I have killed my Arduino Uno already

I am brand new to the whole Arduino thing. I am using it to run a Nema stepper motor that winds up the weights to a clock that i have made. See it running here https://www.youtube.com/watch?v=_-5UwqylNQ4

Initially i was using an old 4A 12V power supply that a mate gave me. Upon testing the power supply was unable to supply the 6A that was required. No surprise here.

I went to jaycar and purchased one of these https://www.jaycar.com.au/mean-well-150w-12v-12-5a-power-supply/p/MP3291.

I hooked up the new unit and it blew the arduino. The RX/TX chip was too hot to touch. HELP! Its the second unit that has been fried. I have checked th voltage at the arduino and it reads 11.7V or so. cheers Dean.

Nice clock. Looking at your circuit, the problem is …

Oh wait.

(there is no circuit shown)

No idea how it is wired without a diagram. You could be spiking voltage in many areas. The power supply you have shown is what is commonly used in arcade games.

Even with its 'protection' circuits (which mainly means for input surges), any circuit attached to it should still be regulated and isolated via transistor/caps for protection.

Hi
I noted you are still using the DuPont wiring in a hanging installation, I think you need to got to a proper soldered assembly.

Use a prototyping board like this to plug into the UNO and solder to the board.

Tom… :slight_smile:

proto.jpg

Hi, Have you got the current limit set on the stepper controller unit? If so to what value, the same as the supply or the motor?

Would you be able to change the chain ratio to produce more torque and less speed at the winch drum? Hence less drive current required.

Thanks.. Tom.. :)

Here is the only diagram i have used.

Have you got the current limit set on the stepper controller unit? Not sure. Where do you look?
If so to what value, the same as the supply or the motor?

Would you be able to change the chain ratio to produce more torque and less speed at the winch drum?
Hence less drive current required. I could but the ratio seems fine.

any circuit attached to it should still be regulated and isolated via transistor/caps for protection?> How is this done. ?

Still wondering why the uno is receiving too much voltage when the measured out put is 12V
Thanks for all the advice.

Dean.

1964deano: Here is the only diagram i have used.

Have you got the current limit set on the stepper controller unit? Not sure. Where do you look? If so to what value, the same as the supply or the motor?

Would you be able to change the chain ratio to produce more torque and less speed at the winch drum? Hence less drive current required. I could but the ratio seems fine.

any circuit attached to it should still be regulated and isolated via transistor/caps for protection?> How is this done. ?

Still wondering why the uno is receiving too much voltage when the measured out put is 12V Thanks for all the advice.

Dean.

1964deano: I have checked th voltage at the arduino and it reads 11.7V or so.

Unless this is connected to the RAW aka Vin pin (or the reset which I think can also specifically handle 12V) that's pretty deadly for an Arduino of just about any kind.

the 12V is soldered to the 12V connector. That should be ok shouldnt it? Dean.

Should be.
Now how about the rest of your circuit? Without that we can’t offer much if any help.

1964deano: I hooked up the new unit and it blew the arduino.

'hooked up the unit' doesn't provide much at all in terms of details about the connections that you made between the power supply and the arduino. The first step is to just power the arduino without anything else connected to the arduino. So it will be necessary to show how you connected the power supply to the arduino..... eg. the pins that were used.

That schematic is helpful.

Is is likely that you have overloaded the Arduino voltage regulator. Does the Uno work if you unplug everything and power the Arduino with USB?

While the spec sheet says 12V input is okay, it doesn't say that the output current has a limit and that limit is smaller at higher voltage. Can you estimate or measure the total current required at 5V in your circuit?

The solution is to get a 5v power converter such as a cellphone charger to power the 5v side of your project.

MorganS: That schematic is helpful. Thanks.

Is is likely that you have overloaded the Arduino voltage regulator. I agree. It is almost too hot to touch. Does the Uno work if you unplug everything and power the Arduino with USB? No it will not connect to the laptop in any way.

While the spec sheet says 12V input is okay, it doesn't say that the output current has a limit and that limit is smaller at higher voltage. Can you estimate or measure the total current required at 5V in your circuit? Not much. The 5V part of the circuit only runs the hall sensors i think.

The solution is to get a 5v power converter such as a cellphone charger to power the 5v side of your project.

I agree. I was thinking of running the Uno from the 6V supply the runs the coils. Will that work? Can i reduce to 5V somehow? This did originally work before the storm on Saturday here in sydney.

thanks

Dean.

Dean.

I see a couple problems with your circuit, especially in the power connectors:

First, it looks like you have the negative 12 volts on the inner pin of the barrel jack connector, and positive on the outside. That is backwards.

Second, you seem to be powering the Arduino from both the 12 volt supply, AND from the 5 volt input using an external regulator. This will cause problems. Choose one, ditch the other.

The module on the right is a relay. It is using 5V power provided by the Arduino.

The module on the right is a relay. It is using 5V power provided by the Arduino.

And that of course is a problem in itself, that relay almost certainly draws much more than the Arduino can supply (even more so as it's powered at 12V so its puny regulator will overheat very quickly).

I have connected the 12V+ to the inner pin not the other way around. I have also run the 12V through a voltage regulator and reduced to 10V. I have a switch that turns off 10V when i connect the usb cable for programming. seems to work.

Dean.

pic of electronics

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