UM2 Left fan always on?

[apex1001 0]

Hello people of the UM forum,

I am new here but not new at 3D printing. And I have a question you might be able to answer:

I've been using my Ultimaker2 for a year now with mixed results. Quality is not as good as I think it could be and I have warping issues with ABS, probably connected to temperature/cooling. While searching for ways to improve my prints I came across 3DVERKSTAN's guide to better prints via the Ultimaker support page. An interesting read.. However..

At about 2/3 of the article it is stated that the CENTER fan at the back should always come on as soon as the printer is turned on. But with my ultimaker2 the LEFT fan always comes on as soon as I turn on the printer. The center and right fan can be controlled via the menu or via the Tweak at Z plugin. The left fan cannot be controlled and is always at the same speed.

Is this normal behaviour? Or is it a wiring error? If 3DVERKSTAN's guide is right I might have to do some rewiring on my UM2. If so, what's the best way to do this? Can I simply switch some connectors around or do I need to take out the old soldering iron :-).

Best regards,

Vincent

 

[Dim3nsioneer 557]

It's definitively a wrong wiring. You may correct it yourself; shouldn't be too difficult.

It's rather interesting that your hotend survived that long...

[IRobertI 517]

Yup, incorrectly wired for sure. Not sure how they managed that though... The side fans are wired in series to the plugs with green/green and green/yellow wires. The middle fan goes to the orange/blue connector.

 

[apex1001 0]

Okay, I disassembled the printhead to find the correct wires for the fans. It turns out the center and left fan wires had been switched. I was able to remedy this by switching the 2p connectors in the wiring loom. However the cable lengths are not quite correct (center fan cable is 3 cm too short, left one too long) which leaves me to believe they are cut to size on assembly of the printhead. After that a 2p connector is crimped on. If you mistakingly switch the cables on cutting you get exactly what I had. But all seems ok.

I do find it a little bit odd this made it through quality control. The problem is quite apparent when you switch the printer on.

The hot end seems to work fine still. Everything is working as intended, but now I have to go and find out the best ABS temperature/cooling settings all over again .. For now 50% fan seems to work best.. Before it was 15% fan ;-),

Thanx for the help!

Vincent