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UM2 rear 5V fan


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Posted · UM2 rear 5V fan

I'm fitting a UM fan kit (ULT1004000327-P1) to an Ultimaker 2. The new 2x 12V side fans are working fine, but when I plugged the rear 5V fan in, at first it wouldn't work, then spun normally for a while, then finally when I tested it before reassembly it started to smoke and now doesn't work.


When I check the polarity of the feed from the FAN 5V J34 connector on the PCB it's reversed compared to the red/black colouring of the cable in the wiring loom. I've attached a photo of the plug on the PCB end of the wiring loom (top) compared to the plug on the fan (bottom).


The old fan obviously worked fine, and has the same serial number as the new one, so I need to know if the wiring is correct, or has the loom been made up wrongly when assembled originally. Also whether the new fan I fitted doesn't like the polarity being reversed or was just faulty.


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    Posted · UM2 rear 5V fan

    Hey Mari, thank you very much for this. I learned some handy stuff from the manual, especially the bit about aligning the bearings, but sadly it doesn't mention the polarity of the fan DC supply, although it does point out which way the rear fan should be facing, which suggests that the direction it spins in is important. Thank you.

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    Posted · UM2 rear 5V fan

    Another reference is the assembly manual

    https://github.com/Ultimaker/Ultimaker2/blob/master/um2 assembly manual V1.1 _english.pdf


    and the mainboard schematics:

    https://github.com/Ultimaker/Ultimaker2/blob/master/1091_Main_board_v2.1.1_(x1)/Main Board V2.1.1.pdf



    As fas as i can see the 5V cable inside the wiring loom should be pink (ground)  and blue (+5V) - assembly manual page 65

    There are pictures of the 5V fan and its connector as well (page 51)


    Hope that helps!


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