M77/M78 Two Color Transmitter

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M77/78 2-color Infrared Temperature Transmitters Innovative Design The M77/78 series “Infraducers” represent a milestone in infrared temperature measurement technology. They are the first commercially available, completely self-contained, 2-color radiometers to produce a 4-20mA linear output. The “Infraducers” represent the latest in innovative technology, integrating exclusive advanced electronic design with optical and mechanical precision that are the essence of Mikron infrared products. Their design from concept to finish is based on simplicity of installation and maintenance. The M77/78 series, with its matchless array of accessories, demonstrates Mikron’s continuing leadership in infrared temperature measuring technology. Why 2-color Infrared Thermometry? The M77/78 series are “state of the art” instruments designed for the measurement of temperatures above 250°C (500°F). They utilize the 2-color principle, in which the temperature measurement is made by ratioing the radiation intensities of two adjacent wavelengths rather than from absolute intensity as with single band (or single color) instruments. This design approach eliminates a number of factors that degrade the accuracy of conventional instruments. For example, temperature measurements with the M77/78 are: • Independent of emissivity • Unaffected by dust and other contaminants in the field of view • Independent of target size (can produce accurate reading with only 5% of the target area within field of view) • Unaffected by moving target within field of view • Unaffected by dirty viewing windows point of failure in other instruments. Also, there are no optical or electronic adjustments to be made in the field. An invalid signal LED warns if the target radiation intensity drops to a level too low for reliable measurements. The M77S Sensor Head incorporates a high quality, high precision variable focus optical system that provides sharp focussing on the desired target from about 2” (50mm) to infinity. Focussing is executed by turning the focussing knob on the rear panel of the instrument. The M77S enables precision pinpointing of small target areas. The user simply adjusts the instrument until the desired target is clear within a reticle. M77LS for Laboratory & Research Applications The M77LS was specifically designed for research and laboratory applications and is readily adaptable for either tripod or optical bench use. Its through-lens sighting and variable focussing features permit precision pinpointing of the target area. M78 for Inaccessible or Environmentally Severe Applications The fiber optics based M78 “Infraducer” is recommended for areas where the following conditions exist: A. When direct sighting with the M77S is impossible due to obstructions. The flexibility of the fiber optics cable overcomes this problem. B. Where RF or EMI interference is a problem, requiring the electronics to be placed at a safe distance from the source of interference. C. Where exceptionally high ambient temperatures exist. Fiber optic tips and lens assemblies can withstand temperatures up to 600°F (315°C) without cooling and up to 1000°F (540°C) with air cooling. D. Where corrosive environments prohibit the use of a conventional system. E. In vacuum applications where sighting through the window is difficult or impossible, a fiber optics lens assembly can be placed inside the vacuum vessel. F. When an intrinsically safe IR temperature transmitter is mandatory. G. Environments where nuclear radiation is present. A specially designed lens and fiber optics assembly can withstand high nuclear radiation levels. M77LS Laboratory Version Mikron 77/77S for Industrial Applications The M77 is housed in a compact, rugged stainless steel housing only 8” (200mm) long and 2” (50mm) in diameter. Superior design not only insures accuracy and long term reliability, it also guarantees interchangeability between “Infraducers” of the same model with ±0.75% accuracy. This ensures that, should one of the “Infraducers” need to be replaced, the replacement unit would be as accurate as the original unit. The M77 has absolutely no moving parts which are often the VISUAL SIGHTING RETICLE DEFINES EXACT AREA OF TEMPERATURE MEASUREMENT INVALID READING EYEPIECE QUICK DISCONNECT CONNECTOR M77LS REAR PANEL SLOPE ADJUST FOCUS 2
