Inserting data with timestamp in MongoDB

Hi all,
I am trying to learn the basics of MongoDB to insert some process data from a PLC so that another application of a partner uses this data in realtime.
I would use Node-RED to read the data from the Siemens PLC (using S7 node) and inserting it into the MongoDB data base. I am trying the nodes of Node-red-node-mongodb.

I have created a data base for trials with a timeseries collection. So the inserted document must include a time field, but I am not being able to do it correctly.
I inject the "timestamp" value, but it isn't recogniced as a correct time field and cannot be inserted in the MongoDB data base.

How should I do it? (please, take into account that my programming background is very poor).

Thanks in advance and best regards

hi .. are you sending your "timestamp" field as a Date or is it a String and its failing ?
I did some quick test with a timeseries collection and this worked for me

Function node to prepare a msg.payload for the mongodb out node set to Insert :

msg.payload = {
    "timestamp": new Date(),
    "value1": 33,
    "value2": 12
}

return msg;

Flow:

[{"id":"dc742398782aab73","type":"inject","z":"54efb553244c241f","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":220,"y":1080,"wires":[["07beb63e4e603c82"]]},{"id":"07beb63e4e603c82","type":"function","z":"54efb553244c241f","name":"function 1","func":"msg.payload = {\n    \"timestamp\": new Date(),\n    \"value1\": 33,\n    \"value2\": 12\n}\n\nreturn msg;","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":460,"y":1080,"wires":[["79b70be061685cef","676f99158b209fc6"]]},{"id":"79b70be061685cef","type":"debug","z":"54efb553244c241f","name":"debug","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":590,"y":980,"wires":[]},{"id":"676f99158b209fc6","type":"mongodb out","z":"54efb553244c241f","mongodb":"39adf9d0.a8c876","name":"","collection":"test2","payonly":true,"upsert":false,"multi":false,"operation":"insert","x":730,"y":1080,"wires":[]},{"id":"39adf9d0.a8c876","type":"mongodb","hostname":"localhost","topology":"direct","connectOptions":"useUnifiedTopology=true","port":"27017","db":"nodered","name":""}]

If you give us more information of the stucture of data that come from the S7 node maybe we can help
to tweak the code based on your project.