this post was submitted on 03 Dec 2023
293 points (99.0% liked)
Technology
58591 readers
3870 users here now
This is a most excellent place for technology news and articles.
Our Rules
- Follow the lemmy.world rules.
- Only tech related content.
- Be excellent to each another!
- Mod approved content bots can post up to 10 articles per day.
- Threads asking for personal tech support may be deleted.
- Politics threads may be removed.
- No memes allowed as posts, OK to post as comments.
- Only approved bots from the list below, to ask if your bot can be added please contact us.
- Check for duplicates before posting, duplicates may be removed
Approved Bots
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Fibre optics can be used to measure a remarkable number of properties.
The electrical transmission industry makes significant use of fibreoptic current sensors, and distributed fibreoptic temperature sensors.
The latter is particularly useful as you can measure the temperature at any point along the fibre's length, allowing you to detect hot-spots in cables.
Cicadas are pretty loud; I'm sure you can pick up much quieter things with a fibreoptic microphone.
How does one measure temperature with a fiber? I’m a mechanical engineer that’s also worked as an electrical so you don’t have to dumb it down too much. I just doubt it’s as easy as you say
https://en.m.wikipedia.org/wiki/Distributed_temperature_sensing
I can't really explain it any better than Wikipedia. You absolutely need a special transceiver, but it looks like the basic answer is that hot bits show up slightly differently to cold bits when doing TDR or similar measurements.
You send a light pulse down the cable, you get light bouncing back from each point in the cable. The time between sending the pulse and when you measure the received signal is how far away you're measuring. Something about the received pulse - wavelength, power etc, allows you to estimate the temperature.
So, yeah. You build a fibre into your power cable, and plug one end into a box. It tells you the temperature of every meter of that fibre up to tens of kilometres, to within a degree.