M77/M78 Two Color Transmitter
M77/M78 Two Color Transmitter
M77/M78 Two Color Transmitter
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<strong>M77</strong>/78 2-color Infrared Temperature <strong>Transmitter</strong>s<br />
Innovative Design<br />
The <strong>M77</strong>/78 series “Infraducers”<br />
represent a milestone in infrared<br />
temperature measurement technology.<br />
They are the first commercially<br />
available, completely self-contained,<br />
2-color radiometers to produce a<br />
4-20mA linear output. The “Infraducers”<br />
represent the latest in<br />
innovative technology, integrating<br />
exclusive advanced electronic design<br />
with optical and mechanical<br />
precision that are the essence of<br />
Mikron infrared products. Their<br />
design from concept to finish is<br />
based on simplicity of installation<br />
and maintenance. The <strong>M77</strong>/78<br />
series, with its matchless array of<br />
accessories, demonstrates Mikron’s<br />
continuing leadership in infrared<br />
temperature measuring technology.<br />
Why 2-color<br />
Infrared Thermometry?<br />
The <strong>M77</strong>/78 series are “state of the<br />
art” instruments designed for the<br />
measurement of temperatures above<br />
250°C (500°F). They utilize the<br />
2-color principle, in which the temperature<br />
measurement is made by<br />
ratioing the radiation intensities of<br />
two adjacent wavelengths rather<br />
than from absolute intensity as with<br />
single band (or single color) instruments.<br />
This design approach<br />
eliminates a number of factors that<br />
degrade the accuracy of conventional<br />
instruments. For example,<br />
temperature measurements with<br />
the <strong>M77</strong>/78 are:<br />
• Independent of emissivity<br />
• Unaffected by dust and other<br />
contaminants in the field of view<br />
• Independent of target size (can<br />
produce accurate reading with<br />
only 5% of the target area<br />
within field of view)<br />
• Unaffected by moving target<br />
within field of view<br />
• Unaffected by dirty viewing<br />
windows<br />
point of failure in other instruments.<br />
Also, there are no optical<br />
or electronic adjustments to be<br />
made in the field. An invalid signal<br />
LED warns if the target radiation<br />
intensity drops to a level too low<br />
for reliable measurements.<br />
The <strong>M77</strong>S Sensor Head incorporates<br />
a high quality, high precision<br />
variable focus optical system that<br />
provides sharp focussing on the<br />
desired target from about 2” (50mm)<br />
to infinity. Focussing is executed by<br />
turning the focussing knob on the<br />
rear panel of the instrument.<br />
The <strong>M77</strong>S enables precision<br />
pinpointing of small target areas.<br />
The user simply adjusts the instrument<br />
until the desired target is<br />
clear within a reticle.<br />
<strong>M77</strong>LS for Laboratory<br />
& Research Applications<br />
The <strong>M77</strong>LS was specifically designed<br />
for research and laboratory<br />
applications and is readily adaptable<br />
for either tripod or optical<br />
bench use. Its through-lens sighting<br />
and variable focussing features<br />
permit precision pinpointing of the<br />
target area.<br />
<strong>M78</strong> for Inaccessible or<br />
Environmentally Severe<br />
Applications<br />
The fiber optics based <strong>M78</strong><br />
“Infraducer” is recommended for<br />
areas where the following conditions<br />
exist:<br />
A. When direct sighting with the<br />
<strong>M77</strong>S is impossible due to<br />
obstructions. The flexibility<br />
of the fiber optics cable overcomes<br />
this problem.<br />
B. Where RF or EMI interference<br />
is a problem, requiring the<br />
electronics to be placed at a<br />
safe distance from the source<br />
of interference.<br />
C. Where exceptionally high ambient<br />
temperatures exist. Fiber optic<br />
tips and lens assemblies can<br />
withstand temperatures up to<br />
600°F (315°C) without cooling<br />
and up to 1000°F (540°C) with<br />
air cooling.<br />
D. Where corrosive environments<br />
prohibit the use of a conventional<br />
system.<br />
E. In vacuum applications where<br />
sighting through the window<br />
is difficult or impossible, a<br />
fiber optics lens assembly can<br />
be placed inside the vacuum<br />
vessel.<br />
F. When an intrinsically safe IR<br />
temperature transmitter is<br />
mandatory.<br />
G. Environments where nuclear<br />
radiation is present. A<br />
specially designed lens and<br />
fiber optics assembly can withstand<br />
high nuclear radiation<br />
levels.<br />
<strong>M77</strong>LS Laboratory Version<br />
Mikron 77/77S<br />
for Industrial Applications<br />
The <strong>M77</strong> is housed in a compact,<br />
rugged stainless steel housing only<br />
8” (200mm) long and 2” (50mm) in<br />
diameter. Superior design not only<br />
insures accuracy and long term<br />
reliability, it also guarantees interchangeability<br />
between “Infraducers”<br />
of the same model with ±0.75%<br />
accuracy. This ensures that, should<br />
one of the “Infraducers” need to<br />
be replaced, the replacement unit<br />
would be as accurate as the original<br />
unit. The <strong>M77</strong> has absolutely no<br />
moving parts which are often the<br />
VISUAL SIGHTING<br />
RETICLE DEFINES<br />
EXACT AREA OF<br />
TEMPERATURE<br />
MEASUREMENT<br />
INVALID<br />
READING<br />
EYEPIECE<br />
QUICK<br />
DISCONNECT<br />
CONNECTOR<br />
<strong>M77</strong>LS<br />
REAR<br />
PANEL<br />
SLOPE<br />
ADJUST<br />
FOCUS<br />
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