Shop Learn
Relay Library Symbol Standard — Parallax Forums

Relay Library Symbol Standard

bradsawhaoldbradsawhaold Posts: 1
edited 2021-11-16 07:31 in General Discussion

I don’t often use relays in my projects but I was investigating a simple circuit that required a relay. At this point any DPDT relay would do.

My surprise and questions is:
It seems all the relays in the standard library are drawn in what appears to be the “energized coil” position. I had always drawn relays in the unenergized position where the moveable relay element was furthest away from the coil.
I also see the “contact” point on the stationary contacts have a filled or not filled configuration. From a standards view I’m not aware of the meaning of such a graphic.

Is there some recent standard for drawing a relay in such a manner?


  • I’m not following your question. What library are you referencing?

  • MicksterMickster Posts: 1,923

    Contacts are referred to as Normally Open (NO) and Normally Closed (NC)

    "Normal" = coil not energized.

    The standard that I am accustomed to is that; terminals that include a "3" and a "4" are always NO and those that include a "1" and a "2" are NC:

    11 and 12 = NC
    13 and 14 = NO

  • evanhevanh Posts: 12,021

    Swap the 1 for the 14 and have the lever leaning the other way would satisfy both.

    Of course, a solenoid can also be built to pull in either direction but, like Brad, my first instinct is to imagine it pulling the leaver toward itself.

Sign In or Register to comment.