CTB16pc KIT U1, HOT transformer

[daniel]

Ok, first off. The u1 chip is blown. That is something that is strange. The controller was working fine, and then today, I plugged it in and the controller did not respond, recalling what had happened when I first built this controller, I took the U1 chip out and the LED started working like it should. But if I remember correctly from before, this is the communications chip, so it still would not work. (U1 chip was getting warm before I took it out)


So thats on my list of things to order from LOR, a few extra u1 chips.



Now, for the big problem...


I put the U1 chip back in, and left the controller unplugged. But apparently I plugged it back with my ctb-16D while testing my mini-director. So both controllers had power unknowingly.


I started smelling melting plastic and heat. I thought that was just a little heat coming off of the ctb-16D, so I ignored it. While checking out something in the ctb-16D, I reached over and placed a hand on the ctb-16pcK. The plastic was very warm. I hit the power switch on the power tap and cracked the case open. and saw the little sticker on the top of the transformer was melted, and heat was radiating out. Now the smell was bad, and I thought thats not very healthy to be breathing, so I took it out and its sitting on the porch right now to chill out.



Now, in a few min Ill bring it back in and examine the controller to see what happened. This is a controller that worked perfectly last week. I am guessing this heat thing is related to the u1 chip going. But after all that heat, I think I will probably send it in to LOR to have a look at it. Ill shoot them am email in the next few days to see what I should do.



--DanieL L

[-klb-]

Was the AC line in plugged in with the bad U1 chip installed? If so, the transformer is converting AC from 120V to a lower voltage that feeds the rectifier and power supplies, which in turn are feeding power into a shorted out U1 chip. So heating the transformer is probably all that is limiting the current going thorough those components. It is probably best to leave out known bad components like U1, just in case power is applied to the unit.

There shouldn't be any way that power can make it back from the control cable in a way that could heat the transformer.

[daniel]

When it heated up the AC was plugged in, U1 was installed, and the Cat-5 com cable was not connected. So the controller was standing alone. Like I said, I thought it was unplugged at the time. I am guessing it was the logic half that had power at the time. And since the LED does not flash with the U1 faulty, I had no visual to see if it had power before I closed the case.


Yea, now that its cooled down enough to handle, Ill take the U1 out till I figure out what to do.

I probably will take the chip out of my ctb-08 and swap it in to see what happens. If that solves it, then I guess all Ill have to do is order another chip. If that goes too, then Ill send it in.



--Daniel L

[aemnky]

I had the same thing happen to me. I sent an email to dan at LOR and he said that the chip some times gets an internal short and sent me a new chip.



Walter

[daniel]

aemnky wrote:

I had the same thing happen to me. I sent an email to dan at LOR and he said that the chip some times gets an internal short and sent me a new chip.

 

Walter

Ok, that is encouraging. Ill do the chip swap tomorrow to see how it goes. If the board comes to life, Ill check everything out to make sure the heat did not damage it. I saw a chip that "may" be fading white from the heat, so not sure if that is damaged any. So Ill be checking it all out very carefully.


--Daniel L

[aemnky]

As far as i could tell my controler did not have any damage and i left mine on for the night thinkin that i unpluged it. So you should be ok.





Walter

[daniel]

aemnky wrote:

As far as i could tell my controler did not have any damage and i left mine on for the night thinkin that i unpluged it.  So you should be ok.

 

 

Walter

Hmm well after the chip swap it did come back up, and it tested out ok. Hmm, not to sure still b/c it looks like the transformer discolored a bit, and it still gives off that melted-plastic oder. Operation-wise it works perfectly though.

I am going to say it is fixed, ignore the smell and just see what happens next. I will be using 2-3 channels of this controller to control some lamps and such with my mini-director. So It will have a nice long test before Christmas use comes along.


Ill shot LOR an email tonight ordering a few chips, one to replace the one I took out of my ctb-08 and a couple extras to have incase this happens again. While I am paying for shipping now, I think I am going to request the new firmware chip for the ctb-08. Might as well...



--Daniel L