When a voltage is applied to the coil, a current passes through it and this creates a magnetic circuit which includes the core, armature and the yoke.
The core attracts the armature, which pivots and presses the push rod against the common contact, breaking the electrical connection with one contact and making the electrical connection with the other contact. When the voltage is removed from the coil the magnetic attraction of the armature to the core ceases.
A spring then returns the contacts, pushrod and armature to the initial position. In this example, the common contact also acts as the spring, but in other relays, a separate spring is employed.
The above animation shows that when we apply a voltage to the relay coil, the Relay contacts will change.
For example the Normally Open (NO) becomes Normally Closed (NC) and similarly the Normally Closed (NC ) becomes Normally Open (NO). When we remove the applied voltage to the relay coil then the relay contacts again comes into default state.
Design a relay (CR1) circuit which controls two lamps, one is Red lamp (R) and another is Green Lamp (G). These lamps will be controlled by using a single switch (S).
When switch is pressed then Red lamp will be ON and Green lamp will be ON during switch de-energised state.
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Dear sir I need help in configuration of pid loops in Siemens s7 200 smart PLC using microwin software
Great engineering imformation. I have a question about relay schematic: when switch is pressed: Are NO relay CR1-1 has good symbol?