--- title: Simple Multi-Room Temperature Monitoring with Dallas... description: A DIY multi-room temperature monitoring project using Dallas DS18S20 one-wire sensors wired through existing Cat5 infrastructure. The setup uses an iButtonLink... canonical: https://daily.dev/posts/simple-multi-room-temperature-monitoring-with-dallas-one-wire-5njkdjbk6 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Simple Multi-Room Temperature Monitoring with Dallas One-Wire | daily.dev og:description: A DIY multi-room temperature monitoring project using Dallas DS18S20 one-wire sensors wired through existing Cat5 infrastructure. The setup uses an iButtonLink... og:url: https://daily.dev/posts/simple-multi-room-temperature-monitoring-with-dallas-one-wire-5njkdjbk6 og:image: https://api.daily.dev/og/posts/5njKDjbk6.png og:image:alt: Simple Multi-Room Temperature Monitoring with Dallas One-Wire og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Simple Multi-Room Temperature Monitoring with Dallas One-Wire **[apalrd's adventures](https://daily.dev/sources/apalrd)** · 4 min read · 0 upvotes · 0 comments ## Summary A DIY multi-room temperature monitoring project using Dallas DS18S20 one-wire sensors wired through existing Cat5 infrastructure. The setup uses an iButtonLink LinkUSB USB master, OWFS for bus reading, and has evolved over time from EmonCMS on FreeNAS to Node-Red with InfluxDB and Grafana on a Raspberry Pi, and later partially migrated to Home Assistant. Practical lessons include using Cat5e pairs instead of cheap phone wire for soldering, adding a second LinkUSB to handle longer bus lengths, and potting outdoor sensors to prevent corrosion. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Can Dallas DS18S20 one-wire sensors work in a star topology wiring setup? Dallas DS18S20 sensors can work in a star topology at decently short lengths. Using existing Cat5 wiring in walls is viable, but longer runs with many splits can cause read failures. Adding a second bus master (LinkUSB) to split the network in half helps when the wiring length grows and some sensors become difficult to read reliably. _Makers expanding one-wire sensor networks share topology lessons like these on daily.dev._ ### What is the best wire to use for soldering Dallas DS18S20 TO-92 sensors? A single pair pulled from a Cat5e bundle works better than cheap stranded phone wire for soldering to DS18S20 TO-92 sensors. Stranded phone wire is acceptable for crimping RJ11 connectors but is difficult to strip and solder cleanly. Cat5e pairs crimp well to RJ11 center pins and solder reliably to the sensor leads. _Hardware hackers building sensor networks find practical wiring tips like this on daily.dev._ ### How do I protect outdoor Dallas DS18S20 sensors from corrosion? Outdoor DS18S20 sensors should be hot glued or potted to protect the point where heat shrink meets the TO-92 package. Without this protection, moisture causes corrosion at that junction and leads to sensor failure. Indoor sensors using only heat shrink have proven reliable over multiple years without additional protection. _Builders deploying outdoor IoT sensors track failure modes and fixes like this on daily.dev._ ## Similar posts on daily.dev - [I built a cheap ESP32 weather station to automate my Home Assistant server](https://daily.dev/posts/i-built-a-cheap-esp32-weather-station-to-automate-my-home-assistant-server-vjfkl9qcz) · XDA Developers · 0 upvotes · 0 comments - [Environmental Monitoring On The Cheap](https://daily.dev/posts/environmental-monitoring-on-the-cheap-61ddhyufc) · Hackaday · 0 upvotes · 0 comments - [DIY ESP32-P4 weather station & air quality monitor connects to LoRa and ESP-NOW sensors, various weather APIs](https://daily.dev/posts/diy-esp32-p4-weather-station-air-quality-monitor-connects-to-lora-and-esp-now-sensors-various-wea-fyniccq3k) · CNX Software · 0 upvotes · 0 comments - [Simplifying Embedded System Design with a Modern Software Ecosystem](https://daily.dev/posts/simplifying-embedded-system-design-with-a-modern-software-ecosystem-jr0ummxbk) · Embedded.com · 0 upvotes · 0 comments - [Home Assistant solved three annoying problems I didn't know sensors could fix](https://daily.dev/posts/home-assistant-solved-three-annoying-problems-i-didn-t-know-sensors-could-fix-hqehpr5t2) · XDA Developers · 0 upvotes · 0 comments --- Tags: [#raspberry-pi](https://daily.dev/tags/raspberry-pi), [#grafana](https://daily.dev/tags/grafana), [#influxdb](https://daily.dev/tags/influxdb) [View this post on daily.dev](https://daily.dev/posts/simple-multi-room-temperature-monitoring-with-dallas-one-wire-5njkdjbk6) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Simple Multi-Room Temperature Monitoring with Dallas One-Wire","url":"https://daily.dev/posts/simple-multi-room-temperature-monitoring-with-dallas-one-wire-5njkdjbk6","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/simple-multi-room-temperature-monitoring-with-dallas-one-wire-5njkdjbk6"},"datePublished":"2026-08-11T08:56:34.481Z","dateModified":"2026-08-11T09:43:52.411Z","description":"A DIY multi-room temperature monitoring project using Dallas DS18S20 one-wire sensors wired through existing Cat5 infrastructure. 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