Rockwell Automation 871TM Extended Range User Manual - Manual

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871TM Extended Range
Inductive Proximity Sensors
User Manual
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UMMARY The Extended Range 871TM all stainless steel family of inductive proximity sensors offers sensing
ranges 2x--3x those of standard inductive models. In addition to providing equal sensing distance for
mild steel and aluminum, the 871TM Extended Range also senses other metals at ranges greater
than standard technologies. Although extended sensing range technology allows for improved
performance, certain additional installation/application considerations must be taken into account.
T
ARGET
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ONSIDERATIONS Material :
Unlike standard proximity sensors which offer considerably less sensing distance for nonferrous
metals, Extended Range 871TM proximity sensors detect such materials at distances almost equal
to that of steel. See the correction factor chart below for the most common target materials:
Correction Factors
:
Note : Correction factor data based on standard target sizes (IEC 60947--5--2 / 8.3.2.1.1)
Barrel Diameter Steel FE 360 Copper Aluminum Brass
Stainless Steel
1mm Thick
Stainless Steel
2mm Thick
Shielded M12 1.0 0.85 1.0 1.3 0.45 0.9
Unshielded M12 1.0 0.8 1.0 1.3 0.5 0.9
Shielded M18 1.0 0.85 1.0 1.3 0.4 0.8
Unshielded M18 1.0 0.85 1.0 1.3 0.1 0.8
Shielded M30 1.0 0.9 1.0 1.2 0.5 0.9
Unshielded M30 1.0 0.85 1.0 1.2 no detection 0.5
Note :Stainless Steel targets are the exception; sensing distances for stainless steel are dependent on target
size, thickness and grade.
Target Thickness :
The sensing behavior of conventional inductive proximity sensors is only slightly influenced by the
thickness of the target, foils being the one exception. Generally aluminum foil will produce a higher
sensing range than thicker metals. 871TM Extended Range units however, behave differently. The
sensing distance for metals over approximately 1mm thick remains constant for most materials
(stainless steel excluded) used in machine construction. However, for targets less than 1mm thick
the sensing range decreases and foils, in general, cannot be detected.