Go Down

Topic: 4.5-28V to 0.8-20V DC Step Down Buck Converter blew out after powering w/ 24V (Read 976 times) previous topic - next topic

knightridar

Hi, this

DC-DC 4.5-28V to 0.8-20V Output 3A MP1584EN Step Down Buck Converter

blew out on me after I supplied it with power from a 24V, 5A power supply.
I measured actual voltage to be approx. 24.6 V.
Although this converter can handle up to 28V.

https://bit.ly/32XAMIt

This is the power supply I am powering it with:
https://amzn.to/2ZgkhsL
24V, 5A, 120W.

My understanding is that current is drawn. So the buck converter can't draw more than 3A correct?
Why would it blow out?
I didn't even get a chance to adjust output voltage on the potentiometer.
I will try to hook up to an adjustable regulated voltage power supply to test out again.

In the picture below basically I was trying to step down 24 V of power to 3.3 V to power my Arduino Pro Mini. One thing that was different is that I did not have the Arduino Pro Mini plugged into the breadboard when the buck converter blew out.






Useful CAD/ 3D model files for
Arduino, hobbyist, and engineering projects

https://grabcad.com/has-2

wolframore

There's nothing that limits the current for any of your devices. The 3A 3.3v converter doesn't even have a fuse. What are you powering? It looks like a relay and perhaps a motor driver.  Those little 3A converters from what I recall shouldn't be pushed that hard. Try a fuse inline with it.
Bad Boys Race Our Young Girls But Violet Generally Wins - Get Some Now :) - ELI ICE man

TomGeorge

Hi, this

DC-DC 4.5-28V to 0.8-20V Output 3A MP1584EN Step Down Buck Converter

blew out on me after I supplied it with power from a 24V, 5A power supply.
I measured actual voltage to be approx. 24.6 V.
Although this converter can handle up to 28V.


Explain "blew out"?
What components "blew out"?
Can you post a picture of the "blown out" converter please?
Thanks.. Tom.... :)
Everything runs on smoke, let the smoke out, it stops running....

knightridar

@TomGeorge

It's the green pcb board below in the first picture in the first post below.
The black IC chip MP1584EN blew out.

If you click on the web link in the first post below it'll take you straight to the part and with more detailed pictures.

@wolframore

I'm powering a nema 17 stepper motor with the l298 h bridge.
It will be supplied with power from the 24V terminal blocks.
That l298 driver is capable of powering that for sure.

The 3.3V converter will power the 3.3V arduino pro mini and solid state relay.
These definitely would not exceed 3A of draw.
I'm estimating the 3.3V arduino pro mini will use ~200 mA.
The SSD relay (TWTADE SSR-40DD) maybe 40-50 mA when activated?

So is a fuse really necessary?
Useful CAD/ 3D model files for
Arduino, hobbyist, and engineering projects

https://grabcad.com/has-2

jremington

Quote
That l298 driver is capable of powering that for sure.
Probably not. Post a link to the stepper data sheet or product page.

The ancient, inefficient L298 driver cannot be used with the majority of modern, low impedance stepper motors.

knightridar

Here is the kysan stepper motor I am planning on using all it will do is half a rotation to spin a part.

Kysan nema 17 stepper 1124090
Data sheet says (4.2V, current per phase 1.5A)

L298
drok l298 dc h-bridge


The step down converter was not connected to the h-bridge and it won't be at all.
The SSD relay was not connected to it either.

I reattached the picture to simulate the exact scenario when it blew out.
 1. No relay or Arduino Pro mini were attached.
 2. The 24 Volt, 5A power supply was connected to terminal blocks
 3. The step down converter was connected to the terminal blocks and output was connected to
     breadboard

Note: I connected a spare version of the part to my regulated dc power supply (the output was set to around 11.5 VDC, I've changed it to 3.3V with a screw driver to turn potentiometer on it). The output was measured with a multimeter.





I'll try to get these inline fuses and put them right before the 3A rated step down converter. I'll try the 3A fuse first.

Inline automotive fuses with adapters, multiple amperages offered
Useful CAD/ 3D model files for
Arduino, hobbyist, and engineering projects

https://grabcad.com/has-2

jremington

If you apply 24 V to that 2.8 Ohm motor, each winding will draw 8.6 Amperes, until the smoke starts pouring out.

