Thermal Cutout - better approach, other devices?

Thread Starter


Joined Sep 24, 2013
Attachment shows a Selco disc thermostat, manual reset, opens at 250F, 125VAC, 15A, in a circuit intended to completely shut down a 3d printer if the build plate overheats.

Need small size (this tstat is 1/2" dia.), mountable to bottom of plate, manual reset, 120VAC, preferred >15A. Less than $10-15.

Is there a better approach? I searched for a small 20A rated manual reset disc tstat, but couldn't find one.
Are there other devices that could be surface attached to the bottom of the plate?

Any comments/help appreciated. Thanks.
printer  thrm cutoff.jpg


Joined Aug 1, 2013
Snap-disc (Klixon) thermostats have always worked well for me, as long as I don't need precision control. If +/- 5 or 10 degrees is good enough and you just need to switch more power, I'd suggest using the snap-disc to control a relay with a greater contact rating but you already have a relay. You can put the thermo disc in the control side of the relay, but that won't help if the relay fails shorted.