Lux ac battery controller

EVandPV

Ah, Uhome batts must work differently to Pylontechs.

ianatkin

EVandPV said:

Ah, Uhome batts must work differently to Pylontechs.

I'm not sure they do and your suggestion makes sense.

I have the (utterly appalling) Aoboet app for the UHome batteries and, while it provides almost no useful information at all, it does suggest that the master battery discharges and charges faster than the other two in my stack, there is often a spread of several % between them. I had assumed it was because the master battery was weaker than the other two (I have no way of finding out what the SOH is or what the cell voltages are) but it is actually probably down to how they are wired, now you mention it. 

I wonder if it also explains why I can only get maybe 2-3kWh of my alleged 6.6kWh usable at 3kW before it drops to 1.7kW for the remainder 🤔

(Sorry for the rant hijack)

EVandPV

ianatkin said:

EVandPV said:

Ah, Uhome batts must work differently to Pylontechs.

I'm not sure they do and your suggestion makes sense.

Yeah if you look up google images for Pylontech stacks, they're pretty much all wired the way I described.
Pictures of the Uhomes are much harder to come by but the few I can find are wired from the top one to the inverter.

1961Nick

EVandPV said:

Verdigris said:

I was looking at the Lux importer's website and it seemed to imply that you could only attach 5 x 2.4 Pylontechs to even the largest inverter. Is that just out of date information re Pylontech, which I understand can be linked in parallel up to 16 units? Also there was no mention of 3.5 Pylontechs, which is what makes me think the information is outdated.

According to the Pylontech data sheet, the max is 8 modules per stack so 8 per inverter.
I'm pretty sure the Lux can take 8.

For the US2000C, Pylontech have increased the maximum pack size to 16 units. 

madswitcher

Hi Folks

I am new to this forum and battery systems and am trying to get a handle of what is happening to our new installation:which is a couple of weeks old.

We have 2 Lux Inverters each having 2 x 2.4KWH Pylontech batteries to give a total of 9.6KWH and have a couple of anomalies that I would appreciate some council on.

The first is that we have a 'phantom' consumption load of about 1KW that we cannot account for (consumption is about 1.6 KW when it should be a few hundred watts) : the thing is that it seems to only appear in the morning when the Solar Panels start to generate power and when the batteries have been drained overnight to 10% of their charge.  Export to Grid is disabled and the SolarBoost device is disconnected.

Any ideas?

The second question is about the behavior of the batters when charging from the PV panels.  Looking at the Pylontech front panels LEDS, one of the batteries in each chain seem to go off when the batteries are around 53% of charge.  This seems to imply that one battery is charged up and then the other when the first is fully charged.  Is this the normal way of working.  The 'Run' LED are all on on all of the batteries.

The good this that we tried out today is the EPS.  I have a local 'Spark' put all the vital circuits on a new Consumer Unit - Central heating, downstairs ring main, Internet modem and wireless and a small ring main in the lounge.  I threw the main house breaker and it flipped over seamlessly.  The Ipad app took about 10 minutes to get itself sorted but eventually caught up

Thanks for any help

Mike

Solarchaser

Welcome madswitcher, I have to say that's a strange arrangement you have, 2 inverters and 2 batts on each.
Was that your spec to be able to build up later?
I ask as you are limiting output on both inverters by having only 2 batteries, and with 4 in total it seems strange you would opt for two inverters. 
Are they set in parallel as master and slave?
And if so, do you see this consumption when viewing as the parallel graph?

I'd go and look at your CT clamps beside your smart meter and make sure the arrows on both are pointing into the house and not out to the grid, same for the clamps monitoring your solar array.

I also see a kick of consumption in the morning,  but assume its my bathroom heated floors kicking on.

Ianatkin,  my advice would be to ignore the manual and wire the batteries with positive on 1st batt and negative on last as this splits the current drawn across all batteries *fairly* evenly.
Having both connections on one batt means that batt will be getting a kicking and the one furthest away will be having an easy life.
That's not manufacturer specific, that's just electrical principles in my opinion. 

madswitcher

Hi Solarchaser - thanks for your reply.

The configuration is such because each Lux AC device can only source 3.6KW and I wanted more than that.  They are squirrel pod devices that work in parallel as a single device (master/slave).  I also wanted this config so that I can add batteries as-infinitum as prices (hopefully) go down in the future.

As far as I can see, the input/output power graph is only valid for the master device and this shows data for both of the devices.

Thanks for the tip about the CT clamps - I'll check them over tomorrow and report back  I assume that they are installed properly as the system is only a couple of weeks old. Also, we don't have a smart meter.  If I read your reply correctly, the arrows on the clamps should be pointing towards the Consumer Unit.  Is that for the Lux devices and the Solar inverter?

Regards

Mike

Solarchaser

Oh interesting,  you have the squirrels, id be interested in any details you have about them.

In particular it was said they wouldn't work with solar, but you have solar, so that must be false.
A cynical person... ok OK it was me, wondered if they were just normal inverters with an api running to say when to charge similar to what some of our forum users have done themselves. 

Regarding the clamps, all the arrows should essentially point to your solar panels, so yeah the grid ones towards your cu and the solar ones to the incoming solar.
If you have 2 solar array you can monitor them separately,  as that's what I do.
Master on one solar circuit and slave on the other.

What benefit is the squirrel pods if you don't have a smart meter? I thought it was to pick out the cheapest time for import?

Re the graphs, if you are looking on the online portal you only see them combined, but in the app you can see the individual inverters.

So with 2 batteries you will be maxing out at 2.5kw on both inverters for both charge and discharge.
I think you can convincingly make an argument for having 4 batteries on one inverter as a less arduous time for the batteries which will get 0.9kw max rather than 1.25kw they will be doing now.... just incase you need to justify the future purchases to the wife 🤔

madswitcher

Solarchaser,

I don't understand your statement about maxing out 2.4KW on each inverter.  Each  AC ESS inverter can charge/discharge a max of 3.6KW at a given instance (7.2KW system total since they behave as a single unit).  Having 2 x 2.4 KWH batteries on each inverter means that will do so for longer.  What point am I missing?

The end objective of getting the Squirrel Pods was to eventually flip over to Octopus and use their off peak deals, but to do that at the moment would be not be financially beneficial. 

EVandPV

madswitcher said:

Solarchaser,

I don't understand your statement about maxing out 2.4KW on each inverter.  Each  AC ESS inverter can charge/discharge a max of 3.6KW at a given instance (7.2KW system total since they behave as a single unit).  Having 2 x 2.4 KWH batteries on each inverter means that will do so for longer.  What point am I missing?

The end objective of getting the Squirrel Pods was to eventually flip over to Octopus and use their off peak deals, but to do that at the moment would be not be financially beneficial. 

With Pylontechs, you get a max of 1.2kw per battery so you need 3 batteries on each inverter to get the max 3.6kw. Hence, 2 batteries would give a max of 2.4kw per inverter.
If you have Uhome batteries, this might be different ??