I have an underground Copper cable which is transmitting 12V , I want to use this cable for displaying temperature in a place which is as far as 5 kms , to my office , and I can't use any wireless protocol.
The 12V cable is already installed so I want to use this for communication. Can I use relays to convert 12V to 5V(1s) and 0s?
You can find 12V to 5V optocouplers
here is an example https://www.amazon.com/Icstation-Optocoupler-Isolation-Translator-Converter/dp/B06XKJGSXS
"underground cable transmitting 12V" - what's all this about?
Have you thought about LO-RA wireless which has a much greater range ?
Think you may have some issues with that distance using wire unless it is screened and twisted to prevent loops and other signal issues.
@zaibi123123 - from your description, you have a buried cable carrying 12V (DC?) and you want to somehow transmit data over the same 12V cable?
Is your cable 2-core? Are there any spare cores in your cable?
If no spare cores, then have a search for "serial data over power line".
Why can't you use wireless as just suggested?
Yes it's 2 core,Sorry it's the requirement of the project to be installed on telephone cable 12VDC. The medium can not be anything else except this
Not knowing much about voltage drop, but how much of your 12V is going to be left after 5km over telephone cable?
It's a telephone cable 12VDC 1 copper pair, and I have to utilize this to transfer data from temperature sensor to lcd display
Okay great , but will it not hinder the telephonic data going over the copper wires?, I have to use both side by side on same cables
Tell us if the telephone cable is STILL needed for telephone use!!!!
Yes they are needed😄
Then what you ask is impossible because the telephone uses DC on the wires to indicate to the central office when the hand set goes "off hook". When you pick up the hand set a switch is closed completing the circuit and indicating the telephone is in use.
May be you could double check if there are cable pairs that are unused in the phone cable. They often come with 2 or 4 pairs.
Depending where the telephone demark box is located, the wires may belong to the telephone company.
If these 'wires' are used for a utility company provided telephone connection, in a lot of places in the World, you need regulatory approval to connect to the wires ..............
Yes!
Well, if it's a telephone cable, put a modem at either end and send the data that way! That's what modems are for.