Chosing time relay

Hello experts,

I have one rather newbie situation and need to choose appropriate time relay. I need the following functionality:
- when timer relay's coil is energized, its contact (NO) is closed immediately and stays closed 10 sec (or time t)
- when 10 sec is elapsed contact opens.
- if coil is deenergized, it opens immediately.

The time diagram is shown in the attachment. I need your recommendation about the time relay needed for this purpose.

Thank you!

So if the [timer relay's coil] is energized beyond the 10s, then the contact not immediately close again, is that correct (that is what your timing diagram seems to show)?


You may want one of the circuits here:


http://www.contactandcoil.com/patterns-of-ladder-logic-programming/


You may have

• Your initial signal
• Timer.EN for when the timer input (rung) is true
• Timer.DN for when the timer is done (complete)

You may also have

• Timer.TT for when the timer is timing (accumulating time) but not yet done
  • Timer.TT := Timer.EN AND (NOT Timer.DN)

Look at the Eaton ETR4 multifunction timers

Hello guys, thank you for the replies.
Contact is instantly closed when relay coil is energized, and contacts remain closed for 10 sec, after the time = 10s elapse, contact is open again no matter if the coil remains energized. When coil is deenergized, contacts open. As soon as coil is energized again the contacts close and remain for another 10 sec.

I needed basically just what I found in the document moggie suggested.

Thank you.

That is referred to (over here anyway) as a "One Shot Timer". Most timer manufacturers offer them, either as single function devices or as an option in multi-function timers. No idea what you have access to in Albania, but Siemens is available pretty much everywhere. Their 3RP25 series timers can do this.

jraef said:

That is referred to (over here anyway) as a "One Shot Timer". Most timer manufacturers offer them, either as single function devices or as an option in multi-function timers. No idea what you have access to in Albania, but Siemens is available pretty much everywhere. Their 3RP25 series timers can do this.

Click to expand...

Thank you very much. I'll go with the Siemens' relay.

For a great reference of timer functions, check out the Appendix on this catalog:
http://stevenengineering.com/tech_support/PDFs/40MAIN.pdf

SSAC was once the the greatest manufacturer of timers, but after being bought and sold several times, there's not much left (now Littelfuse). BUT, the knowledge lives on!