×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

DPST NO/NC relay

DPST NO/NC relay

DPST NO/NC relay

(OP)
I need a DPST relay to switch between two signals in the 10 MHz range.  Unfortunately I am not very familiar with relays.  I have found one that is described as such: DPST NO/NC relay and the link to the data sheet is: http://www.clare.com/home/PDFs.nsf/www/Lcc110.pdf/$File/Lcc110.pdf

My question is this: NO/NC means that one input is 'normally open' and the other is 'normally closed'.  So if I apply 5v to the control line, this will activate the NC circuit and deactivate the NO circuit.  So if I apply 0v to the control line is the opposite true?  In other words will the NC circuit now be open and the NO circuit now be closed?  

Also, does this seem like a good relay for the application or is there a better one available?  Thanks.

RE: DPST NO/NC relay

Teledyne make a range of 'proper' relays - not semiconductor switches - which are designed for RF applications:

http://www.teledynerelays.com/

They have a number of products which meet your requirements. A few of their products are available in small quantities from RS Components in the UK.

----------------------------------

If we learn from our mistakes,
I'm getting a great education!

RE: DPST NO/NC relay

If you are trying to "...switch between two signals...", then a Double Pole Single Throw (DPST) relay is probably not the type of relay that you want (assuming that your signals are not balanced - two wire and other complications).

You probably want a Single Pole Double Throw (SPDT) relay to switch one moving contact between two signals.

NC and NO are as you stated.  The word 'Normally' (Open or Closed) means when power is not applied to the coil.

RE: DPST NO/NC relay

Make sure you understand and really do want the latching feature. It is useful for certain applications (saves power), but it can be a unnecessary complication (control wise) if you didn't really want it in the first place.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources