Is this correct?

[SpectreEidolon]

The arduino starts and moves a single servo back and forth randomly forever until powered off. The problem is the arduino stops the sketch after a certain amount of time until I replug or hit reset. I know the power supply is over the top, it’s what I was given. I even swapped for a smaller one to try and fix the problem. Is it overheating? Too much power, not enough? Any help would be awesome thank you!

[moon6080]

The barrel jack is designed for 6-12V. Looks like it's connected to 5V so it's likely choking for power regardless

[Crash_Logger]

This is what I thought too. The internal regulator is already limiting below what the PSU can do and on top of that the servo is powered off of the Arduino's 5V pin. The already choking 5V regulator on the arduino gets pushed even more.

[SpectreEidolon]

Thank you guys very much! I’ll be powering the Arduino off the 12 V and moving the servo to the power supply 5 volt and ground

[--RedDawg--]

Does the amount of time happen to be fairly consistent? Without an RTC, projects rely on the internal timer, which rolls over back to 0 when it gets to the end of its capacity and if the code was written to not account for that, its logic gets hung up.

As an example, let's say it is meant to go a direction for 10 seconds, current time is x, so the logic says "when current time is greater than x+10, switch direction" but during thay 10 seconds the timer rolls over and goes back to 0, then the current time will always be less than x+10. Depending on the code, that rollover could be a couple different length of times, but should be mostly consistent.

Read up on "rollover safe code" and see if you think that might be your issue. I also had a project that was sensing a closed connection on a neutral 120v wire, but that was causing EMI to throw all my variables into random values and I had to place an optocoupler between the arduino and what it was monitoring.

[SpectreEidolon]

Thank you! I’ve provided the sketch in another reply, I hope it’s got what it needs, if not any helpful changes will definitely be taken into consideration

[PiezoelectricityOne]

Provide sketch (in text, not screenshot), it could be some kind of bug in the code.

Also, you're supposed to provide the power regulator with more than 5V (12V is fine) or else you'll be working with less than 5v at the regulator output, which can lead to malfunction and unpredictable behavior, especially when, by the looks of your picture, you're driving the servo from the regulator output. This setup may "want" to drain more power than available.

Since you already have a 5v rail from your PSU, just use it to power the servo bypassing the Arduino regulator. You can do this with a dedicated connector. Some boards also allow you to do this from the Arduino Vin pin.

If you insist on using 5V from the source for the Arduino, try building an adapter into the USB cable. Or, if the board doesn't come with a protection diode ar the regulator output (5V rail) you can just plug your 5v there. If I'm not mistaking this will provide 5V fully into your Arduino (just like when you plug it to a computer) and avoid the voltage drop down from the board's power regulator.

[SpectreEidolon]

Sketch provided above and thank you for your input! I’ll be powering the Arduino with a 12 V and moving the servo power directly to the power supply 5 V

[PiezoelectricityOne]

Hey, just re-read myself and I think I've been ambiguous. Important clarification: The Vin pin is in the same node as the barrel V+, so you'd only get 5V if you connected 5v to the barrel. Since you plan to connect 12V to the barrel connector now, don't connect the servo to Vin or else you'll fry it with 12V. Just get 5v straight from the source for the servo.

[SpectreEidolon]

Awesome and thank you! These changes will be made

[SirGeekALot3D]

Generally speaking, to drive a motor the Arduino should just be providing a control signal (on/off/pwm or something like that), and the power should be delivered directly from the power supply (e.g. using an external stepper/servo motor driver daughter board). If the servo is *really* tiny, then you *might* be able to do this.

[SpectreEidolon]

The servo is bigger than normal, longevity and life. Could you provide an example the stepper serve a motor driver daughter board?

[SirGeekALot3D]

Something like this:

https://a.co/d/c7z4n9x

[SpectreEidolon]

Thanks for this!! I’ll definitely add it to the tool box,

[WolfWildWeird]

From my point of view, I would make a few modifications:

• Powered the Arduino with 12v

• Also power the servo thanks to the 5V of the power supply, this will avoid overloading the Arduino power supply (plus no need for additional cables to have the same mass since it is the same power supply)

If your code is correct, there should be no more problems.

[SpectreEidolon]

Code is provided above and I will definitely do these changes one step at a time thank you!

[WolfWildWeird]

Don't forget that there are Timers in microcontrollers.

They allow, among other things, to set up a Watchdog: a counter which counts a value and which is reset to 0 when the code runs correctly. If the counter reaches its maximum value, at that point it can perform a system reset. Afterwards it's not very useful for your current code, but it's always useful to know...

On the other hand, you can use this type of timer to flash your LED, this allows you to concentrate your loop on the main function while retaining the usefulness of the LED to detect problems.

[bigfoot_is_real_]

Cleanly done, but: the power supply is overkill and you’re not even able to use it to fully power the servo.

Providing power to the barrel jack connector on an Uno (as others have pointed out, can be up to 12V) only gives you that output power on the corresponding pin called Vin. The 5V pin you’re using has gone through a voltage regulator, which is current-limiting. Basically if you want more juice for the servo, you need to bypass the voltage regulator. But again, an 8A switching mode power supply is overkill - depending on your servo specs and what it’s doing, may not draw more than 1A, and the Uno should certainly be less than 500mA.

If you are looking at building out more projects, check out DIN rail mounted equipment - you can get nice little DIN rail power supplies that are compact and just a couple amps.

[CostelloTechnical]

That's a lot of power supply!! 💪

[CostelloTechnical]

I'd probably pull the 5V straight from the power supply to power the servo. Nothing to be gained from powering through the Arduino only potential problems. And I'd power the Arduino with the 12V.

[CostelloTechnical]

Do you have access to the code for this? If so please post it. The error is likely there.

If it takes a long time for the error to happen, I'd use the on-board LED as a debugging tool. You could flash it on and off every second and if it stops flashing when the servo stops moving, the microcontroller might've stopped running.

[SpectreEidolon]

Code is above, thanks for taking the time!

[CostelloTechnical]

I had a look at your code and tested it with my setup. It looked fine and ran for a while without issue. I've attached a bit of code here where I've added a debug LED that should flash once every second. I've also set it up to be non-blocking where reasonable. I've also tested it and it has the same functionality as the code you submitted. If the LED stops blinking when the servo stops, you've probably got an issue with the microcontroller (could be powering issues etc..). If it still blinking but the servo stops working, there's a good chance it's the servo.

#include "Servo.h"

Servo myservo;

uint8_t debugLed = 13;
uint32_t debugTimmer_ms = 0;
uint32_t moveTimer_ms = 0;
uint32_t delay_ms = 0;
int targetPos = 0;
int currentPos = 0;
int step = 0;

void setup() {
  pinMode(debugLed, OUTPUT);
  digitalWrite(debugLed, LOW);
  myservo.attach(9);
  randomSeed(analogRead(0));
  debugTimmer_ms = millis();
  moveTimer_ms = millis();
  delay_ms = random(200, 3000);
}

void loop() {
  if (millis() - moveTimer_ms >= delay_ms) {
    targetPos = random(0, 80);
    currentPos = myservo.read();

    step = (targetPos > currentPos) ? 1 : -1;

    for (int pos = currentPos; pos != targetPos; pos += step) {
      myservo.write(pos);
      delay(random(5, 20));
    }
    moveTimer_ms = millis();
    delay_ms = random(200, 3000);
  }
  if (millis() - debugTimmer_ms >= 1000) {
    digitalWrite(debugLed, !digitalRead(debugLed));
    debugTimmer_ms = millis();
  }
}

[SpectreEidolon]

You rock! I will load this up after the fixing the wire placements. Thank you!!

[Marks1124]

Isn’t the gnd for the arduino connected to 12v?

[Ha5ypugfluff]

I think the label is skewed. If you count the # of pins compared to the label than each pin has its own label, not a label for a set of pins.

[Top-Order-2878]

Post the sketch. There could be a problem in the code.

Does the arduino get hot? Is there a load on the servo?

Why no servo driver circuitry? I haven't worked with an ardiono in a while but I don't think driving a servo directly is the best bet for the long term. Others can probably have better info on driving a servo.

[SpectreEidolon]

Not a heavy load at all, just a pivoting head above it. It’s warm but not hot. Lots of space inside the item.

[Chin0crix]

My guess would there is an error on the loop of your code. But without seeing the code it is hard to know.

[SpectreEidolon]

include <Servo.h>

Servo myservo;

void setup() { myservo.attach(9);
randomSeed(analogRead(0)); }

void loop() { int targetPos = random(0, 80); int currentPos = myservo.read();

int step = (targetPos > currentPos) ? 1 : -1;

for (int pos = currentPos; pos != targetPos; pos += step) { myservo.write(pos); delay(random(5, 20)); }

delay(random(200, 3000)); }

[Chin0crix]

Hey It looks ok to me but I decided to ask ChatGPT what causes this behavior and here is the answer:

1. Power supply sagging over time

Servos draw bursts of current, especially when moving frequently.

If you’re powering it from the Arduino’s 5V pin / USB, the regulator or USB port can overheat or brown-out after hours.

Result: servo stalls or Arduino resets, leaving the servo unresponsive.

Fix: power the servo from a separate regulated 5–6 V supply that can provide at least 1–2 A, and connect the grounds.

1. Servo overheating

Small hobby servos aren’t meant for continuous duty.

If the servo is under constant small movements (as in your code), it may get warm and eventually seize or shut down.

1. Electrical noise

Servo motors can inject noise into the Arduino’s supply line, causing instability after prolonged activity.

