<https://community.ultimaker.com/topic/9159-what-fans-to-install-on-umo/#comment-103563>
<http://schema.org/text>
"It is definitely the input voltage, so 24V in this case. \n(The UM2 is using 2 12V fans in series) \n  "
<https://community.ultimaker.com/topic/9159-what-fans-to-install-on-umo/?tab=comments#comment-103299>