How to Select an M77 Sensor Head Since there are three M77 models (M77, M77S, M77LS) as described on the previous page, it is first necessary to determine which model you require: a. M77 – Fixed focus b. M77S – Variable focus, see through lens c. M77LS – Variable focus, see through lens for laboratory and research applications. After choosing the desired model follow these 4 steps. 1. Select the temperature range and units (C or F) from ranges listed. Insert ranges and units in Box 1 , filling in all blanks with zeros. 2. Place letter “R” or “R1” in Box 2 for standard spectral response. 3. Select signal output; (L) for standard 4-20mA linear, or (U) for others and insert in Box 3 . 4. Select the correct operating distance. a. If you selected the M77 fixed focus model, specify the desired focus distance in writing (See Table 1.) and enter “U” in Box 4 . b. If you selected the focussable M77S or M77LS read the section “Optical Resolution” below. Then choose the desired operating distance and insert the corresponding Code No. in Box 4 . EXAMPLE The model chosen for the instrument indicated in the selection chart is the focussable M77S with through lens sighting for a temperature range of 800° to 1800°C with spectral response of two narrow bands, with 4-20mA linear output and a focussable operating distance of 350mm (14”) to infinity. Optical Resolution Three different lenses are available for the M77S. The one you should choose depends on the desired working distance of the unit. The first version is designed to measure temperature at distances of 350mm (14”) to infinity. The second version has a working area of 150mm (6”) to 350mm (14”). The third version is fixed to measure temperatures at a 50mm (2”) distance. Proper focussing is achieved by mounting the unit at the desired distance and adjusting the focussing knob on the rear panel of the instrument until the target comes into clear view in the reticle. When the target is in focus to the eye, it is also in focus to the detector. Should you wish to move the instrument, remember to stay within the prescribed working distance, and simply refocus upon the target after mounting the instrument in its new location. A typical field of view diagram is shown below. Minimum Target size determined by the formula: Minimum Target Size (d) = TARGET SIZE (d) Focussed Distance (D) Field of View Ratio DISTANCE (D) Example: M77S, version 1 with 30:1 FOV focussed at 381mm (15”) D 381 Minimum Target Size(d) = = = 12.7mm FOV 30 15” (or = = 0.5”) 30 Selection Chart M77S 0 8 0 0 – 1 8 0 0 C R L 3 1 1 TEMPERATURE RANGE 3 FIELD OF VIEW RATIO °C °F 350-800 660-1500 550-1200 1025-2200 15:1 600-1400 1100-2500 400-1000 750-1800 650-1400 1200-2500 30:1 450-1200 850-2200 700-1400 1300-2500 700-1700 1300-3100 700-2000 1300-3600 800-1800 1500-3300 60:1 800-2300 1500-4100 900-1600 1800-3200 500-1400 950-2550 1000-2500 1800-4500 1000-3000 1800-5400 1100-2200 2000-4000 90:1 1200-3200 2200-5800 1200-3500 2200-6500 Notes: 1. Special temperature ranges are available upon request. 2. See table 1 for availability of focus distances for FOV selection. 3. Some 90:1 FOV temperature ranges are also available with a 180:1 FOV. Please consult Mikron. TABLE 1 – M77 MINIMUM TARGET Field of Fixed Focus View No Sighting Ratio 15:1 D/15 30:1 D/30 60:1 D/60 90:1 D/90 180:1 D/180 Consult Mikron MINIMUM FOCUS DISTANCE 2” 2” 6” 6” 14” Table 2 – M77S, M77LS Minimum target sizes are shown in the table below Field of Version 1 Version 2 Version 3 View Focus 14” Focus 6” Focus at Ratio to Infinity to 14” 2” 15:1 23.6mm (0.93”) 10.2mm (0.40”) 3.3mm (0.13”) at 350mm (14”) at 150mm (6”) at 50mm (2”) 30:1 12mm (0.47”) 5mm (0.20”) 1.5mm (0.06”) at 350mm (14”) at 150mm (6”) at 50mm (2”) 60:1 6mm (0.24”) 2.5mm (0.10”) at 350mm (14”) at 150mm (6”) N/A 90:1 4mm (0.16”) 1.8mm (0.07”) at 350mm (14”) at 150mm (6”) N/A 2 2 SPECTRAL RESPONSE CODE R1 R R1 R R1 TWO NARROW BANDS R NEAR INFRARED R1 OUTPUT 4-20mA Linear CODE L 1 3 4 4 OPERATING DISTANCE (See note 2) CODE 350mm (14”) to 1 infinity 150mm (6”) to 350mm (14”) 50mm (2”) fixed How to Select an M78 Sensor Head The selection process for the M78 is similar to that of the M77, with the additional requirements of the fiber optic feature. The selection steps are as follows: 1. Select the temperature range and units (C or F) from ranges listed. Insert ranges and units in Box 1 , filling in all blanks with zeros. 2. Place letter “R” or “R1” in Box 2 for standard spectral response. 3. Select signal output; (L) for standard 4-20mA linear, or (U) for others and insert in Box 3 . 4. Select the length of fiber optics cable and insert code number in Box 4 . 5. Select the required lens assembly from the field of view diagrams and insert code number in Box 5 . If, however, an extension tip is to be used, the code number inserted in Box 5 should be selected from the chart under Rigid Extension Tip; both stainless steel and ceramic tips are available. 2 3
Page 1: 2-Color Non-Contact Infrared Temper
Page 5 and 6: How to Select an M77E/77EM Electron
Page 7 and 8: Support Electronics — A Complete

M77/M78 Two Color Transmitter

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