Boah - what a coding! @E1cid you are a huge expert :). I'll never find such a code, but I can read it.
Your example works, but didn't update the "Old power" to the last period. I found the way. 
But one thing may be messy: My function node to store current values. (I can't use the output of the chart, because there the time is adjusted to the past.)
I'm sure you now how to transfer my function node to the change node "change for new data", or a seperate one.
I have in general trouble using JSONate. I found this description and this simulator, but it seems to be different the usage in Node-Red. e.g. your expression $number($moment().format("x")) will not work inside the simulator and the functions are not mentioned in the description.
Here is now my working flow, just reduced to a timeframe of 1 minute:
[
{
"id": "8a701c96ea9f2909",
"type": "ui_chart",
"z": "d1395164b4eec73e",
"name": "PV-Verlauf",
"group": "1234abcd",
"order": 0,
"width": 0,
"height": 0,
"label": "PV-Verlauf",
"chartType": "line",
"legend": "true",
"xformat": "HH:mm:ss",
"interpolate": "linear",
"nodata": "",
"dot": false,
"ymin": "",
"ymax": "",
"removeOlder": "60",
"removeOlderPoints": "",
"removeOlderUnit": "1",
"cutout": 0,
"useOneColor": false,
"useUTC": false,
"colors": [
"#1f77b4",
"#ff7f0e",
"#2ca02c",
"#d62728",
"#9467bd",
"#8c564b",
"#e377c2",
"#7f7f7f",
"#bcbd22"
],
"outputs": 1,
"useDifferentColor": false,
"className": "",
"x": 910,
"y": 720,
"wires": [
[
"c978733bb177459d"
]
]
},
{
"id": "c978733bb177459d",
"type": "debug",
"z": "d1395164b4eec73e",
"name": "chart",
"active": false,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "true",
"targetType": "full",
"statusVal": "",
"statusType": "auto",
"x": 1090,
"y": 720,
"wires": []
},
{
"id": "5f2e29a7c869120d",
"type": "change",
"z": "d1395164b4eec73e",
"name": "change old data to latest",
"rules": [
{
"t": "set",
"p": "topic",
"pt": "msg",
"to": "Old power",
"tot": "str"
},
{
"t": "set",
"p": "payload",
"pt": "msg",
"to": "(\t [\t {\t \"series\": [\"Old Power\", \"New Power\"],\t \"data\": [\t [],\t [] \t ] \t }\t ]\t)",
"tot": "jsonata"
},
{
"t": "set",
"p": "payload[0].data[0]",
"pt": "msg",
"to": "old",
"tot": "flow"
},
{
"t": "set",
"p": "old",
"pt": "flow",
"to": "[]",
"tot": "jsonata"
}
],
"action": "",
"property": "",
"from": "",
"to": "",
"reg": false,
"x": 610,
"y": 640,
"wires": [
[
"8a701c96ea9f2909",
"c3cfad7bb9e4bca0"
]
]
},
{
"id": "c3cfad7bb9e4bca0",
"type": "debug",
"z": "d1395164b4eec73e",
"name": "old",
"active": true,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "true",
"targetType": "full",
"statusVal": "",
"statusType": "auto",
"x": 1090,
"y": 640,
"wires": []
},
{
"id": "983fe8d85b3f4283",
"type": "inject",
"z": "d1395164b4eec73e",
"name": "every 5 sec",
"props": [
{
"p": "payload"
},
{
"p": "timestamp",
"v": "$number($moment().format(\"x\"))",
"vt": "jsonata"
},
{
"p": "topic",
"vt": "str"
}
],
"repeat": "5",
"crontab": "",
"once": true,
"onceDelay": 0.1,
"topic": "New power",
"payload": "$round($random(), 3)",
"payloadType": "jsonata",
"x": 230,
"y": 720,
"wires": [
[
"c81038ead8d5b188"
]
]
},
{
"id": "53e8601545abab1f",
"type": "inject",
"z": "d1395164b4eec73e",
"name": "reset chart",
"props": [
{
"p": "payload"
},
{
"p": "topic",
"vt": "str"
}
],
"repeat": "",
"crontab": "",
"once": false,
"onceDelay": 0.1,
"topic": "",
"payload": "[]",
"payloadType": "json",
"x": 220,
"y": 780,
"wires": [
[
