node red battery status% switsh feed in dc coupeld into grid on/off

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andre12 asked Sep 27, '23

node red battery status% switsh feed in dc coupeld into grid on/off

Hey

i need some help with Node red.

i have a Victron System as ESS with two MP2 5000/48 tow 150/100mppt and three Pylontec US2000

EM24 Cerbo

combined with a AC Thor 9S (Watter)

the AC Thor needs to have the Feed excess DC-coupled PV into grid aktive and on in order to work

But my Pylontech can only charge at maximum 75Ah

The problem is when there is to much Power(Feed excess DC power in) the system is excceding the max current on the Pylons

for now i i have to look every time if the Pylon is charged an then i can anable the Feed excess DC-coupled PV into grid thats verry odd

now i need help creating a flow that anabels the Feed excess DC-coupled PV into grid if the Pylon has reached 98%

and disabels if the Pylon falls under 97% or the feed in is more then 300W for more then like 10 Seconds

for right now i can shut the Feed excess DC-coupled PV into grid on and off via node red but not more

can someone please give me a hint how i can do that

Bye Andre

Node-RED

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Answer 1 · 2024-01-21T15:55:33Z

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

Answer 2 · 2024-03-29T19:07:10Z

h8mecz answered · Mar 29 at 07:07 PM

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.

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