Hello. I am a teacher at the end of an indoor automated garden project. I am getting frustrated with my relays working correctly.
2 relays one for light and one for pumping water.
The system just kind of clicks on and off on both relays.
Lets say a very simple program to turn on lights for 2 minutes then off and pump on for 2 minutes and off.
The relay has 3 pins. One for 5 volts (VCC) one for ground and one for input.
If I run the program it just switches one and off weirdly.
If I unplug either one relay the other works fine.
I keep trying different things, separate power supply for the relay. Have one relay hooked to the 3.7 volt pin. nothing fixes the problem.
Now I see the project I built as a demonstration for a hydroponic set up has 2 relays plug to the arduino and it has been great for 2 months working fine? The relays are of an older type?
Any thoughts? all arduinos are the UNO kind.
Thanks for any help. I want to put the projects in eth art show next week so I am running out of time.