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Heat Pads for Animal Hospital

Raven Luni

Oct 15, 2011
798
Joined
Oct 15, 2011
Messages
798
Greetings,

This is more or less how the final thing will look. I have a couple of redundant fault triggers. The protection circuit is designed to prevent overheating rather than protect the actual circuit - the only thing that matters is that the poor animals dont burn to death.

A second thermistor set slightly higher by the 5K pot will trigger a fault in the case that the main one fails or becomes detatched somehow. When the heater is turned on, the 470uF capacitor starts charging until the transistor triggers a fault after about 10 seconds (the heater should have reached its set temperature and be turning on and off before this time).

Most contingencies should be covered except those that would prevent heating. In this case a competent carer monitoring things should notice, but all the dangerous conditions should be covered.

therm1.png
 
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