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Just like the title says. Can I run 3 5v fans in series in 12v?

I was at a local electronic component supply shop the other day. And they had some little 25mm 5v fans that output 4cfm. They were only $3/ea so I bought a handful. The idea was to use 3 of them in series to cool the print using the Rambo. I know I could just hook them up to a 5v line from the PSU, but I want more than a bang-bang control with them.

Thanks

In theory it should work fine, certainly wont damage them trying.

I'm sure it would be fine at 100% fan speed, but you might have issues at low speeds (just a guess).

Maybe it's worth running them in parallel with a resistor for each instead?

The cheap little motors that run fans won't care about the 7V difference. I have taken a few of these apart, the wire is the same wire that is used in 12V dvd motors.