ADWSystems
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I am using an Arduino Uno to drive a single input on a ULN2803 connected to a 12VDC relay. The power for the relay and Arduino are from separate 5V and 12V outputs of the same power supply. The 12VDC relays is used to control a 24VDC pump (power supplied from a separate supply). After a few toggles of the output/relay/pump the Arduino freezes/becomes unresponsive.
I have used ULN2003 and ULN2803 for years. The ULN2803 pin 1 is attached to the Arduino output, pin 10 is connected to 12VDC, Pin 18 connected to the relay coil (the other relay pin also connected to 12VDC). Pin 9 is connected to the arduino ground and also the 12VDC ground, which ends up being the same ground on the 5V/12V power supply. Additionally, I have installed a snubber diode across the 24VDC pump (just in case).
I'm trying to figure out what is causing the Arduino to lock-up. Any thoughts?
I have used ULN2003 and ULN2803 for years. The ULN2803 pin 1 is attached to the Arduino output, pin 10 is connected to 12VDC, Pin 18 connected to the relay coil (the other relay pin also connected to 12VDC). Pin 9 is connected to the arduino ground and also the 12VDC ground, which ends up being the same ground on the 5V/12V power supply. Additionally, I have installed a snubber diode across the 24VDC pump (just in case).
I'm trying to figure out what is causing the Arduino to lock-up. Any thoughts?