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Product Briefing Outline: The HTZ Smart ‘HART’ Humidity and Temperature Transmitter from Moore Industries simultaneously measures temperature and humidity in processes that require extremely close monitoring of humidity, temperature and dewpoint. This includes cleanrooms, assembly areas and storage facilities. The unit can be programmed or queried from any point along one of the transmitter’s dual 4-20mA loops. 

Problem: Many accurate humidity transmitters are available on the market, but few also have an accurate temperature measurement. Calculating dewpoint requires accuracy in both measurements. Previous solutions would combine an expensive humidity instrument with a highly accurate temperature transmitter, such as the Moore Industries TRX, which was twice as expensive as the new solution.

Solution: The loop-powered (2-wire) HTZ provides the required measurement accuracy for humidity, temperature and dewpoint in a single instrument, which eliminates the cost of using multiple transmitters. Accuracy of the relative humidity measurements is up to ±0.75%RH, the temperature measurement is up to ±0.036°C, and the dewpoint calculation is within ±0.5°C. The HTZ incorporates a sensor module which consists of two parallel probes, one containing a capacitance-based humidity sensor and the other containing a highly-accurate temperature sensor. The sensor module can be mounted on any surface or pipe, such as a HVAC duct or a cleanroom wall. Either probe can be removed for easy cleaning, calibration or replacement. The HTZ also incorporates a humidity and temperature display module that can be mounted up to 30 feet away from the sensor module. The display module provides power to the sensor probes and produces two 4-20mA output signals. Each output can be programmed to represent relative humidity, temperature or dewpoint.  The display can be programmed to show humidity, temperature, dewpoint, analog output #1, analog output #2 or scroll between the values.

Applications: The HTZ operates in temperatures from -40 to 185°F (-40 to 85°C), allowing installation in almost all environments, indoors and outdoors.

Platform: PC-based or HART-based configuration: the HTZ can be programmed on site in minutes, using free Intelligent PC Configuration software, a HART-based system, or by using a standard hand-held HART Communicator from any point along the 4-20mA loop.  

Availability: May 2008 onwards.