The most important point to understand
about the relay is that the electrical circuit that energizes the coil is not connected electrically with the contacts.
Electromechanical Relay
The contacts are moved by a magnetic
force, so they are electrically isolated from the coil voltage.
Electromechanical Relay
NORMAL STATE
When the relay coil is activated,
All NO contact will close,
All NC contact will open.
How Relays Work.
A relay has basically 4 parts :
• An electromagnet.
• A spring.
• An armature attracted by an electromagnet.
• Electrical contacts that act as a switches.
PB1 Activated
Closed -> LHS
Direct Circuit (NO push button)
PB1 not Activated
NC -> RHS
L1 - Pilot Light / Indicator Light
Inverse Circuit (NC push button)
PB1 Activated
Open -> RHS
Inverse Circuit (NC push button)
Three phase motor control
DC Motor
Stepper Motor
Induction Motor
