enter image description here

Here is a SIL3 Relay: SCS 24 V DC P2SIL3ES(made by Weidmuller). In its manual, It's written that S11,S12 and S21,S22 connections will provide a monitoring circuit for this relay. But I can't understand how? can any body help me understand Its operation?

Here is the link to the it's manual: https://www.dropbox.com/s/x3k37ad6lalw1tp/1438130000_00_03.13_MAN_SCS_24VDC_P2SIL3ES_EN.pdf?dl=0

  • \$\begingroup\$ Thats not a link to the datasheet. At the very least you could attach a screenshot of it to your question so that later when that site changes and your instructions are invalidated someone can read the question and knows what it is about too. \$\endgroup\$ – PlasmaHH Jun 14 '17 at 11:20
  • \$\begingroup\$ @PlasmaHH yes you are right. Here I added the link to the manual. \$\endgroup\$ – MINA ASHTIANI Jun 14 '17 at 11:34
  • 1
    \$\begingroup\$ You asked pretty much the same question, electronics.stackexchange.com/questions/285812/…, on 2017-02-11 and accepted the answer and thanked the author. Why are you asking again? \$\endgroup\$ – Transistor Jun 14 '17 at 11:39
  • 1
    \$\begingroup\$ @Transistor here in this type, there is something different. the question you mentioned is about a sil3 relay with testing function and my question was about how it can test the cantacts and it was solved. but here, in this product, I can't understand how the monitoring fucntion works. \$\endgroup\$ – MINA ASHTIANI Jun 14 '17 at 11:46
  • 1
    \$\begingroup\$ The 'Monitor' in a SIL relay is normally a pulse train output on Sx1. Sx2 want's to see the exact, in phase Sx1 pulse train to be considered closed. If the contacts open, degrade, or if someone directly ties Sx2 to +24V, the safety outputs open. Also, ALL input channels must activated at the same time, as channel 1 and 2 are timed to probably under 100 ms for closures. Anything different, and the relay faults open. \$\endgroup\$ – R Drast Jun 14 '17 at 14:04

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.