The DS1923 temperature/humidity logger iButton® is a rugged, self-sufficient system that measures temperature and/or humidity and records the result in a protected memory section. The recording is done at a user-defined rate. A total of 8192 8-bit readings or 4096 16-bit readings taken at equidistant intervals ranging from 1s to 273hrs can be stored. In addition to this, there are 512 bytes of SRAM for storing application-specific information and 64 bytes for calibration data. A mission to collect data can be programmed to begin immediately, or after a userdefined delay or after a temperature alarm. Access to the memory and control functions can be passwordprotected.
The DS1923 is configured and communicates with a host-computing device through the serial 1-Wire protocol, which requires only a single data lead and a ground return. Every DS1923 is factory-lasered with a guaranteed unique 64-bit registration number that allows for absolute traceability. The durable stainless-steel package is highly resistant to environmental hazards such as dirt, moisture, and shock. Accessories permit the DS1923 to be mounted on almost any object, including containers, pallets and bags.
Features
- Operating Range: -20 to +85°C; 0 to 100%RH (see Safe Operating Range in datasheet)
- Digital Hygrometer Measures Humidity with 0.6%RH or 0.04%RH Resolution
- Automatically Wakes Up, Measures Temperature and/or Humidity and Stores up to 8192 Values in 8KB of Datalog Memory
- Digital Thermometer Measures Temperature with 0.5°C or 0.0625°C Resolution
- Temperature Accuracy Better than ±0.5°C from -10°C to +65°C with Software Correction
- Sampling Rate from 1s up to 273hrs
- Built-in Humidity Sensor for Simultaneous Temperature and Humidity Logging
- Capacitive Polymer Humidity-Sensing Element Hydrophobic Filter Protects Sensor Against Dust, Dirt, Contaminants, and Water Droplets/Condensation
- Programmable Recording Start Delay After Elapsed Time or Upon a Temperature Alarm Trip Point
- Programmable High and Low Trip Points for Temperature and Humidity Alarms
- Quick Access to Alarmed Devices Through 1-Wire® Conditional Search Function
- 512 Bytes of General-Purpose Memory Plus 64 Bytes of Calibration Memory
- Two-Level Password Protection of All Memory and Configuration Registers
- Communicates to Host with a Single Digital Signal at Up to 15.4kbps at Standard Speed or Up to 125kbps in Overdrive Mode Using 1-Wire Protocol
Common iButton Features
- Digital identification and information by momentary contact.
- Unique factory-lasered 64-bit registration number assures error free device selection and absolute traceability because no two parts are alike.
- Built-in multidrop controller for 1-Wire net.
- Chip-based data carrier compactly stores information.
- Data can be accessed while affixed to object.
- Button shape is self-aligning with cup-shaped probes.
- Durable stainless-steel case engraved with registration number withstands harsh environments.
- Easily affixed with self-stick adhesive backing, latched by its flange, or locked with a ring pressed onto its rim.
- Presence detector acknowledges when reader first applies voltage.
- Meets UL#913 (4th Edit.); Intrinsically Safe Apparatus: approved under Entity Concept for use in Class I, Division 1, Group A, B, C, and D Locations.
Application
The DS1923 is an ideal device to monitor for extended periods of time the temperature and humidity of any object it is attached to or shipped with, such as fresh produce, medical drugs and supplies and for use in refrigerators and freezers, as well as for logging climatic data during the transport of sensitive objects and critical processes such as curing. A 1.27mm diameter hole in the lid of the device allows for air to reach the humidity sensor. The rest of the electronics inside the DS1923 is sealed so that it is not exposed to ambient humidity.
Note that the initial sealing level of DS1923 achieves IP56. Aging and use conditions can degrade the integrity of the seal over time, so for applications with significant exposure to liquids, sprays, or other similar environments, it is recommended to place the Hygrochron under a shield to protect it (see datasheet).
F5 MicroCAN
