Brochure

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Limit switches
OsiSense XC
General
Presentation
Electromechanical detection
Limit switches are used in all automated installations and also in a wide variety of applications,
due to the numerous advantages inherent to their technology.
They transmit data to the logic processing system regarding:
v presence/absence,
v passing,
v positioning,
v end of travel.
Simplicity of installation, advantages
b From an electrical viewpoint
v galvanic separation of circuits,
v models suitable for low power switching combined with good electrical durability,
v very good short-circuit withstand in coordination with appropriate fuses,
v total immunity to electromagnetic interference,
v high rated operational voltage.
b From a mechanical viewpoint
v NC contacts with positive opening operation,
v high resistance to the different ambient conditions encountered in industry (standard tests
and specic tests under laboratory conditions),
v high repeat accuracy, up to 0.01 mm on the tripping points.
Detection movements
b Linear movement (plunger) b Rotary movement (lever) b Multi-directional movement
Terminology
Rated value of a quantity b This replaces the term “nominal value”.
b It is the xed value for a specic function.
Utilisation categories: b AC-15 replaces AC-11: control of an electromagnet on AC,
test 10 le/le.
b AC-12: control of a resistive load on AC or static load isolated
by opto-coupler.
b DC-13 replaces DC-11: control of an electromagnet on DC,
test le/le.
Positive opening travel b Minimum travel from the initial movement of contact actuator to
the position required to accomplish positive opening operation.
Positive opening force b The force required on the contact actuator to accomplish
positive opening operation.
Switching capacity b Ithe is no longer a rated value but a conventional current used
for heating tests.
Example: for category A300 the corresponding operational
current, le maximum, is 6 A-120 V or 3 A-240 V, the equivalent Ithe
being 10 A.
Positive opening operation b A limit switch complies to this specication when all the closed
contact elements of the switch can be changed, with certainty,
to the open position (no exible link between the moving
contacts and the operator of the switch, to which an actuating
force is applied).
b All limit switches incorporating either a slow break contact
block or a snap action NC + NO (form Zb), NC + NO + NO,
NC + NC + NO, NC + NC + NO + NO contact block are positive
opening operation, in complete conformity with standard
IEC 60947-5-1 Appendix K.
Presentation,
terminology
TrippedUnactuated
TrippedUnactuated
Tripped
Unactuated