Introduction to HMT130 - HMT130

HMT130 User Guide

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User guide

Vaisala HMT130 Series HUMICAP® Humidity and Temperature Transmitters measure relative humidity and temperature and convert the measurements to voltage outputs and RS-485. Other measurement parameters, such as dew point (Td) can be calculated from the basic RH and T values according to the device configuration. HMT130 is powered with a 10 … 35 V DC or a 24 V AC supply (15 … 35 V DC or 24 V AC required when using 0 … 10 V output). It outputs two analog voltage signals with nominal 0 … 10 V range. HMT130 has also an RS-485 digital interface and a relay.

The HMP110 series measurement probes used with HMT130 incorporate the reliable Vaisala HUMICAP® humidity sensor technology.

The HMT130 transmitter's output parameters are configurable. Available parameters for outputs are limited to two at a time. These two parameters can be used freely at any outputs (display, service port, and voltage outputs).

Available parameters are RH, T, Td, Td/f, a, x, h, Tw, pws, and pw.

The default output parameters are set at the factory during order time. These factory preset parameters selections can be changed afterwards via the service port if necessary.

The TMT130 transmitter is a single-parameter model, with temperature as the only output parameter.

Vaisala relative humidity measurement instruments

The Vaisala range of relative humidity measurement instruments covers all the applications from ventilation to process control in demanding conditions. For more information about other Vaisala relative humidity instruments, please contact your Vaisala representative or visit