1st post so please excuse any deviance from the usual format.
Very new to Arduino.
Project - Temperature sensor for activating external fan on PC.
Aim of project - To automatically start an external fan when a temperature is reached ... useful while gaming.
Components used - DHT11 Arduino Uno clone 5v Relay 12v 1A power supply 12v to 5v converter(for DHT11 & relay)
Now, i see quiet a few posts about this issue, however most of these were code issues. My code has only 2 lines - If temp is 42deg - change o/p to high If temp is 40deg - change o/p to low
The high/low drives the relay which switches a fan on/off.
Everything works fine when the USB is connected. So no problem with the code(i believe/hope).
When i remove the USB ... the whole things seems to go into a 2-3 sec cycle. It will remain on & then switch off every 2-3 seconds. So definitely a power issue. Or thats what it seemed like. The whole thing is powered by a 1A power supply. So dont see what is wrong. I thought the fan was drawing more power so i disconnected the fan, but still the same thing. The relay will remain on for 2-3 or sometimes 4 seconds & shut down for about 1-2 seconds & then repeat the cycle. The whole time the board remains ON.
How much power does a board consume? How much power does a relay consume for remaining active?
Are there some known issue regarding the boards? II have tred a few solutions like connecting a resistance between the TX & RX ... Connecting a diode between the RESET & 5v etc.
Any other suggestions?