the arduino is still drawing about 60 mA of
This article from Make Magazine shows how it is done:http://blog.makezine.com/archive/2009/02/connecting-a-relay-to-arduino.htmlIt's OK for the relay to draw 60 milliamps from the 5V supply. You just don't want to draw 60 milliamps from a digital output pin. The transistor draws a little current from the digital output pin to switch a larger current through the relay coil.The diode across the coil protects the transistor and Arduino from the high reverse voltage spike induced in the coil when the magnetic field collapses.
According to the arduino uno page, there is 40 mA at each digital output pin.
Please enter a valid email to subscribe
We need to confirm your email address.
To complete the subscription, please click the link in the
email we just sent you.
Thank you for subscribing!
via Egeo 16