Short-form Snap-action switches - Schaltbau - #4

Glossary :: Snap-action switches

Snap-action switch a switch having a snap-action, micro-gap mechanism which is operated directly by a defined force through a defined travel. The resulting indirect contacting action may be such that the speed of the contacting is independent of the speed of the actuation. [IEV581-10-03]

Positive opening operation an opening operation which, in accordance with specified reguirements, ensures that all the main contacts are in the open position when the actuator is in the position corresponding to the open position of the device [IEV441-16-11],

To ensure the proper working of the positive opening operation it is necessary to depress the plunger to the point of total positive opening travel. However, it must not be sgueezed beyond total travel position.

Utilizationcategories The utilization categories listed in the below table relate to the most freguent applications by which the contact elementscanalsobeclassified:

Contactelements may be classified bythefollowing letters: FormA SPST-NO

Single gap contact element with two terminals. FormB SPST-NC.

Single gap contact element with two terminals. FormX SPST-DB-NO

Double gapcontact element with two terminals. FormY SPST-DB-NC

Double gapcontact element with two terminals. FormC SPDT

Single gap changeover contact element with three terminals.

FormZa SPDT-DB

Double gapchangeover contact element with 4 terminals. The contacts have the same polarity. FormZb SPDT-DB

Double gapchangeover contact element with 4 terminals. The two moving contacts are electrically separated.

Pretravel maximum actuator travel between free position and operating position along which there is no movement of the contactelements

Overtravel path between operating position and total travel position of the actuator after all contactelements have reached their ON/OFF position. To ensure failsafe switching at least 75% of the distance should be covered by the actuator.

Resettravel path between total travel position and release position of the returning actuator along which the snap mechanism has not yet snapped backto itsoriginal position

Free travel path between release position and free position of the returning actuator after the snap mechanism has reverted to itsoriginalposition

Total travel the total of pretravel and overtravel, or reset travel and freetravel

Differential movement the difference between operating positionandreleaseposition

Free position here the actuator is free from any outward applica­tion offorce

Operating position the point along the travel path of the actuator atwhich thesnapactionistriggered

Total travel position the position where the actuator has reached theendofitstravel

Release position the point along the travel path of the returning actuator at which the snap mechanism is released in order to revert toitsnormalposition

Specifications :: Snap-actionswitches

Silver/Gold ©(S80u,S804)

Silver

Silver/Gold

G G

Silver

G G

Enablingswitch

G

² FoWziP¹

² FoTmTb*¹

FormZa ©

G ©

UL94V-0

G G

G

G

.../...

©/-­G

UL94V-0

C

---/---

UL94V-0

UL94V-0

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J

D20.e„

D34.e„

D20.e„

*1 Positive opening operation according to IEC 60947-5-1, annex K

*2 Form Z circuitry SPDT-DB, galvanically isolated

*3 Onlyfor SSOOSeries

*4 In preparation