4/21/2023 0 Comments Temperature fan controllerThe MOSFET is directly controlled by the NTC thermistor. It's clever in several ways - read the referenced text to find out why. You can easily make it a sort-of PI controller This simple but clever circuit is a P controller :-) ( P for Proportional). You did not say why - and you MAY have meant that you did not want to pay the usual price for one - ie a cheap PIC controller or similar may be OK. You said you wanted to avoid using a PID controller. It provides "hysteresis" which controls how much diffetrence there is between fan stop and fan start temperatures. They are non critical as long as you understand how they work and can adjust as required. P1, R1, P2 could all be larger with increased voltage. A say 12V zener so Vgate - ground ~=12 V would be OK. IF you use the 24V for op amp supply and FET you'd need a zener on the FET gate to limit gate drive. Here is a direct fan drive circuit that is otherwise similar. That circuit is from here but they stole it from somewhere else to get people to look at heir ads so ignore them. As you have not told us the fan power or current rating we can't be sure about the transistor. This use a relay to turn the fan on and off but you could connect it in the transistor collector if the transistor was suitable. This shows a 12V fan but 24V would work equally well. BUT it may not, as we don't yet know exactly what you want. This circuit looks like it would do exactly what you want.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |