iButton FAQ
Introduction
An iButton is a computer chip enclosed in a 16mm thick stainless steel can. Because of this unique and durable container, up-to-date information can travel with a person or object anywhere they go. The steel iButton device can be mounted virtually anywhere because it is rugged enough to withstand harsh environments, indoors or outdoors. It is small and portable enough to attach to a key fob, ring, watch, or other personal items, and be used daily for data logging tasks. iButtons are commonly mounted to storage crates, trucks, and other equipment for asset management. Furthermore, iButtons are mounted to refrigeration units, outdoor environments, and even to animals for various data logging tasks. Each iButton device has a unique and unalterable address laser etched onto its chip inside the can that can be used as a key or identifier for each iButton. iButtons are reusable and have an approximate 10 year battery life.
How Do I Get Information Into and Out of an iButton?
Information is transferred between your iButton and a PC with a momentary contact with an iButton Connectivity Kit at up to 142kbps. You simply touch your iButton to the blue dot receptor which is connected to a PC. The iButtons are setup (or "programmed") using the OneWireViewer software that comes with the Connectivity Kit. An iButton can be setup to record at intervals of between 1-255 minutes and when the temperature goes below or above user defined trip-points. That Connectivity Kit software also allows you to download and analyse the data. So the steps are:
1. Programme the iButtons using the Connnectivity Kit and software
2. Place the iButtons in the locations where you wish to record
3. After a period of time download the data from the iButtons using the Connectivity Kit and analyse
You can download the OneWireViewer software Quick Start Guide and Full Manual here:
OneWireViewer Quick Start Guide
What Operating Systems Are the iButtons Compatible With?
The included OnwWireViewer software is PC compatible only, Windows up to 10 (32 and 64 bit). It requires Java to run.
How Durable is an iButton?
The silicon chip within the iButton device is protected by the ultimate durable material: stainless steel. You can drop an iButton device, step on it, or scratch it. The iButton device is wear-tested for 10-year durability. The iButtons are rugged and are fine being in the rain (they have an IP56 rating). If you wish to sumbmerge them you will need a Waterproof iButton Capsule (compatible with DS1921, DS1922 and DS1925 series only).
Can the iButtons be Submerged in Water?
The iButton's steel enclosures are designed to withstand harsh environments, making these extremely reliable in a wide range of applications. While the iButtons are considered to be “water resistant” due to their IP56 (Ingress Protection) rating, they cannot be classified as waterproof, 
and should not be submerged unless accompanied by a DS9107 Waterproof Capsule.
Can I Use a DS9107 Waterproof Capsule with a Hygrochron DS1923 iButton?
The DS9107 waterproof capsule is designed as a protective enclosure that prevents the ingress of water and moisture. The DS1923 is a temperature and humidity logger, and while it can record temperature inside a DS9107 waterproof capsule, it cannot record accurate humidity readings for the ambient air (outside of the DS9107).
Can the DS1923 be Buried to Measure Soil Moisture?
The DS1923 cannot be used to measure soil moisture. When a DS1923 is buried the %RH will read 100+%. Also, it would 
likely be damaged due to water ingress over time.
What is the Expected Battery Life of an iButton?
The iButtons are designed to maximise energy efficiency. This focus has enabled iButtons to provide an impressive battery life performance. For example, a DS1921G logging temperature data every 10 minutes in the operating temperature range between -40°C to 40°C will surpass 7 years in battery life. The battery performance is dependent on a number of factors including:
1. Logging rate – faster logging rates consume more power.
2. Logger type – DS1921 models typically perform better from a battery life perspective.
3. Temperature range of operation – batteries perform best at room temperature moving to either extreme reduces performance.
4. Selected resolution (DS1922 & DS1923 only) – low resolution is more favourable to battery performance.
How Often Can the iButtons Take Readings?
The logging frequency supported by the iButtons varies by logger model. The DS1921 models can log temperature data every 1 to 255 minutes. The DS1922 & DS1923-F5# can record data every 1 sec to 273 hours.
Can the Software be Set Up on More than One PC?
Yes. The software can be set-up on multiple computers, the cable/adapter are needed at each computer to extract the data however.
How Do I Export iButton Data to Excel?
Download the guide on exporting to Excel here: