After a mega effort, we have moved our Hamilton office to new digs at 9 Kells Pl, Frankton, Hamilton.
This gives us a bit more flexibility with the range of projects we are involved with and has a donut shop just round the corner. It is not far from the old place: Kells Pl runs off Duke St, which runs off Greenwood St (part of the SH1 Hamilton bypass)
FOCUS ON TEMPERATURE MEASUREMENT
Temperature is one of the most commonly measured parameters, whether it be from measuring the comfort level in your own home to mapping long term climate change. There is an extremely wide range of sensors available to measure temperature depending on the medium, accuracies and ranges. Here are a few products and applications, some common, and some which push to the extremes:
Most people know that to make accurate air temperatire measurements you need to use a radiation shield. This prevents the sensor body itself from heating up and reading high. In most cases a passive shield is sufficient, however where higher accuracy is required, or in areas of low air flow, an active shield, where a fan increases air flow past the sensor, is required. Once of the more challenging environments for accurate air temperature measurement is over snow pack. A study by Apogee in mountainous Utah, showed that in one week near the time of peak snowpack, a six-plate passive shield matched the active TS-100 shield within 0.2°C at night, and within 0.5°C when conditions were overcast and windy, but differences on sunny days with moderate wind were often 2-3°C and as high as 7°C with low wind. The TS-100 is a low power aspirated shield that will improve temperature measurements during low wind conditions (<4m/s) for any application.
While for some winter brings the chance to enjoy the slopes, others are lying awake, worrying that frost will destroy their crops. In addition to our Frost Alert or alarming weather stations using a standard air temperature sensor, we can offer Apogee's radiative frost sensor. This mimics the form and surface of both a leaf and a bud. They have found that under low wind radiative frost conditions, the temperature reading of this sensor can be up to 4°C lower than that of the temperature in a radiation shield, giving a much more accurate picture of the actual frost risk.
While we prefer to be warmer, many products that we depend on require storage in stable and chilled conditions. From vaccine fridges in doctors surgeries to container loads of produce (or even fertilised chicken eggs) travelling overseas.
For real-time monitoring, we recently built a system to monitor a number of chillers and freezers for a mushroom grower. These need careful temperature control and are connected through ethernet, with data displayed on the web. Graphs clearly show if the temperature is within limits and indicates activities such doors opening and shutting.
If real time monitoring is not required, HOBO have a range of low cost temperature monitoring devices that can be downloaded to PC or Mac.
People, plants and animals all have critical and comfortable temperatures for life and growth.
In horticulture seed will not germinate until the soil reaches a certain temperature. This means that farmers and growers have been monitoring soil temperature for as long as it's been possible. In later years, air temperature is increasingly used to calculate Growing Degree Days, Potential Evapotranspiration and pest specific disease models. Scottech have developed a range of standard stations suitable for growers that will integrate with providers such as HortPlus.
Some of our users have gone further than just measuring temperature and used the control functions of a Campbell Scientific logger to control greenhouse ventilation, to improve growing conditions and extending the growing season for economic advantage. These controlling dataloggers range from the 5-input CR200X to the newest CR6 (pictured) complete with USB & MicroSD. They can be configured to turn pumps and motors on and off based on any measured value.
For specialised horticulture and energy research there are a range of tools to measure temperature or heat flux in difficult environments. Here's a small selection:
Apogee's range of infrared sensors are used to measure the surface temperature of leaves or other surfaces. This makes it suitable where a contact sensor is not possible.
Whether human or fish we all have our ideal comfort temperatures.
Aquatic fish species are particularly susceptible to changes in water temperature meaning that this is one of the key water quality parameters monitored. The HOBO TidbiT has long been the datalogger of choice for ecological researchers and monitoring bodies due to it's robustness and reliability. This has been added to with the U22 and Pendant low cost loggers.
If you're a human, you are more likely to use one of the HOBO range of indoor dataloggers designed to monitor rooms for comfort and energy use. The UX100 series measures temperature & humidity, with a display and is used extensively in museums and archives. The new MX1101 (pictured) adds the functionality of Bluetooth download to a smart phone.
Sometimes the operation of a system is a life or death matter. One of our customers is using a Campbell based system to verify the sterilisation system used in a number of hospitals. The system monitors an electrochemical process which treats the hot water against Legionnaires disease. A Campbell Scientific CR200X datalogger monitors 4-20mA signals as well as hot water temperature, with data available remotely via web page. This is completely independent of other hospital network systems and provides peace of mind to users that all is working as it should.
For other monitoring around boiling point, the HOBO U12 logger is used in autoclaves, or steam cooking.
For seriously hot applications, finding a sensor that will both measure and survive can be a challenge. One customer wanted to monitor the temperature of a geyser as a way to work out it's eruption pattern. We selected a Geokon 3800 sensor which works up to 150°C, with a custom stainless steel housing and Teflon cable, logged by a CR200 datalogger. This worked really well despite some interesting results in temperature swings of 80 deg + during eruptions.
Finally, at the top end of the range, some applications require sensors to measure at very high temperatures. Thermocouples are often used for this, and Scion have purchased a number of these to be logged by the UX120 thermocouple logger to monitor the passing of a vegetation fire front.
