Review: RDQ Smoke Stopper (Solid State Smoke Inhibitor with LED & PPTC)

by Oscar

Too lazy to build a smoke stopper? RaceDayQuads and BengineeringLabs have you covered with their “plug and play” solid state smoke inhibitor. It gives you peace of mind when testing new mini quad builds and minimizes the chance of hardware damage due to electrical shorts.

Some of the links on this page are affiliate links. I receive a commission (at no extra cost to you) if you make a purchase after clicking on one of these affiliate links. This helps support the free content for the community on this website. Please read our Affiliate Link Policy for more information.

They offer two versions of different connectors, though the specs look to be identical.

I explained what a smoke stopper is In this tutorial, and how you can build your own from scratch.

How does it work?

The RDQ smoke stopper is basically a PPTC resettable fuse with an LED indicator. Simply use this device in between your battery and mini quad, it’s supposed to stop large current surge from hitting your electronics on the quadcopter.

The PPTC fuse trips when the current reaches 2.2A for longer than 0.5s. The fuse is then reset automatically once it’s cooled down (unplug for 10 seconds).

Contrary to the bulb version smoke stopper, the LED on the PPTC version turns on when it’s okay, and it turns off when there is a short (or too much current passing through).

A Handy Tool !

I haven’t extensively tested this tool. But RaceDayQuads told me that they haven’t received any reports of their smoke stopper failing the purpose. They added, “the only place it would fail is if someone wires a 16V power source to a 5V system, nothing will save that.”

Unlike the DIY light bulb smoke stopper which is rated for 3S LiPo, the RDQ one supports up to 24V (5S). I actually tested it on 6S briefly and it seemed to work just fine. But it’s probably safer to use an empty 6S pack that has a voltage below 24V.

The cost is about the same as building your own using a light bulb, and you don’t have to go through all the trouble with DIY.

And it’s so much more compact and portable! See the size comparison.

Controversy

The original creator of Smoke Stopper doesn’t seem to be very happy with this product because of the use of the name. He also pointed out the imperfection with PPTC:

It (Solid-State Smoke Stopper Inhibitor from RDQ) allows excessive current to flow for far too long before tripping… It permits much higher inrush current than the bulb and for much longer… Furthermore, this action of the PPTC pretty much eliminates one of the best features of the SmokeStopper™ (bulb version): use as a diagnostic tool for locating the source of the short if it DOES light up.

You can find out more about his claim here: https://www.rcgroups.com/forums/showpost.php?p=39132360

If you have the RDQ Smoke Stopper, what’s your experience? Let me know in the comment below.

Giveaway

I am giving these away to my Patreon supporters: https://www.patreon.com/oscarliang.

Leave a Comment

By using this form, you agree with the storage and handling of your data by this website. Note that all comments are held for moderation before appearing.

8 comments

Harold 24th January 2025 - 4:25 am

You have some really good info on fpv drones ☺️☺️☺️☺️

Reply
Wim 19th July 2019 - 2:21 pm

Fried three engines, 4 In 1 esc and fc while using this smokestopper. I couldn’t see there was a short between the bottom of the ESC and the frame. The smokestopper had a green light. I plug in the battery and poof, 200 dollars gone. It is more likely a false feel of security. Use a multimeter!

Reply
Superdad3d 2nd June 2019 - 2:20 am

My babyhawk pro took an unfortunate dive into a bayou and after disassembling and drying it all out I powered it up with the RDQ smoke stopper attached to a 3S battery and *poof*, one of my esc’s in the 4-in-1 board went up in smoke. The green LED light stayed lit until I unplugged the battery. My fault for not diagnosing with a DMM first.

Reply
rodofpv 17th May 2018 - 4:39 pm

I use the smoke stopper mostly to protect me from the spinning props when configuring ESCs (or other stuff where I need the battery connected) rather than to save the electronics. For that I use regulated power supply where I can set the maximal current I want.

Reply
Val45k 17th May 2018 - 12:23 pm

I use smoke stopper from hobbykng with 2a fuse, the whole thing was very simple for me until this occured, as i undersand this correctly 2a fuse should burned out fast enough when amps go high, and the only variable is the hardware im using, rights?

Reply
FrankT 17th May 2018 - 5:10 am

Use a power supply where you can setup the current draw. I start with 300/500 mah if it draws more it will cutoff.

Reply
Mike 16th May 2018 - 3:40 pm

It’s not as reliable as it sounds.
I was testing a new 4in1 ESC that had the pinout mislabeled and my FC was fried. It’s entirely the ESC manufacturer’s fault, but I was hoping the smoke stopper could have saved my parts.
I also made some soldering errors on before that led to magic smoke even with the RDQ smoke stopper, so it’s not totally “smoke stopping”. No light bulb smoke stopper has ever failed me, not once.
So if you want a more reliable solution, you should definitely build your own using bulbs.

Reply
Luiz Eduardo 15th May 2018 - 12:07 pm

I have one and it does not work. My Bardwell F4 came with a shorted S2 motor signal pad that I failed to detect before testing with the RDQ smoke stopper and it fried the board and the light stayed one all the time.

Reply