My experience with GroWatt SPF 3000 TL LVM ES and Signature Solar's EG4

[mtts]

Placeholder:

Because I already had the browser crash once on the forum, this is a placeholder I will update in a minute from a laptop.

Here are the two related posts: https://diysolarforum.com/threads/growatt-firmware-update.36076/post-500680

and

Limited charging current after adding EG4 LL battery

Another Data point: I have a single LifePower4 48V100A from Signature Solar attached to a Growatt SPF-3000TL LVM-ES inverter. The programming is set to LI and I see the charge current (overall and utility) are both 12A (which cannot be changed when LI battery is configured). Is the BMS forcing...

diysolarforum.com

 

[mtts]

Good experiences with Ian of Watts247. Year later tried to add an EG4 and could not get it to work until I updated the GroWatt communication board firmware. See the above link.

@RichardfromEG4

1. There's no useful manual w the EG4, either printed or PDF. Absolutely nothing about needing to run a minimum firmware on the GroWatt. And v51.01 from a brand new unit shipped 4/2021, fresh off the boat, is not new enough. It flat out will not work until the GroWatt is updated. [You can use USE2 temporarily, but SOC will be in 25% increments: no granular tracking or insight].

2. The terminal bolts provided with my EG4 were too short. For customers stuck in that situation, right now, they are the same style, as common body fasteners for Toyota, etc, which are longer and work. I don't know what the max length is into the threaded connection, but the provided screws with my EG4, were at least 2-3mm too short to be torqued properly with the provided cables, and had to be 5-6mm longer for the stuff I use. I use some really thick ~3mm crimps, and it's not possible to get the supplied terminal screws started. I would have easily striped hole or bolt, unless I used the tiny Signature Solar cables, and even then, the bolts were not long enough. Your chinese manufacturer is skimping on fasteners.

2. Not even a piece of paper, that says how the DIP settings need to look when facing from the front, when it's the sole master battery, or setup w 2 x EG4's. The videos on YouTube, don't work because they don't mention the firmware issue. [Master needs to be in the all down position]

if i think of anything to add, i will.

 

[mtts]

IAN HELPED. A LOT.

and as he said, 'I don't even sell the d__m things.' ?

 

[mtts]

Followup: I let the the system drain, in a organic way, discharging the EG4 battery low. I was curious to see what would happen.

At around 5AM, and at exactly 5% charge [Batt Type LI/01, ethernet/RS485 comms cable plugged-in and working as normal], with no incoming solar [yet], the GroWatt inverter turned off. So everything that was on AC power, turned off. Including the fridge/freezer. The GroWatt was still basically on, with Error 4 [low battery].

I realized, as the sun came up, and the GroWatt started charging the EG4....

@RichardfromEG4 WHY did you name the recently-released MPP LV6548-style inverter all-in-one, the SAME as the battery? Same logo and everything? If it's a SS exclusive product, come up with a unique name.

...that as the charge level crept, to 6%+, the Error 4 was not clearing by itself, and so the inverter remained off. There didn't appear to be any setting in the GroWatt to set the 'ON' point percentage of the battery. I reasoned, the ON-point would be some threshold determined by the EG4 BMS. [No useful documentation. See prior posts].

The sun came up, 50 watts.. 100 watts... 150 watts. I threw on the generator to speed things up and to instantly bring back AC power.... then, remembering the idiocy documented below, I immediately shut it off before the GroWatt had an opportunity to switch to Grid/Generator:

@RichardfromEG4 WHY does the BMS tell the GroWatt what the Maximum >AC< Charging Input [Setting #11, the amount of power, in battery-charging amps, to use from Utility/Grid/Generator] should be? The EG4 BMS has no business dictating that. Yes - it can - for the TOTAL charge input, Setting #2, which in turn, limits Setting #11. Which means, that if ONLY setting #2 is set by the EG4, the battery will never receive more amps than the BMS wants. Someone with extremely limited practical understanding [my first thought was joe the janitor, although senior janitors tend to have more common sense than everyone else], programmed the BMS to vary the maximum AC input, when this should ONLY be set by the User/System Installer who knows what their Grid/Generator connection is capable of. Very few - none, if any - mobile off-grid set-ups are going to have the suggested 10kw generator [for AC Input], in the GroWatt manual, that some air-head must have assumed was reality, and thus told the EG4 Battery BMS it should set automatically. Setting it from the BMS programatically, equates to the User being locked-out, of setting it through the front panel. And, the User can only temporarily reduce #11, through a convoluted use of the GroWatt Shinephone App and supplied WIFI Datalogger, to set it to something more reasonable [like 10 or 15 amps for a 3kw generator. 10amps @ ~52v, equating to roughly 520w output from the Generator, being a typical idle-production of a 3kw inverter-generator].

