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I'm planning Raspberry Pi system using One-Wire with thermometers (ca 10 pcs). My electrical skills are basic. I'm looking for a good way connecting stubs to main line.

Raspberry Pi + 1-Wire .

The main line (green) 1 planned to use CAT5 with shielding, expected length 10m.

The stubs (blue) with thermometers cable is not decided yet, but thinking about 3 conductors with shielding. Stub lengths max 0.5-1m.

My question is about connecting stubs to main line - what could be most practical way doing it? I don't want to solder them as I consider it too monolithic. Would screw terminals be good idea for this? I would like to build it by extending it piece by piece.

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  • \$\begingroup\$ I am currently facing the same question, actually. My current thinking is to just use simple RJ45 T-shaped splitters at every stub. Haven't tested it myself, so I was looking someone who actually did. This blog post does something similar, albeit using telephone cable and corresponding RJ11 connectors: nuewire.com/2011/04/easy-arduino-1-wire-sensor-network \$\endgroup\$ – martyn Apr 30 '18 at 20:48
  • \$\begingroup\$ I'd say use a coaxial and use the shield as ground. There are T connectors anf what not readily available. \$\endgroup\$ – Jan Dorniak Apr 30 '18 at 21:54
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I used telephone sockets and splitters purchased at a €2 store without trouble.

  • CAT5 loops through the telephone sockets.
  • Cut a phone lead to the required length and solder the wires onto the 1-wire sensor.

enter image description here

Figure 1. Be aware that most telephone leads have the plugs oriented with the latch on the ribbed side of the cable (or the same side of the cable) which means that colour sequence is opposite at each end.

I strongly suggest that you pick one pattern and throw the other end away or you will go slowly bonkers soldering and debugging.

enter image description here

Figure 2. A 1-wire shield for the Raspberry Pi simplifies the protocol. Source: AB Electronics.

I recommend the extra cost of a shield for this as it removes any timing issues which will arise if you try to connect directly to the Pi GPIO. See the link.

I had no problems with 1 m stubs from the telephone sockets with half a dozen sensors on a 25 m run.

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