I dont know if I am about to embarc on the arduino-trip or not so I place my question to the allmighty community!
I have 3 pushbuttons thats should operate 3 relays. Every push of a button should activate or deactivate its dedicated relay.
But I also want a timer to start when the relay is activated, after ~60 seconds the relay should be deactivated
Is this doable with arduino and can you guys hint me in the right direction about hardware and program examples?.
I got a UNO r3 from a friend, is that enought or do I need some other hardware? (relays, buttons, etc of course!!)
You need relays In general you can not directly control relays from the Arduino but you need some form of driver. You can buy readily assembled boards (e.g. with 4 relays that have everything that is needed) that you can basically straight away hook up. Just pay attention to power supply.
From a software perspective, it should be reasonably easy.
Check if button pressed
if so, if relay is on, switch off
else switch relay on and 'record' current time
Check time
if 60 seconds passed, switch relay off.
Thanks.. I will then dig into this world (Stolle 0 experience of arduino)
I thought that I would be able to feed the relay-coil directly from an output on the uno r3
You can run tiny "reed" relays directly from pins IF the coil current is less than 20mA but you still need a kickback diode across the coil and be very careful with diode polarity.
In general you can not directly control relays from the Arduino but you need some form of driver. You can buy readily assembled boards (e.g. with 4 relays that have everything that is needed) that you can basically straight away hook up. Just pay attention to power supply.