<p>A small scale power supply with over-current protection also works well. </p>

<p>The type to get are little cheap build yourself units, with a display that allows you to adjust output voltage and display output current.</p>

<p>They can be powered from a lipo.</p>

<p>They are useful for a whole bunch of things, but in the smoke stopper situation they go to max current and that's it.  The one I have is limited at about 3A which is similar in protection to a 36W 12V light globe.  Obviously, smaller light globes give more protection by blowing up.</p>

CC BY-SA 4.0
2020-04-29T01:33:39.693Z
2020-04-29T01:33:39.693Z
ctzsnooze
<p>There are two problems to mitigate here - incorrect polarity and overcurrent - which have different solutions but can be used together.</p>

<p>To protect against a battery being connected backwards you need to add a diode in series with the battery. This will cause a voltage drop - from 0.7V to 1.4V depending on the diode - and will need to be rated to handle the peak expected current.</p>

<p>To protect against overcurrent you will need a fuse, again rated to be above the maximum expected current. Fuses can come in quick blow or slow blow, depending on how quickly you want the fuse to react to overcurrent.</p>

CC BY-SA 4.0
2020-04-26T14:20:28.417Z
2020-04-26T15:16:57.120Z
2020-04-26T15:16:57.120Z
Kralc
<p>There are different ways, but a common one is to put a light bulb in series with the positive battery lead.</p>

<p>This works because it will allow low currents through to power the flight controller, but if there is a surge in current from a short the bulb will light up and sap away the energy.</p>

<p>You need to make sure you have a light bulb rated for the voltage you intend to put through it - for example if you have a 3V light bulb and use it as a 6S smoke stopper, the filament will melt.</p>

<p>This guide by Joshua Bardwell is great to build a switchable smile stopper: <a href="https://youtu.be/I5a0TAmEwLE" rel="noreferrer">https://youtu.be/I5a0TAmEwLE</a></p>

CC BY-SA 4.0
2020-04-26T13:54:44.087Z
2020-04-26T15:08:31.870Z
2020-04-26T15:08:31.870Z
Drones and Whatnot
<p>What is the right way to build and use a "smoke stopper" device to prevent a short or other improper wiring from damaging your electronics? </p>

<p>Is it different depending on what voltage you are using?</p>

<electronics><wiring><building>
How do you build and use a smoke stopper?
5zero7rc
# How do you build and use a smoke stopper?

(Asked by: username_0 on 2020-04-26)

What is the right way to build and use a "smoke stopper" device to prevent a short or other improper wiring from damaging your electronics?

Is it different depending on what voltage you are using?

**Tags:** electronics, wiring, building


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## 3 answers

### Answer by username_3 on 2020-04-26. Score: 7 | Accepted answer

There are different ways, but a common one is to put a light bulb in series with the positive battery lead.

This works because it will allow low currents through to power the flight controller, but if there is a surge in current from a short the bulb will light up and sap away the energy.

You need to make sure you have a light bulb rated for the voltage you intend to put through it - for example if you have a 3V light bulb and use it as a 6S smoke stopper, the filament will melt.

This guide by Joshua Bardwell is great to build a switchable smile stopper: <https://youtu.be/I5a0TAmEwLE>


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### Answer by username_1 on 2020-04-29. Score: 4

A small scale power supply with over-current protection also works well.

The type to get are little cheap build yourself units, with a display that allows you to adjust output voltage and display output current.

They can be powered from a lipo.

They are useful for a whole bunch of things, but in the smoke stopper situation they go to max current and that's it. The one I have is limited at about 3A which is similar in protection to a 36W 12V light globe. Obviously, smaller light globes give more protection by blowing up.


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### Answer by username_2 on 2020-04-26. Score: 4

There are two problems to mitigate here - incorrect polarity and overcurrent - which have different solutions but can be used together.

To protect against a battery being connected backwards you need to add a diode in series with the battery. This will cause a voltage drop - from 0.7V to 1.4V depending on the diode - and will need to be rated to handle the peak expected current.

To protect against overcurrent you will need a fuse, again rated to be above the maximum expected current. Fuses can come in quick blow or slow blow, depending on how quickly you want the fuse to react to overcurrent.


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