Does the relay control have a ground that goes from arduino to breadboard then to relay control? Just checking.
This is the LAST time I am asking you: what happens if you just switch the relays without solenoids connected to the relays.
Quote from: liudr on Oct 24, 2012, 05:54 amThis is the LAST time I am asking you: what happens if you just switch the relays without solenoids connected to the relays.I would like to give you a definitive answer, but I can't. It took entire day to reproduce this problem once (with the solenoid connected). A few days ago I did disconnect the solenoid, and the problem did not occur for the entire day. However, it does not mean the problem would not occur without the solenoid connected. Until I find a consistent way of producing the problem, there is just no way to be sure.
This may seem like a noob point, but I noticed your PCB doesn't have a ground flood? You should try adding one in to aid in heat-sinking!...apologies if you already know this
Hi dc42 and liudr,Thank you for your advice. Attached is a closeup of the Arduino with labels. It should clear up some confusion regarding the wiring.
Quote from: daytrader152 on Oct 23, 2012, 07:06 pmHi dc42 and liudr,Thank you for your advice. Attached is a closeup of the Arduino with labels. It should clear up some confusion regarding the wiring. You haven't yet implemented the suggestion in my reply #59 because the power and ground wires to the LCD do not follow the same route as the signal wires.Keep the +5v and ground wires to the relay separate from the ones to the LCD as far as possible. You shouldn't need to use the same ground pin for both because you have 3 ground pins on the mega. If the LCD and relay share the +5V connection, keep that shared wire as short as possible.How are you driving the relay: through a transistor?
@nanohex, would you mind clarifying the ground flood for me? I am not too familiar with it. Thanks./
Quote@nanohex, would you mind clarifying the ground flood for me? I am not too familiar with it. Thanks./I couldn't come up with a decent explanation in my own words so this is from Wikipedia:"A ground plane on a printed circuit board (PCB) is a large area or layer of copper foil connected to the circuit's ground point, usually one terminal of the power supply. It serves as the return path for current from many different components.A ground plane is often made as large as possible, covering most of the area of the PCB which is not occupied by circuit traces. In multilayer PCBs, it is often a separate layer covering the entire board. This serves to make circuit design easier, allowing the designer to ground any component without having to run additional traces; component wire needing grounding is routed directly through a hole in the board to the ground plane on another layer. The large area of copper also conducts the large return currents from many components without significant voltage drops, ensuring that the ground connection of all the components are at the same reference potential."Basically any area that's just left empty (copper etched away; no traces) is instead left with its original copper. These are then connected to ground.