Feature Request: Loadbalancing use-case

[vdweegen]

Hi all,

First of all, I've been using the SmartEVSE with Serkri for a while now, and I've been extremely happy. Fantastic work!

I'm looking for some help w.r.t. a specific load-balancing use-case, as I've recently decided to upgrade my setup by replacing my old 1-Phase "dumb EVSE" with another SmartEVSE unit.

So, currently i've got two SmartEVSE's, both running Serkri 1.8.0.

Both SmartEVSE's are connected via modbus, to each other, to a Sensorbox, and to two kWh meters (Eastron SDM72D-m).

LoadBalancing is configured, SmartEVSE 1 is Master, SmartEVSE 2 is configured as Node-1 (Slave).

SmartEVSE 1 has a fixed 16A, 3-Phase cable which is controlled by Relay 1, SmartEVSE 2 has a fixed 16A, 1-Phase cable which is controlled by Relay 2 (L1).

While loadbalancing is working correctly by making sure the ChargeCurrent on both units together is not greater than CIRCUIT, I was hoping if would be possible to have the Slave Unit have its own kWh-meter configured. I've noticed that when SmartEVSE2 is configured as Node1 (Slave), it is not actually using the configured kWh-meter (The configured kWh-meter values are also not used to display or even updated in the ev-meter->current fields for the slave-unit).

My setup is as follows.

                   mains
                     |
              [main breaker 3x25A]
                     |
              [kWh meter SENSORBOX]
                     |
  -----------------------------------
  |            |                    |
                          [smartevse breaker 3x16A]
                                    |
                              ----------------
                              |              |
                        [kWh meter 1]  [kWh meter 2]
                              |              |
                        [relay 1]         [relay 2]
                              |              |
                         [car 1]           [car 2]

Configurations are:
// SmartEVSE1
{ "version": "SERKRI-1.8.0", "mode": "SMART", "mode_id": 3, "car_connected": false, "wifi": { "status": "WL_CONNECTED", "ssid": "-", "rssi": -62, "bssid": "-" }, "evse": { "temp": 25, "temp_max": 65, "connected": false, "access": true, "mode": 1, "loadbl": 1, "pwm": 1024, "solar_stop_timer": 0, "state": "Ready to Charge", "state_id": 0, "error": "None", "error_id": 0, "rfid": "Not Installed" }, "settings": { "charge_current": 86, "override_current": 0, "current_min": 6, "current_max": 16, "current_main": 25, "current_max_sum_mains": 600, "solar_max_import": 0, "solar_start_current": 4, "solar_stop_time": 10, "enable_C2": "Not present", "modem": "Not present", "mains_meter": "Sensorbox", "starttime": 0, "stoptime": 0, "repeat": 0 }, "mqtt": { "host": "xxx.xxx.xxx.xxx", "port": 1883, "topic_prefix": "SmartEVSE-xxxxx", "username": "xxxxxx", "password_set": 0, "status": "Connected" }, "home_battery": { "current": 0, "last_update": 0 }, "ev_meter": { "description": "Eastron3P", "address": 101, "import_active_power": 0, "total_kwh": 891.2, "charged_kwh": 14.8, "currents": { "TOTAL": 0, "L1": 0, "L2": 0, "L3": 0 }, "import_active_energy": 891.2, "export_active_energy": 0 }, "mains_meter": { "import_active_energy": 0, "export_active_energy": 0 }, "phase_currents": { "TOTAL": 159, "L1": 140, "L2": 6, "L3": 13, "last_data_update": 1711131319, "charging_L1": false, "charging_L2": false, "charging_L3": false, "original_data": { "TOTAL": 159, "L1": 140, "L2": 6, "L3": 13 } }, "backlight": { "timer": 0, "status": "OFF" } }
// SmartEVSE2
{ "version": "SERKRI-1.8.0", "mode": "SMART", "mode_id": 3, "car_connected": true, "wifi": { "status": "WL_CONNECTED", "ssid": "-", "rssi": -66, "bssid": "-" }, "evse": { "temp": 28, "temp_max": 65, "connected": true, "access": true, "mode": 1, "loadbl": 2, "pwm": 221, "solar_stop_timer": 0, "state": "Charging", "state_id": 2, "error": "None", "error_id": 0, "rfid": "Not Installed" }, "settings": { "charge_current": 130, "override_current": 0, "current_min": 6, "current_max": 16, "current_main": 25, "current_max_sum_mains": 600, "solar_max_import": 0, "solar_start_current": 4, "solar_stop_time": 10, "enable_C2": "Not present", "modem": "Not present", "mains_meter": "Sensorbox", "starttime": 0, "stoptime": 0, "repeat": 0 }, "mqtt": { "host": "xxx.xxx.xxx.xxx", "port": 1883, "topic_prefix": "SmartEVSE-xxxxx", "username": "", "password_set": 0, "status": "Connected" }, "home_battery": { "current": 0, "last_update": 0 }, "ev_meter": { "description": "Eastron3P", "address": 110, "import_active_power": 2.7, "total_kwh": 2.5, "charged_kwh": 0.9, "currents": { "TOTAL": 0, "L1": 0, "L2": 0, "L3": 0 }, "import_active_energy": 2.5, "export_active_energy": 0 }, "mains_meter": { "import_active_energy": 0, "export_active_energy": 0 }, "phase_currents": { "TOTAL": 159, "L1": 140, "L2": 6, "L3": 13, "last_data_update": 1711131313, "charging_L1": true, "charging_L2": true, "charging_L3": true, "original_data": { "TOTAL": 159, "L1": 140, "L2": 6, "L3": 13 } }, "backlight": { "timer": 120, "status": "ON" } }

[dingo35]

You'll have to upgrade to v3.5.0 when it comes out; if you like to test you can use current version v3.5.0-RC2.

Serkri was developed without test abilities for Master/Slave configurations, so you are on uncharted territories ...

[vdweegen]

Hi @dingo35 ,

Thanks for the quick reply. Can you verify my setup to be supported by v.3.5.0-RC2? Also, the lastest version I'm seeing is RC1.

[vdweegen]

I just installed v3.5.0-RC1, so far it works exactly as I was hoping. I'll keep testing. Great work!

[dingo35]

Excuse me, RC2 is the one we are currently working on, RC1 is the one you need.

There is a bug in RC1 that occasionally swaps EV Power charged and EV Energy Charged; if you dont log it with HomeAssistant you probably wont even notice, because that data is only displayed, not used in the algorythm.

So yes your setup is supported and no, it's not going to be bug free...

[vdweegen]

Cheers. If I run into any instabilities or bugs I'll be sure to let you know.

[dingo35]

Great! Please report on the appropriate repo.