Now let s go through a real world example of normally open and normally closed contacts that we are all familiar with.
Normally open contactor wiring diagram.
The may be 2 or more sets of output contacts identified.
2 days ago i wired 380 to 440 volts contactor for a 3 phase motor and save these images of contactor in pc.
Relays and contactors have two types of contacts each suited for different applications.
Programmable unijunction transistor scr.
Generac smm wiring diagram to breaker panel to water heater line neutral 120 volts ac one to four 50 to 225 amp normally open contactors installation and wiring with the new generac smart a c module installation wiring with the 240 volt coil no contactor 65 100 amp compatibility guarantee.
Lighting contactors 6 1 open control catalog number selection type c30cn lighting contactors c 3 0 c n m 2 2 a a 2a 0 product c30cn open 30a lighting contactor class e electrically held m mechanically held mechanically held control module voltage a0 110 120 vac h0 200 277 vac t0 24 vac t1 24 vdc number of normally closed poles.
Its is important to.
For instance the following diagram shows a normally open pushbutton switch controlling a lamp on a 120 volt ac circuit the hot and neutral poles of the ac power source labeled l1 and l2 respectively.
Normally open no contacts allow current when the relay or contactor is energized.
Note that one one of the contactor acts as a switch for the start button.
A simple circuit diagram either of the two start buttons will close the contactor either of the stop buttons will open the contactor.
In other words when voltage is applied to the relay contactor terminals this contact closes.
Normally closed nc contacts allow current through when the relay or contactor is not energized.
Unijunction transistor table 1 standard elementary diagram symbols cont d battery bell annunciator buzzer horn alarm siren etc.
These contacts may be indicated on the label as normally open no and normally closed nc.
Contactor wiring and i hope after this post you will be able to wire a 3 phase motor i also published a post about 3 phase motor wiring with magnetic contactor and thermal overload relay but today post and contactor wiring diagram is too simple and easy to learn.
Rarely are these familiar examples good for learning but a 3 way switch is an excellent example of using normally open and normally closed switches.
Subscribe a simple breakdown of how a normally open switch no should operate vs how a normally closed switch nc should operate when wired correctly.
Study the contactor manufacturer information.