Unless you collect antiques, throw the L298 driver in the waste bin. Pololu has a good selection of modern, current limiting stepper motor drivers. Be sure to follow the instructions to set the current limit correctly.

knightridar

Yikes.... I was under the impression that voltage would automatically be stepped down or regulated like in the 3d printing hobby world by the l298 h-bridge.

For example I've seen a lot of 3d printers using 24 volt power supplies to connect to their control boards and then the stepper drivers mentioned below are used and placed into 2.54 mm dupont female pin connectors.

i.e. with drivers below would it work with a 24 Volt power supply connected to them?:
DRV8825, TMC2100, TMC2130,TMC2208, TMC2660

My understanding is that these stepper drivers will accept a range of voltage and then power the steppers accordingly based on their amperage capacity.
Is the board automatically taking care of the voltage or is it the drivers themselves that are adjusting it as it's sent to the stepper motor?

I found these below from pololu:
https://www.pololu.com/category/120/stepper-motor-drivers

What about these links using the l298 as a stepper driver? I get what you meant by resistance in windings. So it seems they either are using a lower voltage power supply or other type of compatible stepper.

https://tronixlabs.com.au/news/tutorial-l298n-dual-motor-controller-module-2a-and-arduino/

https://lastminuteengineers.com/stepper-motor-l298n-arduino-tutorial/
Useful CAD/ 3D model files for
Arduino, hobbyist, and engineering projects

https://grabcad.com/has-2

jremington

Quote
What about these links using the l298 as a stepper driver?
Both are typical, superficial, misleading tutorials by people who have no real understanding of what they are doing.

To use the motor you have at its maximum torque, you need a current limiting stepper driver than can easily handle 1.5 Amperes/phase, without extra cooling. Thie inexpensive TB67S249FTG from Pololu will do, or use an industrial stepper driver.

If you can get by with less than full torque, use lower motor current and a cheaper and less capable motor driver like the black edition A4988 (about 1.2 Ampere/phase without extra cooling).

Be sure to carefully follow Pololu's instructions on how to set the current limit. Those instructions are valid ONLY for Pololu drivers; beware of many cheaper imitations.

knightridar

So I basically supplied the circuit with 24V and am getting 3.3V output from the spare step down converter.
This time the step down converter did not blow out.
My power supply is 24VDC with 5 amps output.

The difference is this time around I didn't have the leads plugged into the breadboard.
The board was just open in the air.

Would it make a difference if I plugged in the arduino mini into the board?

I don't understand if I created a short that may have caused it to blow out.
I didn't have the paths meeting each other. Vcc in and ground were in different lanes.

Useful CAD/ 3D model files for
Arduino, hobbyist, and engineering projects

https://grabcad.com/has-2

knightridar

The Arduino pro mini is powering on now. Weird.
I have no fuse in the circuit.

I've adjusted the voltage to ~3.45V.
Since the potentiometer is really sensitive to movement I'm inputting the power to the raw pin.

This time around the board was not plugged into breadboard and even after plugging it in the buck converter did not blow out.

Last time around though I did not measure my output voltage of the step down converter
and I didn't adjust the potentiometer.
Also I had not grounded the circuit on the panel.
This time around I grounded the circuit to an M3 Stainless Steel screw fastened onto a plastic panel.

So maybe these two factors may have had to do with the buck converter blowing out.
Useful CAD/ 3D model files for
Arduino, hobbyist, and engineering projects

https://grabcad.com/has-2

Qdeathstar

Why are you bonding the plastic? Maybe your converter was defective out the box
A creaking creeping shadow
stiff against the freezing fog
glares at a tickless watch.

Time has failed him -- all things shall pass.

wolframore

The fuse is there to fail instead of other more expensive things. If something wasn't wired correctly it's hard to tell without a schematic. Attaching ground to a plastic panel has no benefit. It's still really impossible to tell what you're actually doing. Nothing but power to the micro and far as I can tell no motor or driver.
Bad Boys Race Our Young Girls But Violet Generally Wins - Get Some Now :) - ELI ICE man

Go Up