namezero111111
New Member
Hello eletronic folks,
I am a hobbyist trying to build a thermostat that both heats and cools. I have come as far as having the circuit built, but what happens is that once the relay coil switches on, it causes a voltage drop in the whole circuit, so when the temperature change is very gradual the relay switched on and off multiple times before staying on. I have tried putting capacitors between the transistor and relay so soften that effect, but it still occurs.
The problem, I believe, is that the transistor doesn't switch enough power when the IC turns high. I tried adding another transistor in series with the first one (NPN switching PNP transistor) but that just created smoke
I'm confused as to how to give this setup a better "snap"...
I have attached a picture of the circuit diagram and hope you can help me. Thank you so much!
-Andy
I am a hobbyist trying to build a thermostat that both heats and cools. I have come as far as having the circuit built, but what happens is that once the relay coil switches on, it causes a voltage drop in the whole circuit, so when the temperature change is very gradual the relay switched on and off multiple times before staying on. I have tried putting capacitors between the transistor and relay so soften that effect, but it still occurs.
The problem, I believe, is that the transistor doesn't switch enough power when the IC turns high. I tried adding another transistor in series with the first one (NPN switching PNP transistor) but that just created smoke
I'm confused as to how to give this setup a better "snap"...
I have attached a picture of the circuit diagram and hope you can help me. Thank you so much!
-Andy
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