Posted 4 Nov 2020 Hi, I have a modicon premium plc rack with TSX PSY 3610 power supply module. The psy 3610 power supply has an alarm contact and it is used in a loop to energize a hard ware relay for 24VDC supply to the DO module FTA boards. There is a safety button in parallel to the alarm contact so that during startup we can press this button, energies DO module loops and all IO faults cleared and power supply alarm contact latches The problem is that this power supply alarm contact remains always open even when IO report no faults. The PLC has MAST task only and it is running with no faults. If I jumper the alarm contact all the IO's are healthy . tried changing the power supply and DO modules. no hope. please help. Share this post Link to post Share on other sites
Posted 9 Nov 2020 Maybe you should test Power Supply that have problem with other CPU to check that problem from Power Supply or CPU? Share this post Link to post Share on other sites
