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CONTACTOR USED TO CONTROL IN INDUSTRIAL

Contactor is an electromagnetic switch used to control any devise in industrila like electrical motors, lighting, heater, or other heavy load. 

figure 1(contactors in spiral mixer)
in operating system of contactor, it is devided in two parts: 
---power contactor (PC): PC is the contact used power circuit, switch on or off electrical motor/lighting/heater/etc. Usually, a power contactor has 3 main contacts which shown figure 2 below. 
---auxiliary contactor (AC): AC is used  the contact used in control circuit, switch on off control system. Usually, auxiliary contact is consist of Normally Open (NO) and Normally Close (NC).


 figure 2 (https://www.etman.no/)

Part of contactor has special tagging according to IEC: 
A1, A2    : is contacts of coil contactor

1, 3, 5      : is supply contacts in power circuit
2, 4, 5      : is load contacts in power circuit

13 & 14   : nomally open contacts (NO)
23 & 24   : nomally open contacts (NO)
33 & 34   : nomally open contacts (NO)
43 & 44   : nomally open contacts (NO)
53 & 54   : nomally open contacts (NO)
63 & 64   : nomally open contacts (NO)
73 & 74   : nomally open contacts (NO)
83 & 84   : nomally open contacts (NO)
93 & 94   : nomally open contacts (NO)

11 & 12   : normally close contacts (NC)
21 & 22   : normally close contacts (NC)
31 & 32   : normally close contacts (NC)
41 & 42   : normally close contacts (NC)
51 & 52   : normally close contacts (NC)
61 & 62   : normally close contacts (NC)
71 & 72   : normally close contacts (NC)
81 & 82   : normally close contacts (NC)
91 & 92   : normally close contacts (NC)

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