Relay Flashcards
What is a relay?
An electrical control circuit (commonly a memory logic element)
What does a relay do?
What’s an application?
Holds the output powered, after input is removed
Application is powering a power value solenoid, performing a control logic, activating a seal-in
What does a relay have?
A solenoid coil, contacts, and spring (AC/DC require a unique coil)
Powered/depowered?
When powered, shifts contacts to opposite state
When depowered, return contacts to normal state
How is a relay displayed on a ladder diagram?
A circle with 1CR, the solenoid coil for relay
What is a seal-in circuit?
A wiring method causing relay to stay powered after input’s released (important memory logic function)
How do you depower a seal-in?
Depower the coil (by a stop pushbutton)
