- Joined Nov 26, 2021
Hello friends I really need your help as an expert on this forum. I have 2 twelve volt relay, which I connected them in parallel and after that I created a voltage regulator using tip122 transistor as a voltage supply which I adjust the voltage to 12v to supply the relay coil with a 12v and also used the reed switch as a switch to activate the relay coil when the reed switch in contact with magnets. Everything works fine, but later and found out that the tip122 is getting very hot so I tried finding out why it's getting hot and I found that when the relay coils are activated that's when tip122 start to get hot but when it doesn't activate it doesn't get hot. So after all the above said tip122 is getting very hot so I decided to use the big heat sink and the tip122 stopped getting hot but it's rather the heat sink that get hot when it stay for some minutes. Please I need your solutions and I want to ask if it's OK to leave the heat sink get hot. Your help will be highly appreciated.