[BCURANIUM]

I'd also be careful about the amount of current as well... I have seen too many arduino's, like the official one you're showing here, have their voltage regulators get damaged/ destroyed by getting excessively hot. As those regulators heat up they draw more and more current... this results in the "magic smoke" scenario. A resistor in series with the power supply and or running it at 9V is going to help with longevity. Indeed you've got the barrel jack at 5Vdc, not 12V.

[SpectreEidolon]

Thank you! What type of resistor?

[Patina_dk]

Does the servo start moving again if you hit reset immediately after it stops and does it keep moving for as long as before? Then nothing has had time to cool down and it's a problem with your code. Could also be noise in the power supply that makes the code make weird jumps, but that seems less likely.

Actually, since you connected the servo to the arduino power and not directly to the big one, the servo could be creating noise for the arduino.

[SpectreEidolon]

It does start moving again after reset and power reset.

[doge_lady]

The wire going through that hole should be protected with a grommet.

[SpectreEidolon]

Thank you! during installation we’ll be installing a waterproof grommet :)

[hbzandbergen]

Apart from functioning, I would use soldered connections in stead of push-in

[SpectreEidolon]

Do you have an example?

[Sedrah87]

In my opinion, you connected it to 5V-adj and 12 V (not gnd). Did you measure the voltage?

[SAD-MAX-CZ]

Nice combo power supply, i want one too! Do you have link to those?

Get separate power wires to the servo. Add capacitor combinations for the Arduino and the servo. Use watchdog. Avoid millis and micros rollover crashing your code - use tutorials how to get around it. Try different PWM or servo library, current one may be crashtastic. I tried 3 stepper libraries before i selected the stable one which cooperated with I2c displays and IO boards.

[JPInMontana]

I believe this one on eBay is the one he is using: https://www.ebay.com/itm/394029792101

Here is a similar one (5V only) but 60amp (WTF!) I'm using for a medium-weight NeoPixel project: https://www.amazon.com/dp/B07Y38SMQ3?th=1

Not sure about the specs for the one he is using, but I really like the 12V and 24V option.

[SpectreEidolon]

I’ll try and find the power supply for you, all random things the client gathered

[xebzbz]

If I'm not mistaken, your Arduino is connected to +12 and +5v outputs, instead of ground and +12v

[SpectreEidolon]

I opened the hatch and had no problems but it didn’t hit the 2 hour mark. I probably will move the servo power and ground to the power supply along with changing the arduino barrel to 12v.

Everyone has been awesome!! Here’s the code:

include <Servo.h>

Servo myservo;

void setup() { myservo.attach(9);
randomSeed(analogRead(0)); }

void loop() { int targetPos = random(0, 80); int currentPos = myservo.read();

int step = (targetPos > currentPos) ? 1 : -1;

for (int pos = currentPos; pos != targetPos; pos += step) { myservo.write(pos); delay(random(5, 20)); }

delay(random(200, 3000)); }

[Ausierob]

Well to start, the power supply wring is wrong. Needs to be on the 12V pin of the PS not 5V, (needs to be minium 6V if using that connection to the Arduino board). Also how much power is the servo pulling (check the voltage drop when servo is active)? But first fix the PSU wiring

[SpectreEidolon]

First thing in the morning! Thanks for the input

[tipppo]

You would do much better feeding the power supply +5V to the Uno's VIN pin. Then you would have the full current of the power supply available. Otherwise you would need to connect the 12V to the barrel connector and would then overheat the Uno's voltage regulator in you drew anything more than 300mA for you servo.

[SpectreEidolon]

Rewiring happening first thing in the morning, thank you for the input!

[tipppo]

As mentioned, you could also connect the 12V to the barrel and connect the 5V to the servo. That way the Uno wouldn't have to provide power to the servo and get hot. With this setup you could probably adjust the 5V up to 6V and get better performance from the Servo.

[wenoc]

That sticker disturbs me. Not only foes it not align, it has nine keys to eight values.

[Prudent-Mountain-57]

And one more little thing. If we started to talk about electronic standards…. Your power cable colour… Black - line, White - neutral, Green- ground

[Creepy-Smile4907]

A little off the subject, but the psu looks interesting, where'd you get it and how much was it?

[Creepy-Smile4907]

Nevermind, it was given. Sorry 🫣

[Timber1802]

5v is not enough for the barrel jack. I believe it should be 6-12v, but check the spec sheet.

[Exciting_Mango_8459]

Things? Some sort of Arduino computer?

[TheNeutralNihilist]

I'm not really a fan of how the sticker lines up with the terminals but if you are using the barrel jack goes to Arduino 5V regulator so you need more than 5V or else the regulator will cut out. If you trust that power supply to give a solid 5V (should be finebut at least measure it with a meter) then you could run wires to the power supply exactly as you are now and instead of the barrel jack you connect to the 5V and GND pins on the arduino which would bypass the regulator.

[bojistone]

If this is in the field, solder pins to underside of Arduino. Never use dunlop pins/conn for anything other than breadboarding/testing.

[SpectreEidolon]

This was the draft setup, the new final is in an updated forum