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Member
Posts: 302
Registered: ‎01-04-2012
Kudos: 120
Solutions: 11
Accepted Solution

12v output stuck on?

After burning out 2 Mports and 1 doorbell solenoid, I figured its time to ask for help. 

I have a gate chime wired up to know when someone opens our gate to the back yard. Originally it was a "crap! little ones are making a break for it!" Now its "Hey, who just went in the backyard?" 

I have it set to activate 12VDC output for 1 second on port 3. After 1 second it turns off until the gate is closed, and at that time when the gate is reopened the chime is activated by another 1 second burst. Originally it worked as designed for 2-3 years. 

Original mfi, the system stopped working and we started smelling burning plastic. turns out the mechanical solenoid on the doorbell was held open so long it melted the plastic housing. 

Replaced the doorbell and shortly afterward the mport stopped responding. 

This new mpower has been working fine for other uses, but I havent had the doorbell plugged in while I waited to add a one shot timer to prevent the burnout. (timer circuit activates, then turns off the device automatically after 1 minute. When power is pulled, the timer resets)

I started testing the original system as built. I went into the console and turned power on in the gui, and the doorbell chimed. I turned off the power in the gui and the virtual switch toggled to off. A few minutes later my 10yo walked by the doorbell and said "Hey dad, whats that buzzing?" Sure enough, the output was still live, contrary to what the controller said the output was.

Any ideas? If I activate the 12v output on port3, it doesnt turn off until I power cycle the mport. (And the mport might go inactive and/or reboot after the power is active too long, not sure.)

I even deleted the object in the controller and recreated it. 


Accepted Solutions
Member
Posts: 302
Registered: ‎01-04-2012
Kudos: 120
Solutions: 11

Re: 12v output stuck on?

[ Edited ]

I may have figured it out. Too much current draw on the controller port does it. 

If I dont plug in the doorbell, it works fine. I can activate and deactivate the output just fine. 

If I plug the doorbell in, the excess current draw seems to hold the power open. Even after I disconnect the doorbell, it stays energized regardless of what the gui says it is doing. It will hold that output voltage until I power cycle the mport. 

Looks like its time for plan b: activate a relay and use a separate power supply for the bell. 

View solution in original post


All Replies
Member
Posts: 302
Registered: ‎01-04-2012
Kudos: 120
Solutions: 11

Re: 12v output stuck on?

[ Edited ]

I may have figured it out. Too much current draw on the controller port does it. 

If I dont plug in the doorbell, it works fine. I can activate and deactivate the output just fine. 

If I plug the doorbell in, the excess current draw seems to hold the power open. Even after I disconnect the doorbell, it stays energized regardless of what the gui says it is doing. It will hold that output voltage until I power cycle the mport. 

Looks like its time for plan b: activate a relay and use a separate power supply for the bell. 

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