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EG4 Chargeverter Battery/Inverter Communications

Note that it'll take a few minutes to start ramping up and will ramp up very slowly, so you may not think it's doing anything...
Thanks. I clearly don't understand this thing yet. I didn't think it was doing anything at all. I have my temp cord from the gen into the inlet box hooked up with just 12 awg wire (what I had laying around) so can't let it get that many amps (had it set to just 10 to test). This is out at a new building we're doing at a nearby property. I shut down the gen and went home after making that post but will test it again in the morning. Appreciate the input / correction.
 
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Thanks. I clearly don't understand this thing yet. I didn't think it was doing anything at all. I have my temp cord from the gen into the inlet box hooked up with just 12 awg wire (what I had laying around) so can't let it get that many amps (had it set to just 10 to test). This is out at a new building we're doing at a nearby property. I shut down the gen and went home after making that post but will test it again in the morning. Appreciate the input / correction.
Note that you’ll have to do some nonstandard wiring to make a 120V input work
 
OK, got it hooked up (240V ‘cause that’s much easier than special wiring). Set it at 54V, 50 amps because that’s about 75% of what the little Champion generator on site is rated for. Worked great and very little fan noise (less than the inverters). Put it up to 60 A for a few minutes and that started to get a bit louder. Backed it off to 50A so as to not tax the generator. Will buy another and run both off the 10K gen. Will likely set both to 50A so as to keep things quieter and not tax that larger gen. Overall I’m happy but would be much more impressed if EG4 could figure out how to have inverter communicate with it (or the batteries with it and the inverter). As it is it’s like having about 50% of the info you desire at any given time. But still better than buying one large inverter gen.
 
Overall I’m happy but would be much more impressed if EG4 could figure out how to have inverter communicate with it (or the batteries with it and the inverter)
Yeah, there's an obvious missing integration between all their pieces. The engineers put the interfaces in, but they farmed their firmware out to Elbonia, and the everything-working-together-seamlessly function is just plain missing.

Good to hear you got it running!
 
Communication with the "Master" battery and Inverter can be done with software. The only value BMS communications provides that the CVGC appears to use is SOC.

120 VAC and 240 VAC both work.

The 120VAC pigtail:

20240731_171551.jpg
 
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Communication with the "Master" battery and Inverter can be done with software. The only value BMS communications provides that the CVGC appears to use is SOC.

120 VAC and 240 VAC both work.

The 120VAC pigtail:

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I built a custom cable from my EU3000i to my ChargeVerterGC:


Screenshot 2024-07-31 at 5.35.12 PM.png

Just make sure you label it as ChargeVerter ONLY, someone else who doesn't know trying to use this on some other 240V appliance will not have a good experience.
 
Finally completed (mostly) my ChargeVerter controller. I have both the new CV-GC and the older CV-Yellow. The two relays are 12vdc coils with double pole double throw contacts. The HVAC/Bell transformer is wired for 120vac input routed through one NO contact on a relay and a 5 amp fuse. 12vdc power via a fuse is routed via an NO contact on one of the relays to two connector that can be wired to 12vdc audible and/or visual indicators. The relays are energized by a manual switch or via a cable plugged into the RJ45 jack for external/remote control. I can use the dry contacts on the CV-GC, Inverter or any of the SunGoldPower batteries or by software to control both chargeverters. Once the relays are energized the HVAC/Bell transformer is powered providing the 23vac to the contactor (closes the contactor) and the 12vdc power is available on two connectors for signaling. The 12vdc power comes from a 20-90vdc to 12vdc converter (10 amp) connected via a fuse to my battery bank. This 12vdc also powers an HDMI 10 inch touch screen connected to the Solar Assistant PI and also powers the PI via a 12vdc to 5vdc converter

InsideView.jpg

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LeftView.jpg

RightView.jpg
 
The "new" EG4 Charge-Inverter manual shows that the RJ45 (RS485 bus) uses pins 1&2. EG4 typically uses pins 1&2 on their RJ45/RS485 ports for comms to other devices such as an Inverter, Solar Assistant or the BMS_Test software (only one at a time).

Specifically for the LifePower4 batteries pins 7&8 are used for battery to battery comms and pins 1&2 are used for Inverter comms.

If using an EG4 Communications Hub pins 1&2 are no longer connected to the inverter so I would suspect that connecting the ChargeInverter would not be an issue, much like using an external separate charger.

