Product Overview; Overview Of Hmt140 Features; Data Management; Models - Vaisala HMT140 User Manual

2. Product Overview
2.1 Overview of HMT140 Features
The Vaisala Wi-Fi Data Logger HMT140 measures relative humidity and temperature using the
connected probe and analog signals – RTD, Voltage, Current Loops and Boolean Contacts. The
HMT140 comes with or without an optional LCD display.
The HMT140 supports several different signal measurements (channels), which are monitored
in Vaisala viewLinc Enterprise Server software:
• Relative Humidity (RH)
• Temperature (T)
• Switch Contact
• Voltage and Current
Channel types are set at the factory during the time of order. Other wireless parameters can be
changed at a later date using an HMT140 Configuration Cable and Vaisala HMT140 Utility
software.
More Information
‣ Options and Accessories (page 10)
2.1.1 Data Management
An HMT140 can store several thousands of records before needing to overwrite data. In the
event of a communication problem, the HMT140 will continue to log and store data until it has
collected 3060 records per channel and then it will begin overwriting data.
For example, if an HMT140 is configured with a 5-minute sample rate, it will continue to log
data for approximately 10 days before overwriting data.
2.1.2 Models
The following HMT140 models and options are available:
• HMT141: Vaisala HUMICAPâ Humidity and Temperature Probe (RH/T)
• HMT143: Dual RTD Temperature Inputs w/5 m Probes (-90 to +90 °C (-130 to +194 °F))
• HMT144: Voltage Inputs (0 ... 5 VDC)
• HMT145: Voltage inputs (0 ... 10 VDC)
• HMT146: Current Inputs (0 ... 20 mA)
• HMT147: Boolean Inputs
• HMT148: RTD Temperature Input w/5 m Probe and Boolean Input
• HMT14C: RTD Inputs (customer-supplied Probe)
• HMT14D: RTD and Current Input
• HMT14E: RTD and Voltage Input (0 ... 5 VDC)
• HMT14F: RTD and Voltage Input (0 ... 10VDC)
Chapter 2 – Product Overview
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