The non-solution 'solution' to that, is for the user - your customer - to use USE2 battery setting in the GroWatt. Then you lose all percentage and other useful BMS reporting.

Otherwise, with the LI/01 setting, when at any level of discharge below 90%, the EG4 will use the BMS comms cable to tell the GroWatt that setting #2 is to be 50 amps, and that setting #11 - something it should not touch! - is 40amps [2080 watts]! Somewhere above 90%, the EG4 tells the GroWatt that setting #2 should now be 12 amps, and that setting #11 should be 12 amps [or maybe #11 is reduced by the GroWatt when #2 is restricted]. I have manually set #11 through the app, to 10 amps, run the generator and observed the correct 10a@52v being put into the battery [minus around 0.68 amps, the self-consumption of the GroWatt]. Then, on a later cycle when the battery discharged below 90%, I have witnessed the EG4 BMS change #11 back to 40 amps! Nothing was restarted in that time period, and I have seen it more than once. So for sure, the EG4 BMS is presently telling the GroWatt what #11 should be, effectively locking that setting out from the front panel.

However, the above is as I understand, only from my limited perspective & observation.

I manually set #11 to 10amps, again, and started the generator. When the combined solar charging and grid charging brought the EG4 Battery level to 15%, the Error 4 cleared, and the AC Power/Inverter turned back on.

 

[Solar Guy Richard]

@RichardfromEG4 WHY did you name the recently-released MPP LV6548-style inverter all-in-one, the SAME as the battery? Same logo and everything? If it's a SS exclusive product, come up with a unique name.

It doesn't have the same name. We have the EG4-LL or EG4-LifePower4 batteries (voltage and AH vary), and the inverter line is the EG4 6500EX-48. They are both EG4 brand, and EG4 is a separate company from Signature Solar. Although both were originally started by the same ownership, they have evolved into 2 separate (but related) companies. Signature Solar is a solar wholesaler and distribution company. EG4 is a manufacturing and development company. EG4 is currently working to expand it's offerings to a few other distributors that have no affiliation with Signature Solar.

@RichardfromEG4 WHY does the BMS tell the GroWatt what the Maximum >AC< Charging Input [Setting #11, the amount of power, in battery-charging amps, to use from Utility/Grid/Generator] should be? The EG4 BMS has no business dictating that.

This is a complicated question to answer but I'll do my best. The BMS is solely designed to protect the battery - and it is designed to adjust charging current based on current state of charge in order to accomplish this. As it nears 100%, it wants to reduce the charging current to ensure it gets as close to 100% without going over. Growatt has designed their system to allow the inverter to dictate setting #2 to accomplish this - the total charging current is dictated by input from the BMS. Growatt also programmed the inverter so that the setting you refer to (Setting 11) is tied to setting #2 directly - instead of a logic based option. Although Signature Solar has a great relationship with Growatt, the do not control the engineering team. It is not a choice of EG4 to control setting 11 through the BMS - it is the choice of the Growatt to allow setting 11 be controlled by the BMS. Although I personally believe its a good thing it is programmed this way, I wouldn't have a say in it either way because that programming is 100% determined by Growatt.

 

[mtts]

Ok. That clarifies a lot. I appreciate it.

 

[RonP]

I've been enjoying figuring out the nuances of the SPF 3000TL LVM-ES and the EG4-LL batteries working together. The documentation definitely needs a lot of work. Maybe this group can create something together? I know that I've gathered a lot of good ideas from these forums and the various Youtube videos. I'm probably going to have to write my own operational procedures for the various situations I am trying to anticipate. I was playing with charging the batteries using my portable generators instead of solar last night and learned some interesting lessons that I needed to know before I did it during an actual outage.