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EZIO8SA fails to update ISY994 Current State on some digital inputs


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Hi Guys, first time poster here. I have been using digital input 1 (DI1) on the EZIO8SA as part of my ISY994i system for about a year without any trouble. Now I am adding a second input.  Adding DI2,3 and 4 has stumped me, however. I am using dry contacts from motion sensors connected to the digital inputs to turn on lights via Z Wave dimmers - so, the faster the better!  For testing purposes, I have connected a binary thumbwheel switch to the 4 inputs and confirmed that I have voltage present at each optocoupler at the appropriate position. 

Input 1 works every time.

Input 2 seems to work most times and

Input 3 fails most times. 

Input 4 fails most times

If I Query the network manually through the Administrative Console, the "Current  State" changes to display all 4 inputs correctly.


Any help would be appreciated.


Thanks, David




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Hi Michel,


I have attached an image of the connections that I made to the EZIO8SA via TB1.


Inputs 2-4 are not shorted.


I have not been exposed to the event viewer until now.  I wired up test switches to inputs 1-4 and found out a few interesting things via the event viewer.  


1. If I turn the switches on in the same sequence as my actual application - everything works as expected.

2. If I turn the switches on in any sequence leaving a time delay between switch changes, everything works as expected

3. If I turn multiple switches on simultaneously, one or more current states are not updated correctly.

4. The contact bounce created by my interposing relay (as measured across DI3 in my actual application and seen on one of the attachments) appears to cause problems

5. When the current state is not updated correctly, the communication information regarding a change of state of that input does not exist in the event viewer


 I'll let you know how this turns out







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SOLVED: turns out that failure to update was being caused by contact bounce.  I have eliminated the contact bounce by replacing the mechanical relay with a solid state relay (see attachment for scope results)


Michel, Thanks for pointing me to the Event Viewer.




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