September / October 2022
Solutions Center: Pyrometers
By Bob Pierce
Q. What is the difference between single-color & two-color (ratio) pyrometers?
A. A single-color pyrometer functions like a camera–if the lens is partially obstructed, the resulting image will be underexposed on the film. When an infrared pyrometer “looks” at an object, it measures the intensity of the radiant energy from the object within its Field-of-View (FOV). So, for a single-color pyrometer, if any of the following happens, it will cause the reading to be inaccurate similar to a camera:
- A partial obstruction in the FOV
- The measured object doesn’t completely fill the FOV
- The IR energy emitted by the object is attenuated by something (e.g. smoke, moisture, dust, etc) constantly or intermittently before it reaches the sensor
Sometimes these things are inevitable–the object does not fill the FOV, an obstruction cannot be moved or the smoke or dust will always be present in the process area which will cause the reading to be incorrect.
A two-color (ratio) pyrometer can usually solve these problems. Some partially obstructed targets (up to 95%) can be accurately measured with a two-color pyrometer. It consists of two single-color detectors in the same package. Using two detector layers, a two-color pyrometer measures the target at two separate wavebands simultaneously. The signals from the two detectors are then processed as a ratio. The calibration curve is based on the ratio of the two signals, which will be very accurate as long as the partial obstruction or attenuation affects each of the wavelengths by an equal amount. If the signal loss in each waveband is the same, then a two-color pyrometer reports an accurate temperature.
Q. Can I look through a quartz window with my 8-14 μm Pyrometer?
A. No. At low temperatures (in the 8-14 μm wavelength range), it is necessary to use a special IR transmissive material such as Germanium, Amtir, or Zinc Selenide. At high temperatures (typically in the 1 um wavelength range), the material most often used is quartz glass.
Q. What wavelength should I use for measuring the temperature of glass?
A. It is recommended to use a sensor with a 5 μm wavelength range for surface temperatures, or 7.9 μm wavelength range for surface temperatures of very thin sheets or low temperatures. Since glass is a poor conductor of heat and can change surface temperature rapidly, a pyrometer with a short response time is recommended. When taking measurements below the surface, a sensor for 1.0, 2.2, or 3.9 μm wavelength should be used.
Q. What is the best single color wavelength for metals and 1200°F or above?
A. The optimal wavelength for high temperatures in the case of metals is at around 0.8 to 1.0 μm. Wavelengths of 1.6, 2.2, and 3.9 μm are also possible. Good results can be achieved using two-color (ratio) pyrometers in cases (e.g. heating processes) where measurement is to take place across a relatively wide temperature range and the emissivity changes with the temperature.
Fluke at NETS
Fluke Process Instruments is the Infrared division of Fluke. Many years ago, Fluke bought Ircon and Raytek, but as those products went obsolete, Fluke replaced them with new ones under the brand Fluke Process Instruments.
The Thermalert 4.0 is the newest in the product line. Offering a variety of wavelengths, it is a single color unit with a max temperature range of 2300 Deg C. It can be used in ambient temperatures up to 85 C. Options include integrated laser sighting, ethernet and analog outputs.
Our flagship offering is the Endurance Infrared Pyrometer. It comes in many wavelengths including 2 colors or ratios. It has through-the-lens sighting, Laser, and video capability. It also has industry-leading optics. It can measure as high as 3200 Deg C. Options include Ethernet IP and Video outputs. For a demonstration please give us a call.
Bags of Hope Christmas Project
As Christmas is on the horizon, our hope at NETS is to give children in Foster Care a gift of significance by coming alongside the “Bags of Hope” Christmas project. Oftentimes children in Foster Care store their personal belongings in a trash bag. It is the goal of Bags of Hope to replace these trash bags with their own personal Duffle bag with their name monogrammed on it and fill it with age appropriate comfort items (i.e. Pillow Pets, journals, fleece blankets, etc…). Bags of Hope has been very instrumental in raising awareness for fostering and adoption, which has led to providing more homes for many children. You can hear how the lives of so many children are impacted by watching the following short video.
Lisa’s Track: ‘Tis The Season, Halloween Through New Years!
As we enter this holiday season, social gatherings filled with food, goodies, and drink surround us like no other time of year. It’s a ‘season’ of celebration, not just a ‘day’ of it. For most, we enter with good intentions and exit it making a New Year’s resolution to pay more attention to our health, lose weight, exercise, meditate, and make more time for ourselves.
You can help yourself by taking small steps and incorporating them into your season for better physical and emotional health. It’s all about balance, moderation, a little planning, and keeping it simple.
Here are a few Tips to help us enjoy the season while keeping your wellness in check:
- Choose a small plate to let you savor the bites while keeping modest portions.
- Eat healthy meals throughout the day so you don’t overindulge… starving yourself during the day so you can indulge at the party that night will BACKFIRE!
- Hydrate: 20 ounces of water, 20 minutes before each meal, keeps you hydrated while reducing cravings and calories when you eat.
- Variety: Balance your plate with a combination of veggies, fruit, and foods of the season…. all in moderation.
- Keep up your exercise routine: Working out keeps your metabolism going, helps you digest and burn off calories, as well as keep anxiety in check.
- Choose lighter alcoholic beverages. A wine spritzer, light beer, or a mixed drink with half a shot in it is a way to keep calories and alcohol content low.
- Look for chances to catch up with friends and family you haven’t seen in a while. Focus more on visiting and catching up rather than over-munching.
- Carve out time to take short walks and for quiet moments to just breathe. The holidays can be an emotional time, filled with sensitive moments and your emotional health is just as important as your physical health.
Remember that the holidays are about ‘spending time’ with relatives and friends. Have a joyful and peaceful holiday season!!!
The Rarest Penguins
By Bree DeLuca
All but one species of penguin live exclusively in the southern hemisphere. The outlier is the Galapagos penguins, which also happens to be the RAREST breed in the whole world!
These interesting flightless birds live right at the Equator on the Galapagos Islands. This is the farthest north of any species, and one of the warmest climates that any penguins in the wild live in! They are one of the only species of penguins who utilize opportunistic breeding which allows them to breed whenever is convenient for them, rather than during specific “seasons” like most other penguins. This allows them to mate when there is more food available since the environment can be unpredictable.
One of the biggest threats to these small penguins is not actually a predator (though they do have those), but the weather. El Nino years in the past have dramatically decreased the populations, and since those times they have struggled to make a comeback. In 1982-83, their population decreased 77%, and then in 1997-98 it decreased another 65% due to the unusually warm waters which deterred their main food sources and made survival a struggle, let alone breeding successfully.
There are an estimated 1200 Galapagos penguins left in the wild, but with the help of some dedicated people who want to see that number increase, some efforts have been made to help them get a step in the right direction. They are a protected species and their main breeding sites are also protected areas, but an even greater help has been a team of researchers building shady artificial nest sites to replace the natural ones that were destroyed by weather.
The penguins in the colder climates tend to make their nests right in the open since they don’t have predators and their bodies are designed for the cold, but since the Galapagos Islands are much, much warmer than the arctic, these penguins have to find shady, cooler spots to nest and protect their eggs, such as small caves and caverns. Having people create more of these has allowed them to be more successful for breeding, and based on the continued monitoring of the nests and population, the researchers have determined that these nests have “accounted for up to 43% of penguin breeding activity”.
Hopefully with the help of dedicated teams like that one, the population of the rarest penguins in the world will start to finally increase!