question

Hey Andre,

@Andre12 because we are both speaking german and no other replyed jet, here in german:

Aktuell habe ich ein sehr ähnliches Problem:
Wenn DC-FeedIn aktiv ist wird ja (wieso auch immer) die Stromvorgabe des BMS ignoriert.

Ich möchte gerne aber den Ladestrom unterbinden, wenn eine Zelle peaken (über 3,55V) würde.
Hierzu lese ich das Modbusregister (mit node-red-contrib-modbus) der maximalen Zellspannung aus und deaktiviere das Einspeisen wenn nötig. Dadurch greift wieder die Stromvorgabe und der Akku und ich bleiben glücklich.

Hier die JSON zum direkt importieren:

[{"id":"a84a659d3a364463","type":"modbus-read","z":"f6f2187d.f17ca8","name":"MaxCellV * 100","topic":"","showStatusActivities":false,"logIOActivities":false,"showErrors":false,"showWarnings":true,"unitid":"225","dataType":"InputRegister","adr":"1291","quantity":"1","rate":"10","rateUnit":"s","delayOnStart":false,"startDelayTime":"","server":"54c58588b799b323","useIOFile":false,"ioFile":"","useIOForPayload":false,"emptyMsgOnFail":false,"x":160,"y":1020,"wires":[["a1d6e770670e0a1f"],[]]},{"id":"d3bfae01833d48c7","type":"debug","z":"f6f2187d.f17ca8","name":"debug 1","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":560,"y":980,"wires":[]},{"id":"3f6927494cfc0336","type":"hysteresis","z":"f6f2187d.f17ca8","name":"","ThresholdType":"fixed","ThresholdRising":"355","ThresholdFalling":"351","TopicThreshold":"","TopicCurrent":"","ThresholdDeltaRising":"","ThresholdDeltaFalling":"","InitialMessage":false,"OutRisingType":"num","OutRisingValue":"0","OutFallingType":"num","OutFallingValue":"1","OutTopicType":"top","OutTopicValue":"","DynRaiseError":false,"x":570,"y":1020,"wires":[["e5f3d8ae98b8abc6"]]},{"id":"2874a196059d975d","type":"comment","z":"f6f2187d.f17ca8","name":"Schutz gegen Überspannung","info":"Bei aktiviertem DC-feedin wird Currenlinkit vo BMS ignoriert\n\n-> bei zu hoher Zellspannung wird DC Einspeisung verhindert,\ndamit Linit wider eingehalten wird","x":820,"y":980,"wires":[]},{"id":"a1d6e770670e0a1f","type":"function","z":"f6f2187d.f17ca8","name":"Array auflösen","func":"msg.payload = msg.payload[0]\nreturn msg;","outputs":1,"timeout":"","noerr":0,"initialize":"","finalize":"","libs":[],"x":380,"y":1020,"wires":[["3f6927494cfc0336","d3bfae01833d48c7"]]},{"id":"e5f3d8ae98b8abc6","type":"modbus-write","z":"f6f2187d.f17ca8","name":"DC FeedIn","showStatusActivities":false,"showErrors":false,"showWarnings":true,"unitid":"100","dataType":"HoldingRegister","adr":"2707","quantity":"1","server":"54c58588b799b323","emptyMsgOnFail":false,"keepMsgProperties":false,"delayOnStart":false,"startDelayTime":"","x":770,"y":1020,"wires":[[],[]]},{"id":"d48ded7aaeae492d","type":"inject","z":"f6f2187d.f17ca8","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"1","payloadType":"num","x":550,"y":1080,"wires":[["e5f3d8ae98b8abc6"]]},{"id":"29842c3a2bc60ee4","type":"inject","z":"f6f2187d.f17ca8","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"0","payloadType":"num","x":550,"y":1120,"wires":[["e5f3d8ae98b8abc6"]]},{"id":"54c58588b799b323","type":"modbus-client","name":"Cerbo","clienttype":"tcp","bufferCommands":true,"stateLogEnabled":false,"queueLogEnabled":false,"failureLogEnabled":true,"tcpHost":"192.168.5.90","tcpPort":"502","tcpType":"DEFAULT","serialPort":"/dev/ttyUSB","serialType":"RTU-BUFFERD","serialBaudrate":"9600","serialDatabits":"8","serialStopbits":"1","serialParity":"none","serialConnectionDelay":"100","serialAsciiResponseStartDelimiter":"0x3A","unit_id":"1","commandDelay":"1","clientTimeout":"1000","reconnectOnTimeout":true,"reconnectTimeout":"2000","parallelUnitIdsAllowed":true,"showWarnings":true,"showLogs":true}]

Grüße Sebastian

Hi guys, I am facing exactelly this problem overcurrent becase DVCC is not working during grid feed in. And exactely this node red flow was in my head to solve somehow this issue! It is not 100% solution but better than nothing.