epever hybrid 5kw HI , low voltage disconnect changing parameters

[Alan B]

HI ,I am having problems entering the LVD parameters setting ,at the moment the default is set at 43.2 volts
this seems very low to me ,[what do you folks think?]
I was hoping to up this to 48 volt [this is for 8 x 6volt cells ] 8KWH AGM batteries
But the interface wont let me change [after long press the up/down button]
has anyone else experienced this with Epever UP-HI 5000 RTU?
thankyou Alan

 

[Bruspark]

HI ,I am having problems entering the LVD parameters setting ,at the moment the default is set at 43.2 volts
this seems very low to me ,[what do you folks think?]
I was hoping to up this to 48 volt [this is for 8 x 6volt cells ] 8KWH AGM batteries
But the interface wont let me change [after long press the up/down button]
has anyone else experienced this with Epever UP-HI 5000 RTU?
thankyou Alan

Two things

Not used that one but on smaller models I remember the interface (PC or LCD) was a bit clunky and for instance you couldn't raise a LV disconnect above a LV warning

BUT

The trouble with LV disconnects is that the on load voltage for AGM can seem really low while still technically being allowed (check your battery curves)
A single LVD level that protects a slow discharge (say 44 in your case) will probably cut off with lots of charge left at High discharge
But you'll have plenty of time to intervene on the slow discharge case . .

 

[Alan B]

Okay thankyou Bruspark ,i need to look at my battery curves .
would you say the default setting of 43.2 volts maybe ok then ?

 

[Ucatchmydrift]

HI ,I am having problems entering the LVD parameters setting ,at the moment the default is set at 43.2 volts
this seems very low to me ,[what do you folks think?]
I was hoping to up this to 48 volt [this is for 8 x 6volt cells ] 8KWH AGM batteries
But the interface wont let me change [after long press the up/down button]
has anyone else experienced this with Epever UP-HI 5000 RTU?
thankyou Alan

Hi, i have the epever up-hi 3000, same as yours but 3kw version instead of the 5kw. Im using lifepo4 instead of agm. Have you tried using the 'user' setting instead of using the set 'agm' setting. This will allow you to set all the variables yourself. But as bruspark says above, another setting may need to be increased first before you can increase the LVD. Also, some settings will need to be a minimum of .5v higher than the other setting before they will be accepted by the inverters software. For eg, LVR (reconnect) will need to be at liest .5v above LVD. The inverter seems reliable so far, but a bit basic with the software. No shedule charging for example. This can be gotten round though.
No remote access, but this can be gotten round also too, i made a guide on how to do this if your interested:
https://diysolarforum.com/threads/e...remote-access-full-version.55951/#post-771631

 

[Alan B]

thankyou ucatchmydrift , I will have a look at the other settings then .

 

[Alan B]

sorry to labour a point , but in your opinion is the default setting of 43.2volt a bit too low for a low voltage disconnect
on a 48 volt system [AGM battery]. I imagine Epever have done it for good reason but to me it just seems wrong. thankyou

 

[Alan B]

forgot to mention , the mains power went the other day and batteries where taken down to 43.2
and thus a warning was issued . later the whole system then went out ..darkness.. sorry bruspark
have not looked at battery curves as i need my sparky mate to pop round and explain what to look at exactly .

 

[binky]

forgot to mention , the mains power went the other day and batteries where taken down to 43.2
and thus a warning was issued . later the whole system then went out ..darkness.. sorry bruspark
have not looked at battery curves as i need my sparky mate to pop round and explain what to look at exactly .

so if you had reset the voltage higher, then you would have been plunged into darkness sooner. As I understand it, the thing to avoid is too high a charge voltage, that's what can cuase those lovely battery fires we see on TV regularly these days.

 

[Ucatchmydrift]

forgot to mention , the mains power went the other day and batteries where taken down to 43.2
and thus a warning was issued . later the whole system then went out ..darkness.. sorry bruspark
have not looked at battery curves as i need my sparky mate to pop round and explain what to look at exactly .

Unfortunately i have not had any experience with agm batts, i have lifepo4 connected to my epever inverter,, but, googling agm voltage charts i can see that 0% soc is 42v and 10% soc is 46v, so id guess that 43.2v is probably less than 5% soc. As far as i remember, going below about 50% soc on a lead acid or agm (is yours agm gel?) is very bad and reduces the life cycles quickly. Personally i would have the LVD at 48.2v which is 50%. Yes, you only get 50% of the battery, but, unfortunately, agm etc are old tech.. You need twice as many or, ideally 3 times as many as you would think, as to get them to last reliably (according to most, but not all) for say 10 years, you cant really dischaege them down to more than about 80% soc, which sucks. Hence why id sell them and build your own lifepo4 and have them last 20 years discharging them down to 10-20% to be safe, and charging to about 99% soc, or wherever the voltage starts to increase rapidly...

But, 43.2v is way to low for LVD in my opinion. Youll kill them quick doing that if you hit that voltage a number of times, especially if left at that soc for a while..

 

[Ucatchmydrift]

And also like bruspark says above, you may hit that voltage pulling a large load, switch off the load, and the voltage will pop back up.. So, you may want the lvd lower if your hitting it regurly, but have the warning come on incase your at that (genuine) voltage and pulling a small load.. Be handy to know that the warning is happening though, hence why i have data sent into the house/mobile phone etc incase of a problem. You wont hear the inverter bleeping at you with the warning. With lifepo4 you have a larger range to play with lessening the chance of hitting lvd under large loads.. Unless you have a whole bunch of agms to take the large current lessening the voltage drops..

(you would have charge from grid come in below 50%soc for example, but you may end up charging from grid when pulling a large load by accident, so you could have it set to charge from grid until it puts in 10% for eg., accept, i think your supposed to fully charge agm/LA to 100% when you charge them else you again can damage the batteries! - another reason to go for lifepo4!)

 

[Alan B]

epever advised against smart lithium batteries for this inverter [dumb ones could of been used perhaps]
the other consideration was the price and I also think battery technology is developing and hoping the AGM will last
till another alternative appears on the market . thanks for the input I will have another bash at changing the LVD soon.

 

[Ucatchmydrift]

epever advised against smart lithium batteries for this inverter [dumb ones could of been used perhaps]
the other consideration was the price and I also think battery technology is developing and hoping the AGM will last
till another alternative appears on the market . thanks for the input I will have another bash at changing the LVD soon.

Lifepo4 are fine to use with your inverter, if its the HI model. I have the same, its just the older ones that dont accept lifepo4.. Its just that you cant plug in BMS comms from some lifepo4 into it as it only accepts some bms protocols, (which is what epever are meaning..) but, thats not a problem, as you dont need too... You probably wouldnt bother if you build a diy bank anyway, no need. Plenty of protection from the inverter and the bms itself, if you want bms data, you can use home assistant to view it directly. For eg £2300 for diy 14.4kw lifepo4 that lasts 20 years worked out cheaper than LA batts.. All the ready build lifepo4 banks are just sooo overpriced its crazy. But good luck , dont drain the agms past 50% if you want them to last 6 years