testsubject
Member
I currently use a Safety module from Wieland and have been asked to use a GuardLogix PLC.
I have two outputs setup in the controller to output Safety Ch A and B.
I then connect these signals two safety relays with the contacts wired in series from 24VDC to the Common terminal of a standard PLC output card. (Safety Switched 24VDC)
These safety relays are disabled by the Estop when pressed. When this happens, the 24VDC is removed from the output card and they can no longer operate the valves.
Now that I am using a GuardLogix PLC, I am wondering if I am monitor the Estops in the GuardLogix PLC and this information can be passed through to the standard code, is this sufficient to satisfy the safety protocol or do I still need to use the two external relays to block the 24VDC? (I am wondering if the Signal in the Safety Side of the PLC could be used as a permissive in the Control Side outputs.)
I have two outputs setup in the controller to output Safety Ch A and B.
I then connect these signals two safety relays with the contacts wired in series from 24VDC to the Common terminal of a standard PLC output card. (Safety Switched 24VDC)
These safety relays are disabled by the Estop when pressed. When this happens, the 24VDC is removed from the output card and they can no longer operate the valves.
Now that I am using a GuardLogix PLC, I am wondering if I am monitor the Estops in the GuardLogix PLC and this information can be passed through to the standard code, is this sufficient to satisfy the safety protocol or do I still need to use the two external relays to block the 24VDC? (I am wondering if the Signal in the Safety Side of the PLC could be used as a permissive in the Control Side outputs.)