Positional Switch

Positional Switch


a device for closing and opening electric circuits in systems of automatic control by electric drives. A positional switch is actuated by the motion of the mechanism itself. At various points in its travel, the mechanism opens or closes the appropriate contacts of the switch. The operation of the contacts causes signals to actuate the control devices of an automated electric drive.

The simplest and most widely used example of a positional switch in a control circuit is a switch that prevents a mechanism from traveling beyond its normal end position. In this case, the positional switch is called a limit, or end, switch. Positional switches are classified according to their principle of operation as contact (electromechanical) switches and contactless switches, such as induction and capacitance switches.


Komar, M. A. Osnovy elektroprivoda i apparaty upravleniia, 3rd ed. Moscow, 1968.
Ivenskii, Iu. N. Beskontaktnye putevye perekliuchateli v promyshlennoi avtomatike. Moscow, 1971.


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A positional switch sees Israel Dagg move to full-back to take over from Smith, with Naholo stepping into the No.
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But he insisted the positional switch was no sweat having started his career as a winger before playing at full-back, sweeper then in midfield.
Lancaster has made a brave positional switch for the Durban clash by pushing full-back Ben Foden out to the left wing and bringing in Mike Brown at number 15.
SCOTLAND head coach Andy Robinson has made six changes and one positional switch for Saturday's must-win World Cup Pool B clash with England.
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Tait popped up for the try which sent the Lions on their way to a 25-16 victory that day, with the added bonus of Eves' positional switch being the inclusion of semi-final match-winner Tane Tu'ipulotu at outside centre.
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Rees replaces his Cardiff Blues colleague Gareth Cooper in one of four changes and a positional switch following Wales' dramatic 31-24 success against Scotland nine days ago.