar charger Epever Tracer6420AN 60A 200V and a battery-pack Joyvoit BW5KW 100Ah 5KW Lifepo4 48V system with an Epever Ipower-plus 5KW 48V-230V offgrid inverter
I managed to readout the battery settings and solar charger settings and would like to optimize the solar charger settings.
In the following table you see all settings of the batterypack (16 cells) on the left side.
On the right side you see the settings of the solar charger, when corrensponding settings there is a arrow (--->) symbol in between the fields
The current settings and desired settings are found on the far right side

My question is if these desired setting values are reasonable/practical and I hope one of you experienced guys could give me some advise;

read settings from battery;read settings from Solar charger;
Cell Over VoltageValuecurrentdesired
cell OV alarm V3.60
cell OV protect V3.65
cell OVP release V3.40
cell OVP delay time mS1000
Charge Over Current
CHG OC alarm A105battery capacity Ah200100
CHG OC protect A110equalization charge V58.4056.80
CHG OCP delay time mS1000boost charge voltage V57.6055.80
Discharge Over Currentfloat charge voltage V55.2054.00
boost recon charge V52.8052.00
DSG OC alarm A105boost duration m120120
DSG OC 1 protect A110equalisation duration m120120
DSG OCP 1 delay time mS1000
DSG OC 2 protect A150
DSG OCP 2 delay time mS100
SCP delay time mS300
Pack Over Voltage
pack OV alarm V57.60--->over voltage disconnect V6457.30
pack OV protect V58.40
pack OVP release V54.40--->over voltage reconnect V6054.40
pack OVP delay time mS1000
Charge and discharge Over Temperaturecurrentdesired
CHG OT alarm C55
CHG OT protect60
CHG OPT release55
DSG OT alarm C60
DSG OT protect C65
DSG OTP release C60
balance treshhold V3.40
balace delta Vcell mV30
sleep Vcell V3.15
delay time min5
Cell Under Voltage
cell UV alarm V3.00
cell UP protect V2.60
cell UVP release V2.80
cell UVP delay time mS1000
Charge and discharge Under Temperature
CHG UT alarm C5
CHG UT protect C-10
CHG UTP release C5
DSG UT alarm C-15
DSG UT protect C-25
DSG UTP release C-15
Pack Fullcharge Voltage V56.00
pack fullcharge current mA2000
State of Charge
SOC low alarm %
10
Pack Under Voltagecharge limit voltage60.0056.20
pack UV alarm V48.00--->low voltage reconnect50.4048.00
pack UV protect V41.60--->discharge limit voltage42.4041.60
pack UVP release V44.80--->low voltage disconnect44.4045.20
pack UVP delay time mS1000
under voltage warning V48.0048.00
under voltage warn recon48.8048.80
External annd solar charger:
charge pack < 57.60V (OV alarm) and > 54.40V (OVP release)= 56,80V

Any advise, check or verification is greatly apreciated

Maikel
Bangkok Thailand
 
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This seems unnecessarily low. 3.6V is certainly safe voltage to operate. 3.55V would be a conservative release.


same here (x16)

Thanks a ton Mr Sandals,
So 56.8V as pack release as I calculate, correct?
The values on the right side for the charger are all reasonable (equalization, boost. float, etc.) ??
 
equalisation duration m120120
The values on the right side for the charger are all reasonable (equalization, boost. float, etc.) ??
Equalization is LFP killer. Time to zero. Good catch.

56.8V / 16 = 3.55Vpc is a very conservative number. If this is annoyingly low (you'll know when you are annoyed that you BMS is off), 3.6V works too.

boost charge voltage V57.6055.80
I am a conservative charger because i have a big battery and don't need more than gentle 100% charge. I like 3.45Vpc (x16 = 55.5).
If your cells behave, try 3.5Vpc if you feel the need. See how it goes and reevaluate.

I float at .02V below where my cells settle an hour after full charge to prevent micro cycling (charge, settle, charge, settle (needless thrashing)). Mine settle at 3.35V so i float at about 3.33Vpc.
If you continually have loads running in full time use and want a higher SoC, 3.4Vpc is used by a lot of others.
 
Equalization is LFP killer. Time to zero. Good catch.


56.8V / 16 = 3.55Vpc is a very conservative number. If this is annoyingly low (you'll know when you are annoyed that you BMS is off), 3.6V works too.


I am a conservative charger because i have a big battery and don't need more than gentle 100% charge. I like 3.45Vpc (x16 = 55.5).
If your cells behave, try 3.5Vpc if you feel the need. See how it goes and reevaluate.

I float at .02V below where my cells settle an hour after full charge to prevent micro cycling (charge, settle, charge, settle (needless thrashing)). Mine settle at 3.35V so i float at about 3.33Vpc.
If you continually have loads running in full time use and want a higher SoC, 3.4Vpc is used by a lot of others.
Thanks so much, appreciate your feedback.
Equalization off/0, i kept 3.60V as boost charge voltage.
I hope I understand all now, these are my conclusions;

charging:
cell overvoltage protect release 3.60V = pack OVP release 57.60V battery --> overvoltage reconnect 57.60V solar charger
--> cell boost charge voltage 3.60V battery --> boost charge voltage 57.60V solar charger
cell charge limit voltage 3.63V battery --> charge limit voltage 58.00V solar charger
cell float voltage 3.48V (0.02V higher as recommended) battery --> cell float voltage 55.68V solar charger
cell boost reconnect charge voltage 3.33V = boost reconnect charge voltage 53.20V solar charger
cell settle voltage 3.50V = pack full charge 56.00V battery --> settle pack voltage 56.00V

protection:
cell overvoltage protect 3.65V = pack OVP 58.40V --> overvoltage disconnect 58.40V solar charger

Is it ok that the charge limit and overvoltage protect are so close (0.4V) together? I kept "pack OV protect V" as a guidance for this, set in the battery-pack. I also kept the battery "pack setting Full charge" 56.00V leading to calculate the settle, float and boost voltages? Is this correct or should I change this full charge setting in the battery pack and keep 3.4V as float (I would like a higher SoC)?
 
Is it ok that the charge limit and overvoltage protect are so close (0.4V) together?
This will soon be apparent depending on how well behaved your cells are up at that voltage.

I kept "pack OV protect V" as a guidance for this, set in the battery-pack. I also kept the battery "pack setting Full charge" 56.00V leading to calculate the settle, float and boost voltages? Is this correct or should I change this full charge setting in the battery pack and keep 3.4V as float (I would like a higher SoC)?
Ya lost me on this. You're close and can tinker with these to see what works for YOUR usage and YOUR battery.
 
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