The manual might be assuming with BMS to Inverter comms that pins 1&2 are in use, you cannot have more than one "Master" on an RS485 bus.
I suspect that in the absence of comms the ChargeInverter uses the Max Charge Voltage and Max Charge Current you program in and with comms the ChargeInverter uses data it gets from the battery and overrides the Max Charge Voltage and Max Charge Current you program in.

I have not yet purchased the new ChargeInverter but will in the near future so I can break down the communications.
Like your thoughts, as I just installed the EG4 Chargeverter, and using the SA, I have the Growatt connected to the SA and the BMS battery Master connected to the SA.. I was hopeful that I would be able to get the Chargeverter to Comm to the Growatt, however with the Growatt Set to US2 in program 5, meaning Lithium Batteries, no BMS comm. I tried changing Program 05 in the Growatt to L1 but since its not connect via BMS from Batteries, Growatt just goest to Fault 20 .. I would really like to have the Chargeverter be seen by the Solar Assist,, as it stands for now. All SA sees is Amperage going in , and has no idea there is a Grid Feed via the Chargeverter. I am hoping someone finds and figures out a way SA Data can reconize a Grid input in this case the EG4 CV.
 
I have been looking at the CV-GC communications. It will only communicate to my LifePower4 if it is set to address 0 (Master). The CV-GC will not talk to any of the other batteries. In addition the CV-GC is using an undocumented modbus command that only the "Master" will respond to. I have sent this same modbus command to the other batteries and they do not respond. I also tried a number of ways to see if I could read any of the settings in the CV-GC and I could not. I was hoping I would also be able to set the values via software.
I created a test software which has the CV-GC thinking it is communicating with the "Master" BMS. I can modify data such as voltage and SOC being reported by the BMS. The voltage on the display will show BMS reported voltage if there is BMS communications otherwise it displays voltage as measured at the CV-GC output. Current as displayed is the output current and not a current being reported by the BMS. The only parameter the CV-GC responds to from BMS communications is SOC.

Since I can control the AC power to both my ChargeVerters with software I am not concerned than the CV-GC has no BMS communications.

I also determined that both the CV-GC and Solar Assistant can "share" the same LifePower4 RS485 bus. I used an RJ45 splitter and both SA and the CV-GC had no issues, I suspect it is because of the different communication protocols used by both.
 
I have been looking at the CV-GC communications. It will only communicate to my LifePower4 if it is set to address 0 (Master). The CV-GC will not talk to any of the other batteries. In addition the CV-GC is using an undocumented modbus command that only the "Master" will respond to. I have sent this same modbus command to the other batteries and they do not respond. I also tried a number of ways to see if I could read any of the settings in the CV-GC and I could not. I was hoping I would also be able to set the values via software.
I created a test software which has the CV-GC thinking it is communicating with the "Master" BMS. I can modify data such as voltage and SOC being reported by the BMS. The voltage on the display will show BMS reported voltage if there is BMS communications otherwise it displays voltage as measured at the CV-GC output. Current as displayed is the output current and not a current being reported by the BMS. The only parameter the CV-GC responds to from BMS communications is SOC.

Since I can control the AC power to both my ChargeVerters with software I am not concerned than the CV-GC has no BMS communications.

I also determined that both the CV-GC and Solar Assistant can "share" the same LifePower4 RS485 bus. I used an RJ45 splitter and both SA and the CV-GC had no issues, I suspect it is because of the different communication protocols used by both.
Marionw - hi, if I understand you correctly, say you have a rj45/rs485 from master bat bms to SA, you put in between a rj45 splitter, Bat BMS to single side port of splitter, and from there ran rj45 to SA which has usb-A on other end to the SA, and Rj45 from splitter to rj45 to the CV. Am I understanding corrrectly, and it works? SA showing the batteries and CV is seeing SOC.
Here is what I am wanting to figure out. How can I get SA to see CV as Grid Charging. As it is now for me. My Growatt is connected to the SA and no BMS to the Growatt and my bat master BMS is connected to my SA.. but since my Gen is connected to the CV, SA does not see as Grid , only that the batteries are getting a increase in Amps charge, but it has no ideas from who. As far as the SA is concerned it could be from Mars. lol Any ideas ?
 
