Crap, Enttec just burned out

jediknight2

Full time elf
Joined
Aug 30, 2012
Messages
196
Location
North Carolina
It was raining outside and while my show isn't going on tonight my power came on to the show. So I walked in the garage to turn everything off and smelled an electric burning smell.....Ended up being my Enttec OpenDMX device. Its got a chip that burned up. So my question is how did this happen and how much damage could it have done. I plugged my DMX 10W RGB floods back in and they all go into the automatic color cycle. Since they are doing that I HOPE they didn't get zapped. Second thing is....what can cause this? My connection out to the lights leaves my computer using DMX+ and DMX-, no ground from the OpenDMX controller.....The chip is the one at the bottom center...

http://i.imgur.com/RlqVxBU.jpg

I should also add that only one of my power supplies were plugged in to the lights. The one on down the line used to inject wasn't plugged in..but I doubt just a reduced amount of power would do that...I would just loose color control at the end. I have 5 Ray Wu 10W RGB floods
 

riri7707

Full time elf
Joined
May 9, 2010
Messages
222
Location
Paris / France
Unfortunatelly, this happens often when some wrong voltages or ground feedback on the RS422/485 chain (DMX ).
You can just replace it by an SN75176 or MAX 487. In most of the boards, this chip was on socket and not soldered due to replacement purposes.
The cost of this component is less than $1.
If urgent, check the ref on your board if still present and go to www.mouser.com.
 

fasteddy

I have C.L.A.P
Global moderator
Joined
Apr 26, 2010
Messages
6,648
Location
Albion Park NSW
Some additional data regarding this. It is raining

So maybe +v is shorting across to the DMX line due to water ingress or causing ground loops to be created

Do you have 12vdc lights
 

jediknight2

Full time elf
Joined
Aug 30, 2012
Messages
196
Location
North Carolina
Just went out and did a continuity test on the line. I put one end of the multimeter on DMX+ and touched it to the opposite end that goes into the controller. I get a tone. I then placed the prong on the positive voltage on one end and the DMX+ end that goes into the controller....nothing.

I have 4 boxes hooked up and going to my computer
I have a 12VDC PS hooked to some pixels that are connected to a ECG-P2 connected to my computer
I have a Renard48LSD running on 12V daisy chained to a Renard SS24 connected to a USB.
The OpenDMX which got fried.

Everything is plugged into one 6 outlet timer plugged into one outlet. NOW..my computer is plugged into a different outlet controlled by a different breaker.
 

riri7707

Full time elf
Joined
May 9, 2010
Messages
222
Location
Paris / France
Disconnect you Enttec device and replace the burned driver.
Don't insist here as regarding your circuit, you can dammage also your ftdi chip.
fyi, the input of the data is on PIN 4 of the burned chip comming directly for your FTDI chip, it can be dammaged also, depending how the driver was burned inside. It's a crap than most of the manufacturers didn't use automattically an optocoupler behind the driver to protect the line (production costs)...
So no choice here as first step, repair or replace your DMX device...
At the same time, something must to be wrong in your DMX line ( can be rain, humidity, moisture on connections, etc...)
The rain PB creating periodic shorcuts and not permanent are quite hard to find. you need to control all chain connection.
 

jediknight2

Full time elf
Joined
Aug 30, 2012
Messages
196
Location
North Carolina
I am going to order another DMX controller and toss this one as it looks like more trouble than its worth to fix. I will call Enttec tomorrow just out of curiosity for repair. I will also go through every connection before applying power back. It is possible that something is poking through some shrink wrap. The only direct water ingress I have is at the end of the line, That was taped up and when I took the tape off it was bone dry. I am using 4 prong pigtails so everything SHOULD be water tight. I will unwrap everything though and add a piece of tape over every heat shrink solder just for extra measure......I just hope I didn't fry every one of my floods...too late to get something from Ray now.
 

riri7707

Full time elf
Joined
May 9, 2010
Messages
222
Location
Paris / France
The logic wants you have a problem on your DMX line only due to a major issue in one of your DMX device.
For the pixels, etc... They are under management of other circuits/outputs logic with drivers protected normally by a fuse in your third party devices. Means if you have a shot circuit somewhere on your lights chain, one output canl be faulty and normally cannot affect your main dial through DMX devices and the full display.
Here I suspect more one of your DMX devices, other than the Enttec as source of the problem.
Check this point first
 

David_AVD

Grandpa Elf
Community project designer
Generous elf
Joined
Jun 12, 2010
Messages
4,681
Location
Victoria Point (Brisbane)
This is why I made our USB-485 converters with isolation. You can still damage a 485 chip, but at least you won't fry your PC.
 

David_AVD

Grandpa Elf
Community project designer
Generous elf
Joined
Jun 12, 2010
Messages
4,681
Location
Victoria Point (Brisbane)
jediknight2 said:
question...had i been using a e6804 to control the dmx data here....would it have just blown a fuse?

Most likely the result would have been a dead E6804 board, or at least the 485 chip on it.
 

jediknight2

Full time elf
Joined
Aug 30, 2012
Messages
196
Location
North Carolina
Yeah, Jim said I would have most likely fried pin one on the CPU. I did ask Enttec about it and they said it was one of three things...

1.Lighting strike or weather even near by which caused a voltage spike directly on the data line, basically the wiring acting as an antenna on the ground

2.Accidental misdirection of voltage onto the data line, ie short or even an induction loop (didn't think about that one)

3.Ground Loop, which I don't really understand enough to know if this could be the cause
 

jediknight2

Full time elf
Joined
Aug 30, 2012
Messages
196
Location
North Carolina
This is going to sound silly. .. but how could I test for voltage on the dmx data lines. ..I only have dmx+ and dmx- at the computer. .. can I use the ground on my pixel power supply. ..my dmx devices are powered outside at the first flood
 
Top