SolaX X1 G4 Hybrid inverter + AGM batteries

[benlloydking]

Hello,
I have a SolaX X1 G4 3.7kW Hybrid inverter and 5.1kWp of Solar cells. I am saving up for a triple power battery but in the mean time I have access to a large number of free 12v Yuasa REC36 AGM batteries from a school project I run (Greenpower Racing). They will have done 20-30 cycles.
The X1 inverter manual states that the battery voltage should be between 80 and 480v peak and that "X1-Hybrid G4 series inverter charge and discharge system can be equipped with high voltage lithium battery and lead acid battery." I have enough batteries available to build a 9s3p configuration which would be a nominal 108v and 11.6kWh capacity. I understand that the actual capacity will be lower, perhaps half this amount, but still enough to be useful. I also understand that AGM batteries do not normally require a BMS as they will self equalise. The x1 hybrid manual states how to set min and max SOC, but not how to set the type of battery or the nominal battery voltage.
How would the inverter know what 100% SOC is? Should I be able to set what voltage 100% SOC corresponds to or is it just that it infers this from the batteries limiting current as they reach peak capacity? How do I prevent the inverter from trying to charge at an excessive voltage? Would a BMS be needed for this system? If so which BMS would work?
Inverter manual: https://www.solaxpower.com/wp-content/uploads/2021/02/X1-Hybrid-G4-User-Manual-614.00495.00.pdf
Any thoughts and responses are gratefully recieved.
Thanks,
Ben

 

[benlloydking]

Update: I have found that on an older Gen 2 SolaX inverter the settings I require are available - an option to set charge and discharge cut off voltages, but as yet I've been unable to find the settings on the G4 model. If anyone out there has any insights as to how to access these settings I would be very grateful.
Thank you,
Ben

 

[slizovskiy]

Hi Ben, Is your Solax inverter doing ok with overpaneling? I have 4.8 kW solar panels and also want to buy a used 3.7 kW Solax Hybrid. It says in the DataSheet that that 4.0 kW is the recommended Max for panels.

 

[DannyC93]

Hello Ben,

TLDR. Even with G3 inverter Solax can guarantee it with support lead acid and the customer support is horrendous as the 'specalists' I've spoken to seemed to have difficulty with what lead acid was thinking it was a brand of battery not a type.

If you want lead acid sell your Solax gear and buy from Victron or another similar company never Solax unless you doing lithium then it works great but after my experience as an installer never touching their gear again dropped all my stock of thiers on eBay and cut ties.


So let's begin.

I've had the similar issues and had a months of calls, back and forth with my local distributor. About how they were selling the newer G4 inverters claiming lead acid support, when that isn't the case they only support lithium battery types. The older G3 variants do work with lead acid(as reported by Solax ) but this wasn't exactly true in my case.

I've had several warranty returns on a X1 retroFit G3 3.7KW (I've been sent 3 inverters each one bar the last wasn't a retrofit or a G3 variant so didn't have the settings), I been installing these inverters now for a customer, over the past 15 months each time Solax says they will work with lead acid but until this last one none had the settings

Even on the final inverter a G3 variant the settings fail to hold after setting the correct values for the battery bank size (eg absorption, float, cutoff) and defaults to a factory voltage.

This time it's close to the right values and better then a first model I have that defaulted to 400V for charging their HV lithium bank and nearly boiled the lead acid bank, But still is over discharging and under charging the bank by a value which is slightly off that I can't even size the bank correctly to compensate without finding several high AH 3v cells. Also I've still concerned about having the lead acid voltages they want of Min 70Vdc and Max 300Vdc on a lead acid bank in a domestic setting, it took a while to find a decent solution for a safe enclosure for off gassing, fire prevention and DC electric shock etc. Don't know why 48V wasn't enough for them and seems like it would have a much higher cost for variable higher voltage DC charger in the inverter. But hey I'm and installer not an electrical engineer per say.

I've installed many of their inverters (solar, hybrid) in the past years ago but not a retrofit and never had a problem but since launch of G4 and discontinuation of the G3 all their knowledge of older products (and in general) has disappeared from their company and support staff, I've had several calls where I have had to explain what a lead acid battery is and that it isn't a brand of battery but a type.

If anyone knows why or how I can fix the settings not holding in a retroFit, I would be grateful as I don't want to leave the customer (family member, so not too bad but still) with this issue long term, we are looking at a completely different installation but have several other Solax product working perfectly (and already in their monitoring ecosystem) and don't want to mess with a setup that's somewhat working and it would be costly to change everything at once, they are not in the best financial place (neither am I to cover their cost) to go ahead with that.

Business wise, I've cut ties with Solax and won't recommend or install their products again even if customer supplies or want them I will decline the work and explain the issue I've had with them and their products and more so their customer support and warranty service. It's taken months and month of fighting them to get a replacement each time when it's either wrong or faulty and they promise the one they send will work and does support the features that are needed for my installation. Also their answer to everything is to send you the same manual over and over again even when you say this is the wrong manual, or it doesn't say that the iverter supports lead acid.
On I found funny was a G4 5KW Fit manual, I received in one of these many returns did said it supported lead acid, but didn't (nothing in settings menu) and they said it didn't and I didn't say I needed lead acid but I sent them several emails and pictures of the manual and prior email chains (of which I have many) clearly stating it does support lead acid and that is the only feature I required of them when in fact the inverter didn't.

Sorry once I started typing I went off on one a bit with this rant do I've included a TLDR.

 

[benlloydking]

Hello Danny, sorry to hear of your troubles with SolaX. I decided to ditch the lead acid idea and saved up for a Lithium triple power master and slave unit. These have been working perfectly and so far I am very pleased with them.
Best of luck, Ben

 

[DannyC93]

Hello Danny, sorry to hear of your troubles with SolaX. I decided to ditch the lead acid idea and saved up for a Lithium triple power master and slave unit. These have been working perfectly and so far I am very pleased with them.
Best of luck, Ben

Hi Ben, that's fair enough then. I wouldn't have done that myself personally or recommend that to my customers, as the customer service and warranty process s**t show they have in the off chance it develops a problem in the future, was enough to steer me far away from the company for future installs.

Update on the install, I was able to retrieve the installed firmware and crack it with the intention of modifying the factory default to more usable settings and then re-flashing it. But I stumbled upon a setting tree and the super password to access it. Turned out even though they said they sent it to me as a one off build that guarantees lead acid support, it wasn't it was a old model with updated firmware but the abilities were disabled in the firmware by default. I was able to use the super password and enable to old firmware and for the settings working and so far they seem to hold.

Not sure of the legality of distribution of the super code so I won't say it but if anyone need more information I can try and help not active on here very much but will check back now and then.

Regards,
Dan

 

[jeepman]

hello dannyc93，
I had the same problem as you, solax sent me new firmware that can support lead acid batteries, but I didn't have time to upgrade.
Also, I saw this video on youtube that might help.

 

[Farmwi]

Please excuse waking a sleeping thread.
I'm looking for a high voltage mppt charger to fill a custom Lion battery pack to user specified voltages.
Goal 320vdc and or 170vdc.
Any experiences with custom Lion?