3D Printing Forum

Or buy some fans and get Amedee to draw a nice Arduino UNO sketch and a breadboard layout to test PWM

I ordered these: http://www.ebay.nl/itm/-/301473854304?
and soldered them red to red, black to black (series is this?)
Don't know much about electronics but it works.
Made an aluminum bent shroud for it, protecting the nozzle from the wind flow. For me this was more importent then directing the airflow. And the choice for metal instead of a plastic shroud.

Yes, and about the same power specifications as the Delta fans I have been looking at

Yes in series...did yours come with the connector? Or solder into the existing?

No, red on red and black on black is parallel!

I think I will make a picture...

LePaul wrote:None of the support places I've seen stock UMO fans. Just UMO+ on up

Neotko wrote:And what about a stepup from 19v to 24v? This way you could use the easy-to-find sunon 50x50x10 umo+ fan on your umo. It's easy to do a stepup?

I don't think it is necessary, the difference in not that big.
And you are replacing a single one by 2, so total flow will be higher anyway.

Also I have seen in the Sunon specs that they have Slow/Normal/Fast version, so if you take a 'Fast' one, that should be good (don't know what the original is though )

Here the picture:

I think we might have a breakthrough here...

I eventually found a well known Asian site advertising UMO fans. You never know what you eventually get, but one buyer says:

perfect replacement for the Ultimaker original fan. Same size, voltage and all.

From the picture I eventually deciphered the part number: FSY50S12H.
More info here

I am happy to order some for testing, but you need to be patient, it typically take 15 to 20 working days to get things from Asia delivered here (the worse part being our local custom who need more than a week to clear € 5 items...)

I see this (based on that search) from Amazon...

http://www.amazon.com/uxcell%C2%AE-FSY5 ... B00OK8QTIK

always get confused with the series/paralel thing....., thanks for the explanation!
I choose smaller fans because I could shift them both a little out of the center, so the left one is a little to the front and the right a little to the back.
So the air would not 'clash' in the middle. Nothing calculated, nothing tested, just rational thinking, and I am happy with the setup.

I'm not sure if the connector for the fan is the same on the UMO as the UM2 but I managed to obtain the pits for the connector as below.
JST XHP-2 Female housing #4552266ND
XH22-28 AWG crimp #45511351ND
From www.proto-pic.co.uk
I used these parts to put a connector on my rear heatsink fan replacement. Preferring to use a connector than anything else.

um2 umo+ uses a molex... umm searching on my order list

They sold it to me as "Molex Jumper 2 Wire Assembly" I got a bunch from a portugal company, all assembled ready to solder to a pair of cables.
http://www.inmotion.pt/en/cables/811-mo ... embly.html

The crimp machines for this connectors, as well as the motor ones, are waaaaay expensive.

Btw LePaul, with a thin plier, you can, pressing down the connector, take our the metal that connects inside the molex, remove the soldering and reuse it as many times you want, unless you break the metal thingy, but they are really hard under normal conditions.

Watch out, there are many types of Molex connectors. Make sure you get the right one!

"Actual" PWM fans always have 4 wires. VCC (red), GND (black), RPM signal (usually yellow), PWM input (blue afaik, but could be different).
The PWM input goes into a transistor inside the fan that properly implements PWM control. That also means that the PWM signal does not carry any current.
RPM signal should be left unconnected (unless you want to read out the actual fan RPM). This is an open-collector output, so you could put it on a microcontroller pin and add a pull-up resistor to the controller's VDD in order to read it. NEVER connect this wire to the fan's VCC (V+), that would create a nice short-circuit and probably kill something in the fan's circuitry.

3-wire fans are always VCC (red), GND (black), RPM signal (usually yellow). The wires can also be uni-color. These aren't "actual" PWM fans.

2-wire fans only have the power wires. No RPM signal and no PWM input.


All that doesn't mean that you can't PWM-control the fans through their VCC pin (red). This works with most fans, and pretty much any PC fan is controlled this way (except for the main CPU-fan which should be a 4-pin).
However - this kind of PWM control is not as simple as the reprap devs want it to be. So, it will probably work for many fans, but it won't work for some and could also shorten the lifespan of some fans considerably.
The best you can do is try a fan and see if it works...

Lot's of good information but I am stuck wondering which fan to order

The Fonsoning FSY50S12H I mentioned yesterday is a working replacement fan for the UMO.

Now we can continue to discuss for ages on voltage, current, fan size, fan shrouds.. and do our best to confuse you

But I think this is the answer to your initial question...