Part number : 3TF50
Function : Contactors for Hoisting Duty
Manufacturer : Siemens ( www.siemens.com )
AC-2 operation is the typical duty for starting and switching off fully-loaded slipring motors in the starting phase. The rating of the contactor, to switch the motors, is selected primarily on the basis of rated make & break capacity and desired electrical endurance.
Selection and ordering data
Benefits and features
1. Long life
(1) “Hoisting Duty “Contactors are provided with new design of contacts (AgSnO2 instead of AgCdO) resulting in high electrical and mechanical life.
(2) They are electrically superior in taking care of excessive stresses coming on contactors during their operations in crane applications.
(1) The “Hoisting Duty” Contactors have vacuum impregnated coils which are suitable for high frequency switching and high vibrations. This helps in reducing coil failures.
(2) Side mounted auxiliary contact blocks are screw mounted and not snap fitted to withstand vibrations and high frequency operation.
Reference PDF : 3TF50.PDF