Precision of sampling start time: Obtaining seconds from time_id or sensor RTC

Software
1

Hi NCD Team,

I am working with Industrial IoT Wireless Smart Vibration Sensor Gen4 and I have a question regarding the exact timestamp of when the recording/sampling process begins.

In the processed data, I see the received field, but I understand this is generated by the gateway and is subject to network latency and processing time.

In the raw data (Time Domain), there is a time_id field. From what I’ve observed, this seems to follow an HH:MM format. I have a couple of questions regarding this:

  1. Is there any way to obtain the time_id with seconds precision?
  2. If the sensor does not have a high-resolution RTC, is there any other register or field available in the payload that indicates the exact offset or uptime (in milliseconds or seconds) when the data capture started?

My goal is to align the raw data samples as accurately as possible with external events, so minimizing the “received vs sampled” uncertainty is critical for my application.

Thanks in advance for your help!

2

Hi @marinp28 Yes the msg.received is based on the Gateway’s time (It is the real time in which the gateway receives messages from sensors).

Yes, the msg.payload.sensor_data.time_id follow the HH:MM format, it is the time when the vibration reading was taken (by using the internal sensor RTC).

  1. It is not possible to obtain the time_id in seconds.
  2. It is not possible to get the exact time in seconds from sensor, but it can be estimated, you can use the msg.received property, for example; if you get the data at 10:30:25, it means the vibration data was captured around 4 seconds ago, 10:30:21.

Thank you.