Until the early 1970s, hair hygrometers were commonly used in radiosondes. At that time, reliable humidity measurement was an unresolved challenge and to solve this, Vaisala began developing a new type of humidity sensor using semiconductors and thin-film materials. The revolutionary HUMICAP humidity sensor was introduced two years later, in 1973, at CIMO VI Congress. HUMICAP was a radical innovation that changed humidity measurements for good. The new technology was groundbreaking: the sensor had no moving parts, and due to the advanced use of semiconductor and thin-film technologies, it was amazingly small. The sensor had a fast response time, good linearity, low hysteresis, and small temperature coefficiency.
Despite the fact that the innovation was designed for a new type of a radiosonde, the greatest interest came from elsewhere: people working in environments as diverse as greenhouses, bakeries, warehouses, construction sites, brick and timber kilns, and museums. The need for reliable humidity measurement was common to all, and instruments that could do this accurately were few and far between. By 1980, a variety of products based on HUMICAP technology – from hand-held meters to industrial transmitters, calibrators, and other accessories – were being sold in over 60 countries. Since its birth, HUMICAP has been part of Vaisala’s core business, propelling the company to industry leadership in the field of humidity measurement.
The HUMICAP sensor offers several unique benefits:
- Excellent long-term stability
- Insensitive to dust and most chemicals
- Chemical purge option for stable measurements in environments with high concentrations of chemicals
- Sensor heating for measurements even in condensing environments
- Full recovery from condensation
Following are a few of VAISALA’s humidity products, available from ESIS, that utilise the revolutionary HUMICAP technology:
HUMICAP Humidity and Temperature Probe HMP113
The Vaisala HUMICAP HMP113 humidity probe with plastic enclosure has excellent reliability and high chemical tolerance and is suitable for non-condensing environments with fast temperature changes and a need for high accuracy measurements with traceability.
HUMICAP Humidity and Temperature Probe HMP155
Vaisala’s HUMICAP HMP155 is a plug-and-play sensor that has excellent stability and withstands well even in harsh environments. The probe provides reliable humidity and temperature measurement and it is designed specifically for demanding outdoor applications.
HUMICAP OEM Modules for relative humidity, temperature and dew point applications
Vaisala offers a wide range of OEM modules for relative humidity (RH), temperature (T) and dewpoint (Td) measurement applications.
Humidity Module HMM100 for Environmental Chambers
Practically maintenance-free HMM100 is an open frame module for integration into environmental chambers. Excellent measurement accuracy with Vaisala HUMICAP 180R2 sensor.
Digital Open Frame Humidity Module HMM105 for OEM Applications
An open frame module for integration into environmental chambers and incubators. The module incorporates the Vaisala HUMICAP 180R sensor which ensures excellent measurement accuracy. A reliable choice for OEM use.
Humidity and Temperature Transmitter Series HMT310 for Demanding Industrial Applications
The Vaisala HUMICAP HMT310 series is for demanding industrial applications where compact product design. The measurement stability is excellent. The instrument is easy to integrate, small in size and insensitive to dust and most chemicals. The HMT310 series features several probe options for different application needs:
- HMT311 for wall mounting
- HMT313 for general use
- HMT314 for high pressures up to 100 bar and vacuum conditions
- HMT315 for high temperatures
- HMT317 for high humidity and meteorological applications
- HMT318 for pressurized pipelines up to 40 bar
Select the best humidity sensor to suit your needs
Selecting a suitable humidity sensor for a particular application is not a trivial task. There are lots of issues to consider, and choosing the wrong sensor could result in an early sensor failure or incorrect operation. This could cost your operation a lot of wasted time and money.
The easy way to be sure that you get the right sensor, is to contact ESIS and discuss your needs.
Since it’s initiation in 1971 ESIS has successfully fulfilled the role of a torchbearer in the Australian industrial electronic equipment market. Check out our products and services, designed to fulfil a wide range of needs. Our experienced and qualified experts are highly equipped to cater to all your industrial electronic needs and offer relevant solutions.
Contact us for more information regarding HUMICAP sensors and their role in humidity and temperature management.
Article courtesy of VAISALA.
