Fox ESS H1-5.0-E ~33KW Peugeot E208

[usus]

Hi, what isolated can bus are you using?

[Kevin]

Hi

This is the one I am using

https://thepihut.com/products/2-channel ... spberry-pi

Even thou says raspberry pi, it has a connector for Arduino , or any processor with SPI

[art103]

Hi,
New to the forum, but have been building a V2X adapter for my Nissan Leaf (ChaDeMo).
Thank you for the great information (spreadsheet, photos, CAN logs, BYD-Battery-Emulator-For-Gen24, etc.)

I'm using the FoxESS AC1-5.0-E as the inverter and have everything hooked up and working including dynamic import and export via an emulated RS485 power meter.
However, I was concerned about inrush current and came across this comment:

Regarding precharge contactors, FoxESS have them built in to the inverter so you don’t need it. The main contactor will close when full and valid can information is sent.

Are you sure?
I measure the capacitance of the inverter as around 10uF (6uF to be precise) when in the "Waiting..." state based on time taken to pre-charge with a high impedance source.
This would also make sense given the 40 Ohm precharge circuit (and contactors) in the FoxESS BMS.

Personally I am going to add a pre-charge resistor and contactor, as I want to prolong the life of my inverter and vehicle contactor - especially as it will be started and stopped daily when the car is in use, but would value any feedback / discussion.

[usus]

Hi, art103
I am preachargin every time the inverter.
What do you mean by? "emulated RS485 power meter" how is working?

[art103]

Good to know, thanks.

The FoxESS inverters support an Eastron SDM230 Modbus energy meter instead of the supplied CT clamp. This is connected on pins 1&2 of the "Meter/CT/RS485" connector.

As long as you can measure and update the reported power at a rate of ~100ms, you can emulate the grid power. The inverter will try and adjust its output to make the net power zero, so by applying an offset to the measured value, you can get the inverter to output anywhere between +/- max power.
The Inverter only reads the frequency (once at startup) and the Active power registers, so is very simple to implement.

For my solar setup (FoxESS H1-3.7-E), this lets me control import / export. E.g. to take advantage of cheap charging rates, or high reward export rates with grid demand response / saving sessions in the UK.
This uses an ESP8266 for the MQTT control part and an EFM32 micro controller to measure and select between 2 CT clamps: one on the grid connection and one on the inverter connection.
During normal operation, I use the grid CT. When commanding an emulated offset, I use the inverter CT.

For the V2X application, I already need to accurately report battery current to the ChaDeMo CAN interface. By offsetting this and reporting to the inverter via RS485, I can control the charge / discharge current.

[woleg]

For the V2X application, I already need to accurately report battery current to the ChaDeMo CAN interface. By offsetting this and reporting to the inverter via RS485, I can control the charge / discharge current.

I have a copy of the official CHAdeMO spec and built my own library based on it. Dala’s version has quite a few errors which can be expected when reverse engineering so be careful.

https://crates.io/crates/chademo-rs

Tested on my own V2H setup using a Nissan Leaf.


As for the FoxESS inrush. Can you measure it using a scope please? I’m kinda curious.

[art103]

Thanks for the link.
I've also implemented from the spec and written the state machine from scratch. The only bits missing were the V2X CAN message details, but the combination of various open projects allowed me to fill in the blanks to get it working reliably.
Once I'm happy with the safety side (Short Circuit, Isolation and Insulation testing) I'll upload to Github.

I'm currently waiting for a contactor and 40R 50W resistor. Once I've got them installed I'll try and get some scope measurements from the current sensor at connection time.

[woleg]

There’s no need to simulate a power meter, you can drive a FoxESS manually by commanding power.

I’ll edit this comment with a link to their internal communications specification document.

Here:

Look up Active Power Configuration.

[art103]

Wow, thank you.
I implemented the power meter simulation after scouring the forums for exactly that sort of document and not finding it!
I can feel a re-configuration of my home automation coming on

[art103]

Ok, I thought that would be via the "Meter/CT/RS485" connector, pins 3&4.
The protocol does not match up at all with the following:
https://github.com/StealthChesnut/HA-Fo ... -Addresses

How / where can I access the RS485 port for the document you shared, please?

Also, the active power configuration only lets you specify a maximum export, it does not let you control the import (charge) or export (discharge) power directly like I can via the meter emulation.

[woleg]

Modbus control is done on pins 3 & 4 (Modbus Meter is 1 & 2)

There's a discussion here for driving the inverter manually. https://github.com/nathanmarlor/foxess_ ... ssions/513

[EdvartsW4E]

Amazing tread and a cool project!
Do you maybe have a CATL6s2p datasheet to share?

[usus]

Hi. I was looking for a while and haven't found. From testing 3.3 to 4.15 is around 85% capacity. I tried lower to 3 V but I have a weak cell in one pack and after 3.3 is dropping to fast generating 250mV dV so I do stop testing.

Hope that is helpful.