Hi
I am needing some advice on how to wire a 3 phase fail relay into an Allen bradley input card. And also what line of logic should I use to bring in an alrm when the relay switches.
The situation is: I have a mains power supply that is linked to a back up UPS, if mains power is lost. The relay has been wired up so that if the mains power is lost and we go over to the UPS, the relay switches over from being NC to NO, this triggers an alram on a SCADA screen notifying an operator. How do you wire the 3 wires to the AB Input card? The 3 wires are: A Normally open, a normally closed and a common.Also how would you write the line of logic to make sure when the mains power is on and working the relay is ok (NC), but when mains power is lost, the relay switches to being NO and an alarm is activated. I can set up the alarm ok. Its just knowing what initial line of ladder i need to write.
Many Thanks
I am needing some advice on how to wire a 3 phase fail relay into an Allen bradley input card. And also what line of logic should I use to bring in an alrm when the relay switches.
The situation is: I have a mains power supply that is linked to a back up UPS, if mains power is lost. The relay has been wired up so that if the mains power is lost and we go over to the UPS, the relay switches over from being NC to NO, this triggers an alram on a SCADA screen notifying an operator. How do you wire the 3 wires to the AB Input card? The 3 wires are: A Normally open, a normally closed and a common.Also how would you write the line of logic to make sure when the mains power is on and working the relay is ok (NC), but when mains power is lost, the relay switches to being NO and an alarm is activated. I can set up the alarm ok. Its just knowing what initial line of ladder i need to write.
Many Thanks