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Marionw - hi, if I understand you correctly, say you have a rj45/rs485 from master bat bms to SA, you put in between a rj45 splitter, Bat BMS to single side port of splitter, and from there ran rj45 to SA which has usb-A on other end to the SA, and Rj45 from splitter to rj45 to the CV. Am I understanding corrrectly, and it works? SA showing the batteries and CV is seeing SOC.
Here is what I am wanting to figure out. How can I get SA to see CV as Grid Charging. As it is now for me. My Growatt is connected to the SA and no BMS to the Growatt and my bat master BMS is connected to my SA.. but since my Gen is connected to the CV, SA does not see as Grid , only that the batteries are getting a increase in Amps charge, but it has no ideas from who. As far as the SA is concerned it could be from Mars. lol Any ideas ?
Currently SA will never see the CV-GC as there is no "Slave" response that I can find, that is the CV-GC cannot/will not respond to commands from a "Master".
I use USB to RS485 converters (see below). Since I use an EG4 Communications Hub, the bottom battery in my stack has an unused RJ45 jack in which I plug in the splitter. The cat5 cable from the CV-GC plugs into the splitter and a cat5 cable with an RJ45 connector on one end plugged into the splitter and bare/open wires on the other to which I connect the orange/white and orange to the USB to RS485 converter which then plugs into SA. I know of no way for SA to monitor the CV-GC (unless EG4 releases some undocumented communications), however since SA is showing each battery, SA will also display charge/discharge current.
Of course custom software could be used to do what you want. If you had software that polled the batteries (software connected to the splitter and SA connected to the software) then the software could modify the "Version" data that is displayed at the top of each battery to indicate CV-GC status rather that the battery firmware version.

See/Review:




RJ45_Splitter.jpg

USB_To_RS485.png
 
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I just connect my ChargeVerters to the batteries using the Degson connectors. The built-in bus-bars are good for 600A, and the parallel cables are good for 250 (or is it only 200?) amps, so another hundred amps at the ends of the middle somewhere isn't going to unbalance the SOC.
I ordered the Degson connectors from Signature Solar. Even called them to conform this will work. Well, today I opened the ChargeVerter V2 boc and the cable that connects to the ChargeVerter is a lot thinner than the cable used for the Degson connectors to the battery. Looks like only option is the bus bars.
 

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I ordered the Degson connectors from Signature Solar. Even called them to conform this will work. Well, today I opened the ChargeVerter V2 boc and the cable that connects to the ChargeVerter is a lot thinner than the cable used for the Degson connectors to the battery. Looks like only option is the bus bars.
With that male Degson you got a female Degson with a M8-1.25 female thread, bolt that (use a 1/4-20 bolt and nut if you don't have the M8-1.25 bolt) to the ring terminal and use a set of DC Battery parallel cables.

Screenshot 2024-08-26 at 9.37.18 AM.png
I'm working on a 3D-printed box, but the heat-shrink works OK as long as there's no movement that could cause abrasion.
 
With that male Degson you got a female Degson with a M8-1.25 female thread, bolt that (use a 1/4-20 bolt and nut if you don't have the M8-1.25 bolt) to the ring terminal and use a set of DC Battery parallel cables.

View attachment 239325
I'm working on a 3D-printed box, but the heat-shrink works OK as long as there's no movement that could cause abrasion.
FWIW: https://www.thingiverse.com/thing:6746406

Working on a 4-way bus-box, and other bushings for cables like the above.
 
Here is what I am wanting to figure out. How can I get SA to see CV as Grid Charging. As it is now for me. My Growatt is connected to the SA and no BMS to the Growatt and my bat master BMS is connected to my SA.. but since my Gen is connected to the CV, SA does not see as Grid , only that the batteries are getting a increase in Amps charge, but it has no ideas from who. As far as the SA is concerned it could be from Mars. lol Any ideas ?
I'm pretty sure there are many users which would love to see this feature in SA (me too). Have you ever tried to request such a feature via SolarAssistant support?
I think, it's even not really required for SA to support the EG4 Chargeverter protocol itself, it may be enough to read values from an external shunt and treat these current like an additional "grid based battery charging". SA is already able to talk with Victron SmartShunt, so it would not be a big deal for SA to implement such a feature.
 
I think, it's even not really required for SA to support the EG4 Chargeverter protocol itself
That's good, because there's no 'CV Protocol', the CV talks RS485 to the batteries directly as a modbus master, so while you might kludge up a modus listener, that's unlikely to be a SA feature.
, it may be enough to read values from an external shunt and treat these current like an additional "grid based battery charging". SA is already able to talk with Victron SmartShunt, so it would not be a big deal for SA to implement such a feature.
That's more likely, though it's a pretty edge case, so not sure how to convince the SA folks to add it in. Don't get me wrong, I'd love to have the CV contribution to charging somewhere in there, I'm hoping it'll be a small number, and I can just as easily get it from measuring the CV AC Input power.
 
