The document discusses electromechanical relays. It begins by explaining that electromechanical relays are operated by mechanical forces generated by electromagnetic or electrothermal forces created by input quantities. It then shows a basic diagram of a relay's components: a spring, moveable armature, electromagnet, moveable contact, and stationary contact. The spring keeps the contacts separated until the electromagnet is energized, pulling the contacts together. Advantages of electromechanical relays include their ability to switch AC or DC, low initial cost, and high resistance to voltage transients. Limitations are contact wear over time, short life with rapid or high switching loads, and poor performance with high inrush currents.

1. NORTHERN INDIA
ENGINEERING COLLEGE
PRESENTATION ON
ELECTROMECHANICAL
REALYS
SUBMITTED BY:-
MANOJ KUMAR
13715604914
EEE(1ST
SHIFT)

2. BASICRELAYDAIGRAM
Electromechanical
Relays

3. Principle Of Electromechanical Relay
Spring
To Control Circuit
Moveable Armature
Moveable Contact
Load
Power Supply
Electromagnet
• It is operated by mechanical
forces generated on moving
parts due to electromagnetic or
electro thermic forces created
by input quantities.
• The operation of contact
arrangement is used for
relaying the operated condition
to desired circuit in order to
achieve the required function.
Stationary Contact

4. Electromechanical Relays : What’s Inside
• This diagram shows the
basic parts of an
electromechanical relay: a
spring, moveable armature,
electromagnet, moveable
contact, and stationary
contact. The spring keeps
the two contacts separated
until the electromagnet is
energized, pulling the two
contacts together.
Moveable Armature
Moveable Contact
ElectromagnetSpring
Stationary Contact

5. Electromechanical Relay Advantages
Contacts can switch AC or DC
Low initial cost
Very low contact voltage drop, thus no heat sink is
required
High resistance to voltage transients
No Off-State leakage current through open contacts

6. Electromechanical Relay Limitations
The contacts wear and thus have limited life
depending on loads
Short contact life when used for rapid switching
applications or high loads
Poor performance when switching high inrush
currents
Package Size

7. THANKS FOR YOUR ATTENTION