"8a701c96ea9f2909"
]
]
},
{
"id": "c1a991f3a8115cd3",
"type": "change",
"z": "d1395164b4eec73e",
"name": "init chart",
"rules": [
{
"t": "set",
"p": "payload",
"pt": "msg",
"to": "(\t $fiveminsago := $number($moment().subtract(1,\"minute\").format(\"x\"));\t [\t {\t \"series\": [\"Old Power\", \"New Power\"],\t \"data\": [\t [\t [\t 0,\t 1,\t 2,\t 3,\t 4,\t 5,\t 6,\t 7,\t 8,\t 9,\t 10,\t 11\t ].{\"x\": $fiveminsago + ($ * 60000), \"y\": $round($random(), 3)} \t ],[] \t ] \t }\t ]\t)",
"tot": "jsonata"
}
],
"action": "",
"property": "",
"from": "",
"to": "",
"reg": false,
"x": 660,
"y": 580,
"wires": [
[
"8a701c96ea9f2909",
"40c6c0e3ffcb57eb"
]
]
},
{
"id": "5fb141bc640dce0d",
"type": "switch",
"z": "d1395164b4eec73e",
"name": "",
"property": "old",
"propertyType": "flow",
"rules": [
{
"t": "null"
},
{
"t": "else"
}
],
"checkall": "true",
"repair": false,
"outputs": 2,
"x": 410,
"y": 600,
"wires": [
[
"c1a991f3a8115cd3"
],
[
"5f2e29a7c869120d"
]
]
},
{
"id": "40c6c0e3ffcb57eb",
"type": "debug",
"z": "d1395164b4eec73e",
"name": "init",
"active": true,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "payload",
"targetType": "msg",
"statusVal": "",
"statusType": "auto",
"x": 1070,
"y": 580,
"wires": []
},
{
"id": "c81038ead8d5b188",
"type": "function",
"z": "d1395164b4eec73e",
"name": "save value",
"func": "let old = flow.get(\"old\") || [];\n\nlet value = {x:msg.timestamp, y:msg.payload};\nold.push(value);\nflow.set(\"old\",old);\n\nreturn msg;",
"outputs": 1,
"timeout": 0,
"noerr": 0,
"initialize": "",
"finalize": "",
"libs": [],
"x": 410,
"y": 720,
"wires": [
[
"8d08e21e3af47f2a",
"91ca458babbf9511"
]
]
},
{
"id": "8d08e21e3af47f2a",
"type": "change",
"z": "d1395164b4eec73e",
"name": "change for new data",
"rules": [
{
"t": "set",
"p": "timestamp",
"pt": "msg",
"to": "$number($moment().subtract(1 ,\"minute\").format(\"x\"))",
"tot": "jsonata"
},
{
"t": "set",
"p": "topic",
"pt": "msg",
"to": "New Power",
"tot": "str"
}
],
"action": "",
"property": "",
"from": "",
"to": "",
"reg": false,
"x": 654,
"y": 716,
"wires": [
[
"8a701c96ea9f2909",
"717ec4894c0aeea8"
]
]
},
{
"id": "9f734376fdca9d9b",
"type": "inject",
"z": "d1395164b4eec73e",
"name": "every minute",
"props": [
{
"p": "payload"
},
{
"p": "topic",
"vt": "str"
}
],
"repeat": "60",
"crontab": "",
"once": true,
"onceDelay": 0.1,
"topic": "",
"payload": "",
"payloadType": "date",
"x": 240,
"y": 600,
"wires": [
[
"5fb141bc640dce0d"
]
]
},
{
"id": "717ec4894c0aeea8",
"type": "debug",
"z": "d1395164b4eec73e",
"name": "time",
"active": false,
"tosidebar": true,
"console": false,
"tostatus": true,
"complete": "timestamp",
"targetType": "msg",
"statusVal": "timestamp",
"statusType": "auto",
"x": 864,
"y": 796,
"wires": []
},
{
"id": "91ca458babbf9511",
"type": "debug",
"z": "d1395164b4eec73e",
"name": "time",
"active": false,
"tosidebar": true,
"console": false,
"tostatus": true,
"complete": "timestamp",
"targetType": "msg",
"statusVal": "timestamp",
"statusType": "auto",
"x": 670,
"y": 800,
"wires": []
},
{
"id": "1234abcd",
"type": "ui_group",
"name": "PV-Anlage",
"tab": "494ffd2f5ab44ab2",
"order": 1,
"disp": true,
"width": "6",
"collapse": false,
"className": ""
},
{
"id": "494ffd2f5ab44ab2",
"type": "ui_tab",
"name": "Dashboard",
"icon": "dashboard",
"order": 1,
"disabled": false,
"hidden": false
}
]
BTW: How can I post the flow in one line? I read this post, but the link for description of how to post a flow is broken.