Hopefully EG4 will expand the CV-GC firmware to where the CV-GC charging parameters (Voltage and current) as well as the Generator (dry contacts) setpoints can be modified by software.

Currently the CV-GC only recognizes SOC when there is BMS communications and EG4 uses an undocumented command/function to facilitate this.

It will be a game changer once EG4 opens the communication to the CV-GC and allows total remote/software control
 
If the CV is charging the batteries based on voltage it may do something different, so you'll probably want to keep the CV voltage at 55.0V or something so as not to overcharge the batteries. I keep mine at 52V, which is sufficient to prop up the SOC to about 25% even though the CVs read 0.2 volts apart, and contribute different currents to the battery bank. I'm away for hurricane season now, so I can't make any changes, but when I get back I'll probably set the CV voltages to 55.0V and use the Gen Dry Contacts to enable the relays that power the CV AC inputs. Then I can set the 'generator' to come on at 20% and 'stop' at 40% or something. I'm working on a better control algorithm that'll probably run on the Raspberry Pi that's inside the primary inverter, so I can control charging based on weather (fully charge before hurricanes arrive, don't use grid power to charge the batteries if it's only a short time till sunrise, etc. But that's an optimization for later...

Reviving this post as I'm doing a lot more charging as winter is ramping up. I've heard it wise to charge to 100% from time to time to force cell balancing, is this true on the BMS for the EG4 Wall Mount batteries? A recent video from Will Prouse mentioned this very thing (link below). Given that I've been leaving my voltage setting on the CV at 56.2 volts and typically charging to 80 or 90% SOC as reported on the 18k and manually stopping the generator. Every once in a while I let the generator charge to 100% and stop once I see the CV current come down on it's own as the batteries go into "Stanby" mode. This leaves me with some questions to get wisdom from the masses on, especially in regards to "overcharging":

1) What exactly did you mean by overcharging @wpns, and am I doing that when charging to 100% at 56.2v @ 100 amps and letting the EG4 Wall Mount batteries charge until the BMS forces "Standby" mode? What issues might this cause?

2) For a long winter with little solar, what is an optimal charging percentage cycle for daily charging to avoid unnecessary degradation? We are using 25-30% daily of the power our battery array stores.

Video from Will:
 
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Circling back on this - any update from @EG4TechSolutionsTeam on CV communications with batteries? The manual claims that the CV will talk to EG4 batteries over RS485, but there is no documentation of how to make this work.
 
The Chargeverter communicates with the EG4 LifePower4 V1 batteries on the pins 1&2 RS485 bus. This bus is also used for closed loop communications to an EG4 Inverter or Solar Assistant. This bus uses the not well documented "Narada/EG4" communications protocol. This is why the Chargeverter manual states that you cannot use "closed loop" and the Chargeverter connected to the batteries. In addition Solar Assistant uses the same pins 1&2 RS485 bus so you are limited one of the three at any time. If you install an EG4 Communications Hub, it provides the closed loop communications to the inverter thus freeing up the pins 1&2 RS485 bus on the batteries for either Solar Assistant or the Chargeverter
 
SA seems to work using either pins 1&2 or 7&8 as best I can tell... (with Lifepower4 V1 batteries)
 
Circling back on this - any update from @EG4TechSolutionsTeam on CV communications with batteries? The manual claims that the CV will talk to EG4 batteries over RS485, but there is no documentation of how to make this work.
From my understanding, it is for only to benefit the dry contacts side of getting your Generator online to charge batteries.. If your not needing that . Having the CV talking to your batteries has no value to be used..
 
From my understanding, it is for only to benefit the dry contacts side of getting your Generator online to charge batteries.. If your not needing that . Having the CV talking to your batteries has no value to be used..

If you have SOC, can't you use that to turn charging on and off instead of using voltage? Or am I misunderstanding and all the "ON" and "OFF" things do (either voltage or SOC) is control when the dry contacts are open or closed...
 
My understanding it the only purpose of the CV to rs485 Com to batteries is for the SOC and setting to use the Dry Contacts to excite your Generator for Charging which the CV is connected with.. That is all I know or understand and have been told. I may be wrong. But my own experience , that is what I have seen with my CV EG4 charcoal model..
 

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