Ahh, I see what the problem is here. The "split" node only operates on the base msg.payload
object. I added a "chnage" node to extract the measurements array in the following example. Then the split works as expected. I also added a converter for the timestamp so that is converted to the proper Lynx-format. The debug-node in the end of this chain can be replaced with the Lynx-out node to send data to the platform.
[{"id":"fcd13b9af3a32a58","type":"inject","z":"c93b27d19fe7d6ca","name":"Base Data","props":[{"p":"payload"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"id\":100544,\"resolution\":\"Hour\",\"measurements\":[{\"timeStamp\":\"2023-10-19T01:00:00\",\"value\":854.1},{\"timeStamp\":\"2023-10-19T02:00:00\",\"value\":856.5},{\"timeStamp\":\"2023-10-19T03:00:00\",\"value\":891.6},{\"timeStamp\":\"2023-10-19T04:00:00\",\"value\":885.6},{\"timeStamp\":\"2023-10-19T05:00:00\",\"value\":864.9},{\"timeStamp\":\"2023-10-19T06:00:00\",\"value\":852.3},{\"timeStamp\":\"2023-10-19T07:00:00\",\"value\":910.2},{\"timeStamp\":\"2023-10-19T08:00:00\",\"value\":939},{\"timeStamp\":\"2023-10-19T09:00:00\",\"value\":956.4},{\"timeStamp\":\"2023-10-19T10:00:00\",\"value\":905.7},{\"timeStamp\":\"2023-10-19T11:00:00\",\"value\":909.6},{\"timeStamp\":\"2023-10-19T12:00:00\",\"value\":978.6},{\"timeStamp\":\"2023-10-19T13:00:00\",\"value\":1059.9},{\"timeStamp\":\"2023-10-19T14:00:00\",\"value\":950.7},{\"timeStamp\":\"2023-10-19T15:00:00\",\"value\":831},{\"timeStamp\":\"2023-10-19T16:00:00\",\"value\":875.7},{\"timeStamp\":\"2023-10-19T17:00:00\",\"value\":921},{\"timeStamp\":\"2023-10-19T18:00:00\",\"value\":904.2},{\"timeStamp\":\"2023-10-19T19:00:00\",\"value\":899.7},{\"timeStamp\":\"2023-10-19T20:00:00\",\"value\":933},{\"timeStamp\":\"2023-10-19T21:00:00\",\"value\":957.6},{\"timeStamp\":\"2023-10-19T22:00:00\",\"value\":944.7},{\"timeStamp\":\"2023-10-19T23:00:00\",\"value\":896.1},{\"timeStamp\":\"2023-10-20T00:00:00\",\"value\":858.9}]}","payloadType":"json","x":320,"y":200,"wires":[["45968cb13757e58f"]]},{"id":"5b73ffb2ff6a9d92","type":"debug","z":"c93b27d19fe7d6ca","name":"debug 1","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":1100,"y":200,"wires":[]},{"id":"1eafd8f3ea2d9912","type":"split","z":"c93b27d19fe7d6ca","name":"","splt":"\\n","spltType":"str","arraySplt":1,"arraySpltType":"len","stream":false,"addname":"","x":670,"y":200,"wires":[["61d41bd034374b26"]]},{"id":"45968cb13757e58f","type":"change","z":"c93b27d19fe7d6ca","name":"","rules":[{"t":"set","p":"payload","pt":"msg","to":"payload.measurements","tot":"msg","dc":true}],"action":"","property":"","from":"","to":"","reg":false,"x":500,"y":200,"wires":[["1eafd8f3ea2d9912"]]},{"id":"61d41bd034374b26","type":"function","z":"c93b27d19fe7d6ca","name":"Convert Date to Unix-time","func":"msg.payload.timestamp = new Date(msg.payload.timeStamp).getTime() / 1000\ndelete msg.payload.timeStamp\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":870,"y":200,"wires":[["5b73ffb2ff6a9d92"]]}]