Did I kill my DuetWiFi?



  • Hello!

    So I was measuring the voltages on the Duex5, as I wanted to attach a raspberry (5V) and a LED (12V) on my 24V system in order to avoid too many more power supplies.

    Picture of shorted pins

    Than i slipped and accidentally short circuted thos two pins on the duex.
    Webcontrol is offline and the powersupply, which only runs the fan when it re requiring juice, is powering up.

    I suppose I killed the Duet as it also appears to work this way when the duex is not attached.

    Please help.



  • see
    https://duet3d.dozuki.com/Wiki/How_to_destroy_your_Duet_2

    you feed 12 into the 5v.

    which of the leds on the duet board for the voltage 3.3 5 vin turn on?



  • LEDs

    If I get this correctly, following LEDs are on:
    LED E1 HEAT
    LED E0 HEAT
    LED VIN
    LED +5V

    ...and

    LED 3.3V

    is off.



  • OK, its pretty straight forward in the "How to kill your Duet"
    link text

    "Short +3.3V to +12V or +24V. This is quite tricky to achieve if you want to make it look like an accident. However, if you are using a 3.3V Z probe such as the mini IR sensor, then you have a 3.3V power wire going to the hot end. So you could 'accidentally' mis-wire your hot end to swap a heater or fan wire with the 3.3V supply to the Z probe, and hey presto you have fed 12V or 24V into the 3.3V power rail. Several devices run from 3.3V including the SAM4 processor and the WiFi module."

    However, I had the impression I only shorted 12V to 24V on those two pins. Any thoughts on that?



  • looks like you might have done 5v to 12/24v, so with a bit of luck you can replace the 5v regulator or even provide external 5v if the 3.3v side of things are still okay.



  • you arrows go to 12v and 5v.

    that picture is very hard to see and the 3.3v one is behind the wire.

    check
    https://github.com/T3P3/Duet/blob/master/Duet2/Duet2v1.04/DuetWifi_Schematic_v1.04.pdf

    for the component label u2 and see if that is damaged on your board.


  • administrators

    If you shorted 12V to 5V, it will have blown the 3.3v regulator which is only rated at about 6.5V input.

    I suggest you apply USB power and see what parts get hot. Check the SD card, WiFi module, 3.3V regulator, main processor, and U11 in particular. At least those components that get hot will need to be replaced, possibly more.



  • @Veti V3.3 is behind the wire, but it is off.

    Connercted to the computer it does not find the Duet's USB port.

    I am afraid, this amounts to much more fixing than I intend to do.

    Thank you for your feedback, I will get back to it when I have more time, but for now I regard it as destroyed.

    @dc42 I did that on the duex, so did I fry the duex as well, or do you think it possible that the duex stayed intact?

    Regards,
    Konrad


  • administrators

    @Deltasquare said in Did I kill my DuetWiFi?:

    @Veti V3.3 is behind the wire, but it is off.

    Connercted to the computer it does not find the Duet's USB port.

    I am afraid, this amounts to much more fixing than I intend to do.

    Thank you for your feedback, I will get back to it when I have more time, but for now I regard it as destroyed.

    @dc42 I did that on the duex, so did I fry the duex as well, or do you think it possible that the duex stayed intact?

    Regards,
    Konrad

    It depends on how high the +3.3V rail got before something blew and effectively shorted it to ground. The SX1509B chip may well have failed. If you are unlucky, all 10 stepper driver chips may have failed too.

    If you have SMD desoldering equipment then I suggest you remove the SD card and try applying +3.3V to the +3.3V rail. Or if you prefer, apply 5V power via USB, but then you may need to replace the 3.3V regulator chip before you can get anywhere. Identify which components are getting hot, remove them, and try again. When no components are getting hot with 3.3V applied, fit the Erase jumper and see if you can get the Bossa port to appear on a PC connected via USB.

    FWIW you are not the first person to short +5V to +12V. This is why I decided to remove the 5V fan jumper position on Duet 3.



  • So I have a new board now. Just to make sure this time:

    If I run a 24V System, I can only set the voltage to 12V on the DueX.
    For this purpose we have the jumper on the Duex. If I set it I can power Fans as well as LEDs from Duex, however, the Duex does not act as a constant power source for the LEDs.

    Please verify.


  • administrators

    @Deltasquare said in Did I kill my DuetWiFi?:

    So I have a new board now. Just to make sure this time:

    If I run a 24V System, I can only set the voltage to 12V on the DueX.

    By "I can only set the voltage to 12V on the DueX", do you mean you can set the Fan voltage to 12V on the DueX but not on the Duet? If so, that is correct.

    For this purpose we have the jumper on the Duex. If I set it I can power Fans as well as LEDs from Duex

    Correct, if you connect the LEDs to spare fan outputs.

    however, the Duex does not act as a constant power source for the LEDs.

    Do you mean that you want some "Always-on" LEDs? The most recent DueX5 revision has a 12V always-on output (when the 12V Enable jumper is in place). For other DueX5 revisions, with the fan voltage selection jumper set to 12V you can connect a 12V always-on fan or LED between the VFAN pin of any fan output and the ground VIN connection.