I am new to arduino and it has been quite some time since i have done much microprocessor work. I want to use an uno to operate a dpdt relay to open and close a linear actuator. one pole obviously for inward and a current reversing pole for the opposite direction. i am guessing the uno can output voltage to operate the relay but i want it to be on a timer. how would i even start programming this? thank you for your time
i am guessing the uno can output voltage to operate the relay
Sorry wrong. You will need a transistor to drive most relays. An arduino can output 5V at about 30mA so not many relay coils will take that little.
For a start you can look at the delay function, but in the end you will use another technique.
Go through the simple examples in the arduino IDE.
Grumpy_Mike:
i am guessing the uno can output voltage to operate the relay
Sorry wrong. You will need a transistor to drive most relays. An arduino can output 5V at about 30mA so not many relay coils will take that little.
For a start you can look at the delay function, but in the end you will use another technique.
Go through the simple examples in the arduino IDE.
A basic transistor setup would be pretty easy from the digital output of the arduino, how would i program the timer? i want it to be automatic and setup by time of day and day of the week.
The Arduino has no idea of day of week, so you'd want to add a real-time clock (RTC).
can't i use a time library and set programs for alarms? then program the alarm code for digital output and duration to transistor?
The functions within the time and alarm libraries will get the time from an RTC.
The RTC modules are inexpensive and will simplify many issues around the use of time in your program