IEN: What innovations are in store for environmental sensing technology?
Phillips: In general, you will see a trend toward smaller-sized, lower power temperature and humidity sensors in battery-powered dataloggers. It''s important to note that while these sensors will be smaller and lower power, they will be every bit as accurate as sensors the industry has relied on in the past.
Users will also see more in the way of convenient data retrieval solutions. For example, here at Onset we offer customers a number of options to offload data. Customers can use our HOBO data shuttle, which is a handheld device that can offload and store data from a number of dataloggers, and then be taken back to an office PC where the data can be graphed and analyzed. We also offer Palm-based data offload solutions and remote communications. No matter what a customer chooses to use, the end goal is the same: to make the data retrieval process faster and easier.
Another area of innovation is in systems-based dataloggers. While standalone dataloggers are suitable for a broad range of applications, there may be situations where you need more of a centralized data gathering mechanism for measuring a number of parameters. For this reason, Onset now offers systems-based dataloggers based on "smart sensor" technology. This means that you can simply plug in individual sensors to measure various parameters and the system recognizes each one without complicated wiring, programming, or calibration. These datalogger systems are also battery powered, and allow you to configure the system with any combination of available sensors.
IEN: What are some of the newer application areas for industrial environmental sensing/datalogging?
Phillips: We are seeing a lot of interest in using battery-powered dataloggers for energy management applications. For example, people want to use loggers for energy audits, so they can gain a good understand of building processes and understand when power is being used. The goal here is usually to decrease their peak load and learn when power is being used unnecessarily, such as when lights are left on in unoccupied spaces.
We also see dataloggers being used in more and more mold investigation applications. There is a great deal of awareness about sick building syndrome, and the ability to continuously record humidity levels in facilities, whether they are office buildings or elementary schools, is becoming more and more important.
IEN: How do today''s dataloggers differ from more traditional, PC-based data acquisition systems?
Phillips: PC-based data acquisition systems, which frequently require the installation of additional circuit boards and controls in the PC as well as the external wiring of cables and sensors, work well in permanently configured, online applications. However, they can be expensive and difficult to implement, especially in situations where short-term monitoring is required. Dataloggers, in contrast, are easy to deploy, because they require no extra wiring and are standalone devices, and can be placed in areas that other permanently configured systems cannot reach. They can also be easily removed and reused for other applications as needed, thereby significantly reducing the price-per-channel for most logging applications. And, dataloggers typically require very little maintenance, and offer long-term battery operation for remote sites.
IEN: What should potential users of dataloggers / environmental sensing products know about measurement accuracy?
Phillips: No matter what you need to measure, job one is understanding your measurement accuracy requirements. For example, if you''re monitoring air conditioning temperature in an office space, you may only need temperature measurement accuracy of +/- 2 degrees, whereas monitoring conditions in a research lab may require accuracy that is much greater.
Accuracy specs vary widely among different types of dataloggers, and we find that a good understanding of specific accuracy requirements upfront will help you avoid paying for accuracy that you may not need. When looking at the accuracy specifications for a given datalogger, be sure to look for charts that indicate accuracy over an entire measurement range, not just a single value. The accuracy a datalogger can achieve at the high or low end of a given range may be far different from the accuracy at the middle of the range.
Another important factor is datalogger resolution, which basically refers to the number of increments of a value a datalogger is capable of reporting. For example, a datalogger with 12-bit resolution can report 4,096 values over a given temperature range. While a 12-bit datalogger may offer more resolution than an 8-bit model, it''s important to point out that higher resolution does not necessarily mean better measurements.